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David Hill
Uppsats för avläggande av masterexamen i naturvetenskap30 hp
Institutionen för biologi och miljövetenskapGöteborgs universitet
June 2014
Environmental, Energy and Economical life cycle cost from Cradle to Cradle (3E cost-C2C method) evaluation of rock wool, polystyrene and cellulose fibre insulations
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Master Thesis Report: Environmental, Energy and Economical life cycle cost from Cradle to Cradle (3E cost-‐C2C method) evaluation of rock
wool, polystyrene and cellulose fibre insulations By David Hill Torpvägen 18 46694 Sollebrunn Phone: +46739267289 E-‐mail: [email protected] Date: 26 May 2015 Credits: 30 ECTS Study: Environmental Science, University of Gothenburg Supervisor, Chalmers Birgit Brunklaus Assistant Professor, Energy and Environment Phone: +46 31 772 86 13 E-‐mail: [email protected] Supervisor, COWI Lina Hammarstrand Master of Environmental Engineering Phone: 010-‐850 20 87 E-‐mail: [email protected]
Supervisor, COWI Johanna Millander Environmental Consultant Phone: 010-‐850 13 73 E-‐mail: [email protected] Course leader, University of Gothenburg Lennart Bornmalm University lecturer Phone: +46 (0)31 786 28 44 E-‐mail: [email protected]
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Abstract In 2013 Silvestre et al. wrote an article presenting a new method to evaluate building materials and/or wall constellations that affect the thermal performance of a building. The method takes the environmental, economical and energy (3E) performance into account throughout the life cycle, from cradle to cradle (C2C). The 3E’s are converted to costs so different wall constellations can be compared, even if they are not functionally equivalent. The 3E cost-‐C2C method has been evaluated with regards to relevance, ease of use and usefulness for the housing industry, consultants and entrepreneurs. To study this the 3E cost-‐C2C method has been used to assess three of the most common insulations used in Sweden: rock wool, expanded polystyrene (EPS) and cellulose fibre. They are examined primarily as if used in a passive house but also compared to a new built regular minimum standard house and an average existing house in Sweden. Cellulose fibre was the best option according to the 3E cost-‐C2C method with a total cost of 49 €/m2 of wall insulation with passive house thickness over a 50 year life span. The corresponding cost for rock wool and EPS were 80 €/m2. For a new built regular house that just meets the minimum standards the total costs over 50 years are 88 €/m2 for rock wool and EPS and 80 €/m2 for cellulose fibre. This can be compared to the energy cost for an average existing house in Sweden, which over 50 years is 193 €/m2 of external wall. The 3E cost-‐C2C method gave good, clear results with regards to the 3E’s and was a logical tool to work with. It follows the relevant standards and covers all steps of the examined products life cycle. The method is broad and encompasses all types of walls; different wall types and insulation thicknesses can be compared.
Key words: 3E cost-‐C2C method, thermal performance of buildings, environment, eco-‐cost, energy, economics, LCC, cradle to cradle, insulation, rock wool, expanded polystyrene, cellulose fibre
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Sammanfattning 2013 skrev Silvestre et al. en artikel som presenterade en ny metod för att utvärdera byggnadsmaterial och/eller väggkonstellationer som påverkar den termiska prestandan av en byggnad. Metoden tar hänsyn till miljö (environment), ekonomi och energianvändning (3E) under hela livscykeln, från vagga (cradle) till vagga (C2C). De 3Ena omvandlas till kostnader så olika väggkonstellationer kan jämföras, även om de inte är funktionellt likvärdiga. Metoden, som kallas 3E cost-‐C2C metoden, har utvärderats med avseende på relevans, användarvänlighet och användbarhet för byggnadsindustrin, konsulter och entreprenörer. För att kunna utvärderas har metoden använts för att bedöma tre av de vanligaste isoleringar som brukas i Sverige: stenull, expanderad polystyren (EPS/cellplast) och cellulosafiber. De har i första hand undersökts som om de använts i ett passivhus men har också jämförts med som de skulle ha använts i ett nybyggt vanligt minimistandard hus och ett genomsnittlig befintligt hus i Sverige. Cellulosafiber var det bästa alternativet enligt 3E cost-‐C2C metoden, med en total kostnad på 453 kr/m2 väggisolering med passivhus tjocklek över 50 års livslängd. Motsvarande kostnad för stenull och EPS var ca 739 kr/m2. För ett nybyggt vanligt hus som endast uppfyller minimistandarden från Boverket är de totala kostnaderna över 50 år ca 815 kr/m2 för stenull och EPS och 745 kr/m2 för cellulosafiber. Detta kan jämföras med energikostnaden för ett genomsnittligt befintligt hus i Sverige, som under 50 år är 1784 kr/m2 yttervägg. 3E cost-‐C2C metoden gav goda, tydliga resultat med avseende på de 3Ena och var ett logiskt verktyg att arbeta med. Metoden följer relevanta standarder och omfattar alla steg i de undersökta produkternas livscykel. Metoden är mycket allmän och kan appliceras på alla typer av väggar där olika typer av väggar och isoleringstjocklekar kan jämföras.
Nyckelord: 3E cost-‐C2C metoden, byggnaders termiska prestanda, miljö, eco-‐cost, energi, ekonomi, LCC, vagga till vagga, isolering, stenull, expanderad polystyren, cellulosa fiber
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Preface This thesis could not have been written without the help and knowledge of the following people, so thanks to:
Lina Hammarstrand, Master of Environmental Engineering and supervisor at COWI
Johanna Millander, Environmental Consultant and supervisor at COWI
Birgit Brunklaus, Research assistant in life cycle analysis and supervisor from Chalmers
Lennart Bornmalm, Lecturer at the University of Gothenburg and master thesis course leader
Yvonne Andersson-‐Sköld, Research and Development Manager at COWI
José Dinis Silvestre, Assistant Professor at the University of Lisbon, Architecture and Georesources Department
Joost G. Vogtländer, Associate Professor at the Delft University of Technology
Anders Linde, Architect SAR/MSA and certified Passive House Designer at Passivhuscentrum i Västra Götaland
Mikael Olofsson, Technical Adviser at Paroc AB
Emma Hansson, Environmental Manager at Paroc AB
Emil Syrèn, Product & Marketing Manager at Sundolitt
Andreas Östlund, VD/CEO at Miljöbyggsystem MBS AB
Also a special thanks to COWI and everyone at the MRS department, who let me write my thesis in their beautiful building and shared many lunches and coffee breaks with me.
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List of abbreviations C2C – Cradle to Cradle
EIAM – Environmental Impact Assessment Method
EPD – Environmental Product Declarations
EPS – Expanded Polystyrene
EUMEPS – The European Association of EPS
EVR – Eco-‐costs / Value Ratio
LCA – Life Cycle Assessment
LCC – Life Cycle Costing (another name for WLC)
LCIA – Life Cycle Impact Assessment
NPV – Net Present Value
VAT – Value Added Tax
WLC – Whole Life Costing
3E – Environment, Energy and Economic
GWP – Global Warming Potential
ODP – Ozone Depletion Potential of the stratospheric ozone layer
POCP – Formation potential of tropospheric photochemical oxidants
AP – Acidification Potential of land and water
EP – Eutrophication Potential
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Table of Contents
Abstract ............................................................................................................................. 2
Sammanfattning ................................................................................................................ 3
Preface............................................................................................................................... 4
List of abbreviations........................................................................................................... 5
1 Introduction ................................................................................................................. 8 1.1 Background ........................................................................................................................8 1.2 Aim and Goal......................................................................................................................8 1.3 Research questions ............................................................................................................9 1.4 Methods.............................................................................................................................9 1.5 Structure of report ...........................................................................................................10
2 3E cost-‐C2C methodology ........................................................................................... 11 2.1 Life cycle assessment (LCA)...............................................................................................11
2.1.1 Goal and scope .................................................................................................................12 2.1.2 Inventory analysis .............................................................................................................13 2.1.3 Life cycle impact assessment (LCIA)..................................................................................14 2.1.4 Interpretation -‐ weighting and single indicator ................................................................14
2.2 Eco-‐costs method .............................................................................................................15 2.2.1 Using EPD data..................................................................................................................16
2.3 Whole-‐life costing (WLC) method .....................................................................................17 2.4 Energy cost calculation .....................................................................................................17 2.5 Summing up with the Net Present Value (NPV) method ...................................................18
3 Thermal insulation materials...................................................................................... 20 3.1 Thermal conductivity........................................................................................................21
3.1.1 Insulating air .....................................................................................................................21 3.1.2 Density ..............................................................................................................................21
3.2 Fire class...........................................................................................................................22 3.3 Water vapour diffusion factor ..........................................................................................22 3.4 Rock wool ........................................................................................................................22
3.4.1 Thermal conductivity and density ....................................................................................23 3.4.2 Fire class ...........................................................................................................................23 3.4.3 Other aspects....................................................................................................................23
3.5 Expanded polystyrene ......................................................................................................24 3.5.1 Thermal conductivity and density ....................................................................................25 3.5.2 Fire class ...........................................................................................................................25 3.5.3 Other aspects....................................................................................................................25
3.6 Cellulose fibre ..................................................................................................................25 3.6.1 Thermal conductivity and density ....................................................................................26 3.6.2 Fire class ...........................................................................................................................26 3.6.3 Other aspects....................................................................................................................26
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4 Scope of the 3E cost-‐C2C analysis of insulations ......................................................... 27 4.1 Functional unit .................................................................................................................27 4.2 Lifecycle ...........................................................................................................................27 4.3 Time frame.......................................................................................................................28 4.4 Geographic boundaries ....................................................................................................28 4.5 Environmental impact categories .....................................................................................28 4.6 Example house .................................................................................................................28 4.7 Value Added Tax ..............................................................................................................29 4.8 Manufacturers .................................................................................................................29
5 Results of the insulation evaluation............................................................................ 30 5.1 Environmental impact cost ...............................................................................................30
5.1.1 EPD data ...........................................................................................................................30 5.1.2 Eco-‐costs method .............................................................................................................33
5.2 Economical cost................................................................................................................34 5.2.1 Acquisition cost.................................................................................................................34 5.2.2 Disposal cost .....................................................................................................................36 5.2.3 Total economical cost .......................................................................................................37
5.3 Energy cost.......................................................................................................................37 5.4 Summing up costs ............................................................................................................39
5.4.1 Regular new built minimum requirement standard house ..............................................40 5.4.2 Average existing house .....................................................................................................41
6 Results of method evaluation..................................................................................... 43 6.1 LCA...................................................................................................................................43 6.2 WLC..................................................................................................................................43 6.3 Energy cost calculation .....................................................................................................43 6.4 Project ‘Butterfly’ .............................................................................................................44 6.5 Variations of the 3E cost-‐C2C method...............................................................................44 6.6 3 E factor ..........................................................................................................................45
7 Discussion .................................................................................................................. 46
8 Conclusion.................................................................................................................. 47
9 Future development................................................................................................... 51
10 References ............................................................................................................... 52
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1 Introduction In this chapter an introduction of the thesis is presented. A background is given followed by an aim and goal. The research questions are stated, methods presented and an overview of the structure of the report offered.
1.1 Background
As passive houses become more energy efficient the environmental impact of the production and disposal of materials become a proportionally larger part of the total environmental impact of the building. One of the major materials used in passive houses is the insulation. It would be interesting to know which type of insulation on the Swedish market has the smallest environmental impact, although the environmental impact is not the only aspect to consider when choosing insulation. The housing industry also considers for example the economics and how efficient the insulation is. In an article by Silvestre et al. 2013 they propose a method to aid in comparisons of assemblies related to buildings thermal performance, with regard to the environmental, energy and economical (3E) life cycle from cradle to cradle (C2C) (Laszlo 2013, McDonough and Braungart 2002), following the new European Standards for the environmental and economic assessment of construction work. Life cycle assessment (LCA) gives the environmental performance and through prevention-‐based environmental impact assessment all impact categories can be converted to a cost unit. Heating and cooling gives the energy performance and the whole-‐life costing (WLC), also called life cycle costing (LCC), method give the economic performance (Gluch 2014). The 3E cost-‐C2C approach uses weights so that the 3E’s can be summarized in one unit, cost (Silvestre et al. 2013). Since the housing industry should be able to take all 3E aspects into account when choosing insulation, a summary of them seems to be an appealing option and the 3E cost-‐C2C method will therefore be evaluated. To evaluate the method three insulations used on the Swedish market were chosen to be analysed, so a secondary goal of the thesis is to determine which insulation performs best with regards to the 3Es.
The thesis is written in cooperation with COWI.
1.2 Aim and Goal
The aim of the thesis is to give the target groups (housing industry, consultants and entrepreneurs) further understanding of the 3E cost-‐C2C method and an evaluation of the method. A sub-‐aim is also to give the target groups an assessment of the environmental impacts and costs of some of the most commonly used insulations in passive houses, so they can make informed decisions when choosing insulation. For example, there are situations where different types of insulation are approximately as expensive in price for the same efficiency, so then the one with the smallest total environmental impact should be chosen. Currently knowledge of insulations environmental impact is not great within the target group, so the thesis aim is to clarify this.
The goal is to evaluate the 3E cost-‐C2C method to se if it is a useful method when comparing between assemblies related to buildings thermal performance. The goal is also to determine which insulation performs best with the 3E cost-‐C2C method.
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1.3 Research questions
The passive house market is growing and one of the major materials used in passive houses is the insulation.
A. Which one of rock wool, polystyrene and cellulose fibre insulation is the most suitable to use to reach the energy efficiency of a passive house, with regards to the environmental, energy and economical life cycle from cradle to cradle?
B. Is the 3E cost-‐C2C method a suitable method to compare building assemblies related to thermal performance?
To answer these two major research questions above the following questions need to be answered:
A1. What are the major environmental impacts of rock wool, polystyrene and cellulose insulation though out their life cycles from C2C? The environmental performance of the 3E cost-‐C2C method follows the LCA method.
A2. What is the cost of the environmental impacts of rock wool, polystyrene and cellulose insulation though out their life cycles from C2C? The 3E cost-‐C2C method uses the Eco-‐costs method to put weights on the environmental impact assessment method (EIAM) to convert the results from the LCA impact categories to an economic unit.
A3. What is the energy cost of rock wool, polystyrene and cellulose insulation during the use stage? The energy performance of the 3E cost-‐C2C method is calculated with a formula.
A4. What are the economical costs of rock wool, polystyrene and cellulose insulation though out their life cycles from C2C? The economic performance of the 3E cost-‐C2C method follows the WLC method using the net present value (NPV) method.
B1. Does the 3E cost-‐C2C method give a good indication of which insulation that performs best with regards to the environmental, energy and economical performance?
B2. Should the environmental impacts be summarized into one value for easier comparisons or can this be problematic?
B3. Are there other more suitable methods to compare building assemblies related to thermal performance?
1.4 Methods
The method for the master thesis will be the 3E cost-‐C2C method, which includes: a comparative accounting LCA that includes an Environmental Impact Assessment, the Eco-‐cost method, the Whole-‐Life Costing method and the Net Present Value method.
There is no method to evaluate a method, except to compare methods. So the 3E cost-‐C2C method will be compared to other methods with regards to applicability in comparing building components, how many areas of comparison they cover, usefulness for the designers needs and ease of use.
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1.5 Structure of report
The report is composed of nine parts.
The first chapter is an introduction and includes a background for the thesis, aim and goal, research questions and summarises the methods to be used.
The second chapter describes the 3E cost-‐C2C methodology, and the methods it is built upon. Benefits and limitations with the method will be examined, although a more comprehensive analyse will be made after the method has been applied on the insulations.
The third chapter describes the thermal insulation materials to be analysed, and why they were chosen. Their role and importance to sustainable construction is described. Pros and cons not covered in the 3E cost-‐C2C method are described.
In the fourth chapter the scope of the 3E cost-‐C2C analysis of the three insulations is defined.
In chapter five the 3E cost-‐C2C method is applied to the three insulations and the results of the evaluation are presented.
Chapter six gives a description of other methods with the same goal as the 3E cost-‐C2C method, which is to aid in choosing building construction components. The different methods will be discussed and compared to the 3E cost-‐C2C method.
In chapter 7 some benefits and drawbacks of the 3E cost-‐C2C method will be discussed
The research questions will be answered and conclusions will be drawn in chapter 8.
In the last chapter future development possibilities will be discussed.
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2 3E cost-‐C2C methodology This chapter presents the 3E cost-‐C2C methodology.
What the 3E cost-‐C2C method does is to analyse building components that affect the thermal performance of a building. It does this by summarizing the environmental, economical and energy performance from throughout their life cycle, after the performance values have been converted to costs, so one value is obtained. This value can be compared to the values of other building components with the same function, though not necessarily functionally equivalent, to determine which one is cheapest with regards to the 3E’s. Whole wall constellations can be compared. For example, walls with different insulations and insulation thicknesses can be compared. They are not functionally equivalent with regards to thermal performance, however this is taken into account in the energy part of the 3E cost-‐C2C method.
For all assessments of one wall constellation the functional unit and system boundaries should be the same, or at least consistent. Each assessment should be life cycle based and include the whole lifecycle to avoid trade-‐offs between life cycle stages, from cradle to cradle. C2C means from where the first raw materials are extracted to the end of life where the disposed product can either be reused, remade to a new product and is therefore the cradle for a new product, or disposed (Laszlo 2013, McDonough and Braungart 2002). This chapter will describe the 3E cost-‐C2C method further, starting with the environmental part and the conversion to cost with the Eco-‐cost method. Then the economical part will be explained followed by the energy cost calculation and then the summing up of all the values.
2.1 Life cycle assessment (LCA)
The environmental part of the 3E cost-‐C2C method is obtained with the LCA method and the Eco-‐costs method. The LCA method is a technique used to examine the environmental impacts associated with a product or service during every step of its life, from cradle to grave. These steps include general mining and production of raw materials, materials processing, manufacturing processes, distribution, use, maintenance, and finally disposal or recycling. Sometimes only a sample of life phases are studied, like cradle to gate (Baumann and Tillman 2004). LCA’s used for the 3E cost-‐C2C method should follow the ISO 14040:2006 and ISO 14044:2006 international standards (Silvestre et al. 2013).
LCA can be used for many purposes, among others (Baumann and Tillman 2004):
• To learn about the product life cycle and the environmental impact it generates.
• Identify within which life stage product gives rise to the greatest environmental impact (often it is not intuitive).
• Be able to make more informed decisions (for example when purchasing materials or products or in the context of product development).
• Promote their environmental commitment to customers.
Within LCA there are two types of studies: Accounting and change-‐oriented/consequential. In the first type existing systems and products are studied, data representing averages are used and as complete life cycles as possible are studied. The aim is to identify the environmental impact of the product in today's production and user system. The change-‐
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oriented/consequential type of LCA models the consequences of different choices, the study is forward-‐looking and often marginal data is used. The entire life cycle does not need to be included, but only those parts affected by the change (Baumann and Tillman 2004). The 3E cost-‐C2C method uses the accounting type of LCA (Silvestre et al. 2013).
For some environmental impact categories such as global warming, it is relatively easy to relate data on emissions to the environment. For other environmental impact categories such as toxicity and resource use it is not as easy due to the influence of a more complex nature. For example it is debated whether resource use should be considered an environmental problem or an economic problem. Within these environmental impact categories, there are many proposals for methods on how influence can be calculated or estimated, but no consensus (Baumann and Tillman 2004).
LCA looks at the environmental impacts of a product during a predetermined period of its life cycle, like from cradle to gate or cradle to grave. When the life cycle starts at “cradle” it means starting from the raw material extraction at the absolute start of production of a product. When the life cycle is to “gate” impacts up to the point where the product is finished and ready to be sold are included, at the gate of the factory. If the life cycle is to “grave” it includes the whole life cycle, including also the user phase and disposal phase (Baumann and Tillman 2004).
The four main phases of an LCA are (Baumann and Tillman 2004):
• Goal and scope
• Life cycle inventory
• Life cycle impact assessment
• Interpretation
2.1.1 Goal and scope
The first step in an LCA is to define the goal and scope of the assessment (goal and scope definition) and functional unit, the unit that all environmental impacts are going to be related to. The functional unit should describe the function of the assessed product (Baumann and Tillman 2004). The goal and scope are important parts of the LCA because they help narrowing down the often large amount of data that needs to be gathered to the essential data. For example, if the goal is to see which of two options has the smallest environmental impact, only data where the options differ needs to be collected. And the scope sets the system boundaries; data outside of the scope does not need to be included.
2.1.1.1 Goal
The goal of the LCA conducted for the 3E cost-‐C2C method is to obtain the life cycle impact assessment values so that the eco-‐cost of the product can be calculated.
2.1.1.2 Scope
The scope consists of the options to model, functional unit, choice of impact categories, method for impact assessment, system boundaries and allocation methods.
The functional unit for the 3E cost-‐C2C method can be defined as a square meter of external wall for 50 years. For a normal comparative LCA a functional equivalent must be established so that different alternatives can be compared, such as a square meter of external wall with a given heat transfer coefficient for 50 years. But with the 3E cost-‐C2C
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method there is no need for this, because the differences in function of the wall, the heat transfer coefficient, is taken in to account in the other parts of the 3E cost-‐C2C method. If a wall uses less insulation compared to another wall, thus different functional units, the energy cost will be higher throughout the user phase for that wall (Silvestre et al. 2013).
The impact categories and method for impact assessment of the LCA for the 3E cost-‐C2C method depend on the Eco-‐cost method and will be explained in chapter 2.2.
The system boundaries used in the 3E cost-‐C2C method is cradle to cradle, which is a concept for sustainable waste management that aims to utilize 100 % of the waste produced. This means looking into the possibility of, in first hand, reusing the product at the end of its life. If reusing the products is not an option then reusing the materials, or the last C2C option of getting energy out of the materials from combustion (Laszlo 2013).
In the EN 15804:2012 Core Rules for the Product Category of Construction Products for Environmental Product Declarations (EPD), the life cycles stages for construction products are standardized, se figure 1. These stages should be followed when using the 3E cost-‐C2C method (EN 15804:2012).
No allocation methods were discussed in the 3E cost-‐C2C method article by Silvestre et al. (2013).
2.1.2 Inventory analysis
The goal and scope definition is followed by an inventory analysis that involves the construction of a life cycle model and the gathering of data of all inputs and outputs that are associated with all stages of the life cycle. Inputs can be energy, raw materials and process chemicals. Outputs are waste, emissions to air and water, and products. Data collection is often one of the hardest and most time-‐consuming parts of an LCA. If multiple products are manufactured in the same process allocation problem will occur, which is how the inputs and outputs associated with the process shall be shared between the different products. In this thesis no such allocation problems occurred. This can be solved through either the basis of economic value, quantities or volumes produced (Baumann and Tillman 2004).
2.1.2.1 EPD data
If one is designing a house and wants to make a more informed decision when choosing materials and decides to use the 3E cost-‐C2C method, you need a lot of data to make a proper LCA. This data can often be hard to obtain, companies seldom want to give out such information without good cause. What a lot of companies have though is Environmental Product Declarations (EPD) for their products. These are public and often published on their websites, or on the International EPD® Systems website (http://www.environdec.com/). An EPD is a certified and registered document with transparent and comparative data about the products environmental performance over its whole life cycle. EPDs are regulated
Figure 1. Standardized product stages (EN 15804:2012).
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under ISO standard 14025:2006 international standards and the Europeans standard EN 15804:2012 (The International EPD® System 2015).
Figure 2. Calculation structure of an EPD according to En 15804 (Vogtländer 2014).
An EPD is a type of LCA presented in a special format based on common rules, known as Product Category Rules (PE International Sustainability Performance 2015). The results are presented for the different parts of the life cycle following standardized life cycle stages, as in figure 2, but can also be grouped together. Often A1-‐A3 are grouped together, probably so the company reveals less information about the manufacturing process or for simplicity. Unfortunately the EPD data is already organised in the EPD impact categories, so the data cannot be used to make your own LCA. But since the EPDs build upon the LCA method the data can be used, by using the EPD data to calculate the eco-‐costs straight away. This saves a lot of time and will be explained under the Eco-‐costs part, chapter 2.2.1.
2.1.3 Life cycle impact assessment (LCIA)
After the inventory analysis a Life Cycle Impact Assessment (LCIA) is carried out where emissions and resource use are categorised to different environmental impact categories. Often special LCA software’s with built-‐in databases are used. Examples of environmental impact categories are Energy and Materials, Global Warming, Ecotoxicological effects and Land Use. The number of impact categories vary with what LCIA method you are using. They differ with respect to the end-‐points, i.e. how far you look in the impact chain, as a type of environmental impact often gives rise to several others, which in turn can give rise to additional environmental impacts (Baumann and Tillman 2004). The impact categories for the Eco-‐cost method will be described in the Eco-‐costs part, chapter 2.2.
2.1.4 Interpretation -‐ weighting and single indicator
An LCA results in a long list of emissions from through out the life cycle which are then categorised in a impact categories, which is in turn a relatively long list of numbers that can be hard to interpret. It makes sense to try and compress these values to one single
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indicator, preferably an intuitive indicator that is easy to understand. So one last optional step in LCA is weighting, where the different environmental impact categories of relevance are judged against each other and weighted, and thus can be on the same scale. The result is a one-‐dimensional index, a single indicator. Since weighting is subjective (which impacts are most important) it is widely debated within the LCA literature (Baumann and Tillman 2004). The Eco-‐costs method is such an indicator.
There are many single indicators for LCA, and they can generally be divided into three categories:
• Single issue
• Damage based
• Prevention based
Carbon Footprint is the best known single issue indicator, where the total emission of CO2 and CO2 equivalents are added up. Single issue indicator calculations are simple and transparent, with no complex assumptions, and the results are easy to communicate to the public. But single issue indicators do not take other pollutants and resource depletion into account (The Model of the Eco-‐costs / Value Ratio (EVR) 2015).
Damage based indicators are the most common type of single indicators. Advantages are that they make companies and consumers aware of the environmental impact their production and consumption has. Disadvantages are that the systems are very complex, not transparent, need many assumptions and the weighting is subjective. Also, the results are not easy to communicate, since the results are expressed in points (The Model of the Eco-‐costs / Value Ratio (EVR) 2015).
Prevention based indicators, such as the Eco-‐costs method, are relatively new. The calculations are fairly simple and transparent and the result can be presented in economical terms or measures to be taken, which are easy to understand. The Eco-‐costs method focuses on the decision making process of architects, designers, engineers and business people (The Model of the Eco-‐costs / Value Ratio (EVR) 2015).
To calculate a single indicator in the classic way the pollutants are grouped in classes. The pollutants are multiplied by a characterisation factor, which represents the relative importance of the pollutants within the class. For example, CH4 (methane) is multiplied by 34 because it is 34 times more efficient as a greenhouse gas per kg compared to CO2, which is the baseline unit, with a time horizon of 100 years (Myhre et al. 2013). The emissions are then totalized in the groups to their midpoint effect. Midpoints are links in the middle of the cause-‐effect chain of an impact category of the environmental mechanisms (Bare et al. 2000).
2.2 Eco-‐costs method
The Eco-‐costs method weights the environmental impact categories obtained from the LCA with what it would cost to prevent such an impact. Or rather, what it would cost to prevent the pollution or material depletion to a level that is in line with the carrying capacity of earth. For example, if 1000 kg of CO2 is emitted, 135 € should be invested in offshore wind power (or other CO2 reduction systems at the same price or less). If everybody consequentially invested 135 € on reduction systems for every 1 ton of CO2 emission, the total CO2 emissions in the world would decline by 65 % compared to the 2008 emissions,
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thus stabilizing global warming. Therefore the eco-‐cost of 1 kg CO2 or CO2 equivalent emission is 0,135 € (The Model of the Eco-‐costs / Value Ratio (EVR) 2015).
Similar calculations can be made for acidification, eutropication, ecotoxicity, human toxicity, summer smog and fine dust. Also for the use of metals, rare earth, fossil fuels, water and land (nature). The eco-‐costs are virtual costs since they are not yet incorporated in the real life production cost (Life Cycle Costs) and should therefore be regarded as hidden obligations, so called “external costs”. The impact categories needed for the Eco-‐cost method are listed in table 1.
Table 1. The eco-‐costs for different impact categories from the Eco-‐cost 2012 system (The Model of the Eco-‐costs / Value Ratio (EVR) 2015).
Impact category Eco-‐cost (marginal prevention cost) Midpoint table
Acidification 8,25 €/kg SOx equivalent ILCD
Eutrophication 3,90 €/kg phosphate equivalent Recipe
Ecotoxicity 55,0 €/kg Zn equivalent UseTox
Human toxicity 36,0 €/kg Benzo(a)pyrene equivalent UseTox
Summer smog (respiratory diseases)
9,70 €/kg C2H4 equivalent Recipe
Fine dust 34,0 €/kg fine dust PM2.5 RiskPol
Global warming 0,135 €/kg CO2 equivalent (GWP 100) IPPC 2007, 100 years
Beyond the eco-‐costs of the insulation the eco-‐costs of the energy used to heat and cool the building needs to be added. This can be calculated with the same formula as for the energy cost calculation, see equation 1, but instead of T (electricity cost) the eco cost of electricity is used. The eco-‐costs of energy can be found in the Idemat2015 Excel data sheet on the Eco-‐costs website (The Model of the Eco-‐costs / Value Ratio (EVR) 2015). The Ecocosts2012_V3.3_LCA_data_on_products_and_services_EI_V3_Idemat2015 version was used in this thesis. There is Ecoinvent V3 data for eco-‐costs of electricity by country mix for high, medium and low voltage. Medium voltage for the Swedish electricity mix was used.
2.2.1 Using EPD data
If you have an EPD of the product you are examining it is quite simple to calculate the eco-‐costs. There are two methods for this described in the Appendix VI in Vogtländers book, method A and method B (Vogtländer 2014). They follow the model of the Eco-‐costs / Value Ratio (EVR), but use EPD data for the calculation (The Model of the Eco-‐costs / Value Ratio (EVR) 2015). The method used in this thesis is method B, because the three insulations fulill the requirements for this method and the data for the method is supplied in the EPDs. Method A will not be discussed because the data needed for this method was not supplied in the acquired EPDs, and thus this method could not be used.
17
The EPD data is grouped in the impact categories shown in table 2.
Table 2. The relationship between the impact categories in EN 15804 and Eco-‐costs (Vogtländer 2014).
Impact Category in EN 15804 Eco-‐costs Quantity and Unit
Acidification for soil and water 8,25 € 1 kg SO2 equiv.
Ozone Depletion 0,000 € 1 kg CFC 11 equiv.
Global Warming 0,135 € 1 kg CO2 equiv.
Eutrophication 3,90 € 1 kg (PO4)3-‐ equiv.
Photochemical ozone creation 9,70 € 1 kg Ethane equiv.
To acquire the eco-‐cost with EPD data you multiply the emission stated in the EPD data with the eco-‐cost of that impact category, do the same thing for the other impact categories, and then add the eco-‐costs of resource depletion for the materials used in the product (Vogtländer 2014). The eco-‐costs of resource depletion can be found in the Idemat2015 Excel data sheet on the Eco-‐costs website (The Model of the Eco-‐costs 2015).
To use Eco-‐costs calculation method B the products need to be made from only renewable or non-‐scarce materials, where the eco-‐cost of metals depletion is negligible (Vogtländer 2014). Rock wool, EPS and cellulose fibre all fulfill this, being made primarily of stone, oil and recycled newspapers, oil being relatively non scarce.
2.3 Whole-‐life costing (WLC) method
The economical part of the 3E cost-‐C2C method is based on the Whole-‐life Costing method and follows most principles of the EN 15643-‐4:2012. The major part of the economical cost is the market acquisition cost in year 0, which is the sum of manufacturing, transportation of the products to the site and the installation cost of the product. The costs should be presented without the value added tax (VAT) (Silvestre et al. 2013). During the use stage, year n, there are cost of maintenance, repair and replacement of the wall. For just the insulation there are no costs during the use stage. The economic cost in the end-‐of-‐life stage, year 50, only includes the transport and disposal costs of the examined building assembly waste and expenses and/or revenues from reuse, recycling or energy recovery.
2.4 Energy cost calculation
The energy cost is calculated with equation 1 (Silvestre et al. 2013). The size of the building, heating and cooling needs, efficiency of heating/cooling system, electricity cost and the rate of use of heating/cooling need to be known. For the calculation electricity should be assumed to be the heating method for the building.
Equation 1.
€
Cegn = K ⋅ T⋅ Nicηi
+Nvcηv
⎛
⎝ ⎜
⎞
⎠ ⎟ ⋅AapAew
18
Cegn = Energy usage cost. Cost for energy in year n per m2 of external wall, depends on
house. [€/(m2•year)]
K = Represents the rate of use of heating and cooling systems in the residential building as a percentage of the year.
T = Cost of 1 kWh of electricity for a Swedish household, without Value Added Tax (VAT) or standing charges. [€/kWh]
Nic = Nominal annual heating needs per square metre of net floor area of the flat or house. [kWh/(m2•year)]
€
ηi = Nominal efficiency of the heating equipment.
Nvc = Nominal annual cooling needs per square metre of net floor area of the flat or house. [kWh/(m2•year)]
€
ηi = Nominal efficiency of the cooling equipment.
Aap = Net floor area of the flat or house under assessment. [m2]
Aew = Total area of the external wall being assessed. [m2]
Only energy costs during the use stage are included, the energy needed to heat the building. The energy used in production and construction stage is assumed to be covered in the price of the product so covered in the WLC. The energy consumed or recovered in the end-‐of-‐life stage is also covered in the WLC. Therefore these costs/benefits are not added to the energy cost because this would result in double counting.
2.5 Summing up with the Net Present Value (NPV) method
Costs occur during different times of the life cycle. To account for this and get a total cost for today, the design phase at year 0, the Net Present Value method is used, se equation 2. The NPV is a sum of all the costs in different years of the study period after they have been discounted, assuming constant prices (Silvestre et al. 2013).
Equation 2
€
NPV =Cn
(1+ d)nn=0
50
∑
NPV = Net Present Value per m2 of external wall over 50 years. [€/m2]
n = Year.
Cn = Cost in year n. [€/m2]
d = Real discount rate applied (without considering risk), 3 %.
The cost Cn is the sum of the 3E costs, se equation 3.
Equation 3
€
Cn = Cevn +Cecn +Cegn
Cevn = Environmental damage cost in year n per m2 of external wall, based on LCA. [€/(m2•year)].
19
Cecn = The economical cost in year n per m2 of external wall, acquisition and disposal cost, based on WLC. [€/(m2•year)].
So all the 3E’s are discounted. When making the calculations in this thesis the NPV of each year n were not calculated, as in equation 3. Instead the total NPV of each of the three E’s was calculated. This made more sense when calculating and resulted in nice graphs where for example the environmental costs of the three insulations could be compared. Calculating in this way yields the same correct result.
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3 Thermal insulation materials This chapter presents the three insulations that are examined with the 3E cost-‐C2C method and why they were chosen. Two aspects that are not considered in the 3E cost-‐C2C method are also explained, the fire class and the vapour water diffusion factor.
The insulations to model are rock wool, polystyrene and cellulose fibre. The products selected fulfil the same function yet have different life cycles. Rock wool and polystyrene foam panels are two of the most commonly used conventional insulations in the passive house industry, but they represent two relatively different types of insulations. Cellulose fibre is considered an environmentally friendly option on the rise. These insulation options have been chosen through consultation with Anders Linde at Passivhuscenter, who is an Architect and Certified Passive House Designer. Also in Duijves (2012) report the author concluded that out of the insulations he studied (glass wool, rock wool, EPS, Flax, Hemp, PF-‐foam, PUR, PIR) after disregarding the rest (VIP, aerogel, coconut, foam glass, cork, perlite, wood wool, cellulose fibre, recycled cotton, sheep wool, XPS) the three best options with regards to technical, environmental and health aspects for application in building renovation to passive house standards where glass-‐ and rock wool together with EPS (Duijve 2012). See figure 3 for a plot of material thickness against prices from the Netherlands from 2012.
Figure 3. Price and thickness in order to reach RC = 3,5 m
2K/W (Duijves 2012).
The reason Duijves disregarded cellulose fibre was “Since cellulose insulation is hard to use in a cavity wall (needs good support and rain shelter)” (Duijves 2012). But this would not be a problem if it were used in the construction of a new building.
21
3.1 Thermal conductivity
Houses are mainly insulated to reduce the heat flow from inside to the outside of the house when it is cold outside, and reduce the flow in the opposite direction when it is warm outside. The building envelope, the barrier that stands between the inside and outside air, must have a high thermal resistance (R) to reduce heat loss. R has the unit Km2/W. Insulating materials are materials with high thermal resistance, and how efficient they are is determined by the thermal conductivity (λ) in W/m·∙K. Thermal conductivity can be seen as a measure of how efficient a material is at conducting heat, the lower the conductivity the better it insulates. The thermal conductivity is needed to calculate the heat flow through a wall with equation 4 (ElectronicsTeacher.com 2015):
Equation 4.
€
Q = λ⋅ΔTd⋅ A = k⋅ ΔT⋅ A
In which:
Q = Heat flow [W]
ΔT = Temperature difference across the material [K]
d = Thickness of the material [m]
A = Surface area of the material [m2]
λ = Thermal conductivity of the material [W/m·∙K]
k = Heat transmission coefficient (λ/d) [W/m2·∙K]
From equation 4 we can see that a lower λ will reduce the heat flow. We can also see that k = λ/d, which when inverted gives the thermal resistance for a certain material thickness. The thermal conductivities of the three insulations are relatively similar: rock wool and EPS has a λ = 0,035 W/m·∙K and cellulose fibre has a λ = 0,039 W/m·∙K (Paroc AB EPD 2014, EUMEPS region Scandinavia EPD 2013, ISOCELL GmbH EPD 2014).
3.1.1 Insulating air
The material of the insulation is not what insulates. It is the microscopically small air or gas pockets that the insulation creates that give the low thermal conductivity. The cell pockets keep the air stable so no mixing can occur and therefore the convective heat transfer is suppressed. So the thermal conductivity of the air or gas within the insulation sets the theoretical thermal resistance limit of insulation. This means that the gas within the insulation is an important aspect of the material. Another option is to not use gas at all, but work with near vacuum, as with vacuum insulation panels, although this will not be discussed in this thesis (Duijve 2012).
3.1.2 Density
A higher density results in a higher thermal conductivity because there is more material to conduct the heat and less air to resist the heat, at least beyond a certain point. But for some areas the insulation needs to be self-‐supported or have higher compressive strength, such as flat roofs and cavity walls (Duijve 2012). A denser structure means higher compressive strength, but also higher thermal conductivity.
22
3.2 Fire class
All building materials must have a fire class; it is part of the CE-‐marking that is obligatory for building materials and is described in the European norm EN-‐13501-‐1. The fire class can be of relevance when choosing insulation for certain projects. There are seven main classes, A1 which is the highest class, non-‐flammable, to A2, B, C, D, E which is highly flammable and F which is either extremely flammable or not yet specified. There are also two other classes besides the main class, smoke growth rate (s1, s2 or s3) and flaming droplets or particles (d0, d1 or d2), but these will not be discussed in this thesis (Paroc.se 2015).
Even if a material is fire class E or F it can still be used, as long as the whole construction reaches the requirements, because it is the entire construction that is assessed for its fire class. The requirements may differ for different residential functions and construction types, but the minimum requirement for the whole building is classification D-‐s2, d2 for homes and assembly halls in Sweden (BBR 21).
3.3 Water vapour diffusion factor
It is important to consider the moisture when constructing the buildings envelope, or water damage could become a problem. Water vapour can condense inside the wall when going from the warm inside to the cold outside and can lead to structural damage with rotting wood or mould issues. Showering, plants, cooking and the humans are contributors to the high humidity inside the buildings. The vapour pressure becomes higher inside the house than outside, this leads to the diffusion though the walls since the diffusion cancels out the unbalance (Vapour resistances and μ-‐values BuildDesk 2015).
To determine how god a material is at resisting the vapour the Water vapour diffusion resistance factor (μ) is used. The μ value of a material is calculated with equation 5:
Equation 5. How to calculate the water vapour diffusion resistance factor (Vapour resistances and μ-‐values BuildDesk 2015).
€
µ= vapour diffusion resistance of a material with thickness d , , vapour diffusion resistance of an air layer with thickness d
This factor gives a good first impression of an insulation’s vapour diffusion resistance, which can have practical applications. The μ is equal to or greater than 1, the higher the better vapour resistance, so when building a vapour-‐closed construction materials with a high μ are required. Some insulations have a low μ, close to 1, but these insulations are often used in combination with a vapour barrier so the water does not reach the insulation, for example PE-‐foil which has a μ of 50 000 (Duijve 2012).
3.4 Rock wool
Mineral wools are fibre materials that are formed by spinning or drawing molten minerals, like rock wool, glass wool and slag wool. The combined European insulation market share of glass-‐ and rock wool is around 60 % (Pappadopoulus 2005). Rock wool (or stone wool, same thing), se figure 4, is made from volcanic rock, typically basalt or dolomite and an increasing proportion of recycled material (Paroc AB EPD 2014). Also slug residues from the metal industry can be added. It is available with different thermal conductivities and densities and can be used in diverse parts of the building and industrial process.
23
Stone wool is made in a furnace at about 1600 °C, coke is used to fuel the oven. Steam or air is blown through to create the wool structure (Kowatsch 2010). A more advanced method is to spin the molten rock at high speeds, basically like you make cotton candy. The molten minerals are poured on to a spinning disk through which air is blown. The result is fine intertwined fibres with a diameter typically between 6 and 10 micrometers. The fibres are bonded with a bounding agent, phenol-‐formaldehyde-‐urea resins and abatement oil, to create panels, flocks or rolls (Kowatsh, 2010). It consists to 96-‐98 % of natural stone, the rest is the organic binder (Parocs.se 2015).
Figure 4. Rock wool insulation from Paroc (Paroc AB EPD 2014).
3.4.1 Thermal conductivity and density
The thermal conductivity for rock wool is typically between 0,03 and 0,04 W/mK according to Jelle (2011). The two biggest producers of rock wool in Sweden are Paroc AB and Rockwool. Their products have a thermal conductivity of 0,035 and 0,037 W/mK respectively (Paroc AB EPD 2014, Rockwool EPD 2009).
The density of rock wool is usually in between 25 and 200 kg/m3, for the Paroc and Rockwool products mentioned above the densities are 35 and 32 kg/m3 respectively (Paroc AB EPD 2014, Rockwool EPD 2009). The higher densities occur when the rock wool is compressed into panels for when there is a need for higher compressive strength.
3.4.2 Fire class
Rock wool meets the highest European fire class standard of Euroclass A1 (Paroc.se 2015). The primary products are usually a good indicator of the fire class, and since rock wool is made from inorganic materials it does not burn easily. It does not smoke or produce flaming droplets. But, rock wool panels or rolls can be layered with materials for moisture control or extra insulation that can lower the fire class.
3.4.3 Other aspects
• Water vapour resistance factor:
€
µ = 1 (Papadopoulos et al. 2005)
• Rock wool also has good sound absorbing properties and thus reduces both sounds coming in and going out through the wall.
• Can be used for insulation in basically all types of building envelope.
24
• When installing it must be kept dry. An increase of moisture content from 0 to 10 % will result in an increase of the thermal conductivity from 0,037 to 0,055 W/mK, which is an increase by almost 50 % (Jelle 2011).
• Not renewable.
3.5 Expanded polystyrene
EPS is made from the petroleum products benzene and ethylene. Benzene and ethylene are used to produce the monomer ‘monostyrene’. Monostyrene is polymerized with the blowing agent pentane and possibly a flame retardant like hexabromocyclododecane to polystyrene beads. The beads, also called polystyrene granulates, are expanded in an expansion chamber and then cast in a mould under steam pressure to a block. The heat and pressure makes the granulates melt together. The used pentane is replaced by air during and after the process. After storage the block can be cut with filaments to the desired dimensions. The expanded and moulded product is form-‐stiff and has a micro pours structure (Sundolitt Produktguide 2010).
Figure 5. The closed cell structure of EPS (Sundolitt.se 2015).
The closed cell system has a low internal convection, low permeability for air and low water absorption, se figure 5 (Sundolitt.se 2015). Large panels can be constructed due to the dens cell structure, se figure 6.
Figure 6. EPS boards by Sundolitt (Bygghemma.se 2015).
25
3.5.1 Thermal conductivity and density
The lowest thermal conductivity for EPS is achieved at densities between 30 and 50 kg/m3, se figure 7 (Sundolitt Produktguide 2010).
Figure 7. How thermal conductivity, Y-‐axis, depends on density, X-‐axis, for EPS (Sundolitt
Produktguide 2010).
With lower densities the material is more permeable to heat radiation. The thermal conductivity of EPS ranges from 0,033 to 0,041 W/mK (Sundolitt Produktguide 2010). The EPS studied in this thesis has a density of 20 kg/m3 and a thermal conductivity of 0,035 W/mK (EUMEPS region Scandinavia 2013).
3.5.2 Fire class
The Swedish EPS producer Paroc AB does not use flame-‐retardants because the chemicals are a health hazard and not environmentally friendly (Sundolitt Produktguide 2010). When not treated the fire class is F, when treated the fire class is E. When shielded in a wall the construction can reach fire class B (Sundolitt.se 2015).
3.5.3 Other aspects
• Water vapour resistance factor:
€
µ = 30-‐70 (EUMEPS region Scandinavia 2013).
• Can be used to insulate walls, roofs and concrete floor.
• Since EPS is form-‐stiff it can support itself and also be used as a moulding cast for concrete foundations. Compressive strength of EPS examined in thesis was 100 kPa (EUMEPS region Scandinavia 2013).
• Loose pearls that are not moulded can be used to fill existing cavity walls (Sundolitt Produktguide 2010).
• Not renewable.
3.6 Cellulose fibre
Cellulose fibre insulation is made from recycled paper, usually newspapers (Miljöbyggsystem.se 2015). The main material is therefore wood, which has been used in buildings for thousands of years. The paper material is sorted, shredded and then grinded together with mineral salts in a mill. The obtained flakes are resistant to fire, mold and vermin due to the mineral salt and does not rot (Isocell.at 2015). Cellulose fibre can be produced either as panels or as loose fibres that are blown in, se figure 8. In this thesis the data collected was for the “blown in” version because that is the main product of Isocell and their EPD was for blown in insulation. The benefit of blown in insulation is that the
26
insulation forms into a tailor-‐made insulation for the construction (Miljöbyggsystem.se 2015).
Figure 8. Blown in cellulose fibre (ISOCELL GmbH (2014).
3.6.1 Thermal conductivity and density
The thermal conductivity of cellulose fibre insulation is around 0,039 W/mK (ISOCELL GmbH 2014). The density can vary depending on for example where it is installed. If in a wall it will be more compressed and the density will be higher and on a roof it will have loose layers and a lower density. The density can range from 28 to 65 kg/m3 (ISOCELL GmbH 2014).
3.6.2 Fire class
The fire classification is Euroclass E if the insulation thickness is 40 – 100 mm and Euroclass B if thicker than 100 mm (ISOCELL GmbH 2014).
3.6.3 Other aspects
• Water vapour resistance factor:
€
µ = 1 (ISOCELL GmbH 2014).
• Cellulose fibre can be used for most types of insulation applications and soundproofing.
• Is marketed as an environmentally friendly option (Miljöbyggsystem.se 2015).
• Renewable.
27
4 Scope of the 3E cost-‐C2C analysis of insulations The scope of the analysis is defined and explained here. First the functional unit is defined, then the lifecycles including what manner of disposal to calculate, the timeframe, what geographic areas to focus on and what environmental impacts to include. Lastly an example house is defined, the VAT is discussed and the manufacturers chosen to represent the insulations are presented in short.
4.1 Functional unit
For the 3E cost-‐C2C the functional unit is ‘a square meter of external wall for 50 years’. Since the method takes the whole C2C life cycle into account different types of walls and wall thicknesses can be compared. But if the three insulations are to be compared fairly, they should also be functionally equivalent. So the functional unit for the first comparison is the heat transfer coefficient U measured in W/m2K for 1 m2 of wall insulation to achieve passive house standard in Sweden, which is approximately 0,1 W/m2K for wall insulation. It varies depending on the rest of the structure of the house, but the general rule is that the insulation should achieve 0,1-‐0,15 W/m2K in a passive house, with 0,15 W/m2K as a minimum requirement in cool temperature climates (International Passive House Association 2015). This means that no more than 0,15 watts of heat energy should be lost though the external envelope of the house per square meter and degree Kelvin. For single-‐family homes, which are freestanding buildings, the U-‐value is often under 0,1 W/m2K, and therefore ‘a square meter of external wall for 50 years with U = 0,1 W/m2K’ was chosen as the functional unit for the passive house (International Passive House Association 2015).
Once all the data was collected in Excel for the passive house standard comparison it was simple to also make a comparison with the costs for a regular Swedish house.
4.2 Lifecycle
Preferably the whole life cycle from C2C would be included for all insulations, but depending on what data can be obtained this may vary. The EPDs for the three insulations cover the areas shown in figure 9 (Paroc AB 2014, EUMEPS region Scandinavia 2013, ISOCELL GmbH 2014).
These data follow the calculation structure of an EPD according to EN 15804.
Figure 9. Areas covered in the EPDs (Paroc AB 2014, EUMEPS region Scandinavia 2013, ISOCELL GmbH 2014).
28
Often the Use stage is excluded when making an EPD for insulation (Paroc AB 2014, EUMEPS region Scandinavia 2013, ISOCELL GmbH 2014). This is probably because there are no environmental impacts from the insulation when it operates in the wall, which was confirmed by all the manufacturers123. If there are no environmental impacts there probably are no economical costs either. The assumption is that basically anything that would yield a cost would also yield an environmental impact. Therefore the cost contribution of insulation of the whole Use stage was set to zero.
4.3 Time frame
The time frame of the insulations life cycles is from C2C, so from the raw material extraction to end of life with recycling or some kind of disposal. The time horizon for the house, and therefore the insulation, is sett to 50 years, as this is often the practice when calculating on the life cycle of buildings and building materials (EN 15804:2012). Also the reference service life for the insulations is 50 years in the EPDs.
4.4 Geographic boundaries
The geographical focus of the study will be on insulations sold on the Swedish market, so preferably the data will be from Swedish manufacturing facilities using Swedish raw materials. If data for Swedish manufacturing cannot be obtained for one of the insulations the data that was obtained should be applicable for the Swedish market.
4.5 Environmental impact categories
The environmental impact categories that are going to be used in this thesis are the ones used in the EPDs. The impact categories are:
GWP = Global warming potential [1 kg CO2 equiv.]
ODP = Depletion potential of stratospheric ozone layer [1 kg CFC 11 equiv.]
POCP = Formation potential of tropospheric photochemical oxidants [1 kg Ethane . equiv.]
AP = Acidification potential of land and water [1 kg SO2 equiv.]
EP = Eutrophication potential [1 kg (PO4)3-‐ equiv.]
This is convenient as there are conversion factors to convert the EPD impact categories to eco-‐costs, se table 2.
4.6 Example house
For some of the calculations in the energy and economical parts the size of the house needs to be defined. For example when calculating the energy cost using equation 1, the total floor area and the total external wall area needs to be defined. Also the total amount of wall insulation is needed to calculate transportation and disposal costs. The Swedish Energy Authority supplied data for the Swedish average house for year 2013 (Energimyndigheten
1 Mikael Olofsson, Technical Adviser at Paroc AB, mail conversation 2015-03-31. 2 Emil Syrèn, Product & Marketing Manager at Sundolitt, mail conversation 2015-‐04-‐13.
3 Andreas Östlund, VD/CEO at Miljöbyggsystem MBS AB, phone conversation 2015-‐03-‐11
29
2015). The average house living area was 152 m2, but there were no dimensions specified. So the dimensions 7,6 meters wide, 10 meters long, 2 floors and a outer wall height of 5 meters were defined for the house, as this seems like reasonable dimensions and
€
7,6⋅ 10⋅ 2 =152 . This results in a wall area of
€
(7,6 +10)⋅ 2⋅ 5 =176 m2. The total wall area multiplied with the insulation thickness gives the total amount of insulation needed for the walls of the house.
An arbitrary location for the building also needs to be defined to be able to calculate the different transportation costs. Lerum was chosen as a location, 21 km outside of Gothenburg.
4.7 Value Added Tax
Even though the economical cost should be calculated without the VAT according to Silvestre et al. (2013), for this thesis the calculations have been made including the VAT. There are four reasons for this:
• The tax will be a cost for the owner of the building one way or another, for both the economical and energy part, but there is no tax for the environmental cost. So if the relative cost between the 3E’s is going to be correct, the tax needs to be included.
• As long as the VAT is included in all the compared insulations the relative results between the economical and energy parts should be the same as without VAT.
• The imagined house being built is a regular sized stand alone family house, so it is plausible that the insulation was not bought through a contractor, and then the VAT should be included.
• In Sweden the VAT is often already included in the price.
4.8 Manufacturers
The rock wool insulation is represented by Paroc AB stone wool insulation with a density of <70kg/m3. Paroc AB is on of the largest producers of rock wool in Sweden with approximately 2/3 of the rock wool market4. Rock wool has approximately 1/3 of the total market for insulation1.
The EPS foam insulation is represented by Sundolitt, one of the leading producers of EPS in Sweden5.
The Swedish manufacturer ISOCELL who is represented by Miljöbyggsystem MBS AB on the Scandinavian market represents cellulose fibre. ISOCELL is the largest producer of cellulose insulation in Europe (Miljöbyggsystem.se 2015).
4 Mikael Olofsson, Technical Adviser at Paroc AB, mail conversation 2015-‐02-‐13.
5 Anders Linde, Arkitekt SAR/MSA and certified Passive House Designer at Passivhuscentrum i Västra Götaland, mail conversation 2015-‐
02-‐04
30
5 Results of the insulation evaluation In this chapter the insulations will be analysed with the 3E cost-‐C2C method. Every step of the process will be explained to deepen the understanding.
5.1 Environmental impact cost
The environmental costs were obtained through the Eco-‐Costs method using EPD data together with the recourse depletion cost and the eco-‐cost of the energy used for heating the building in the Use stage of the product.
5.1.1 EPD data
The EPDs were obtained through the manufacturers websites and the EPD data was transferred to Excel for further calculation. All the EPDs comply with the ISO 14025 and EN 15804 standards and had 50 years as reference service life. All three insulations can be reused at the end-‐of-‐life, if not damaged, but in the EPDs landfill and/or incineration was used, and therefore the EPD option was chosen as end-‐of-‐life scenario for this thesis (Paroc AB 2014, EUMEPS region Scandinavia EPD 2013, ISOCELL GmbH 2014). Since the end-‐of-‐life scenario is discounted for 50 years the cost impact of the disposal option is a relatively small part of the total cost, so the cost difference between the disposal option used in this thesis and a reuse or recycling scenario would probably not be big.
The calculations made to transform the EPD data with different declared units to the functional unit of 1 m2 of wall insulation with thickness to reach the Swedish passive house standard are shown in table 3.
Table 3. Calculations to transform EPD data to functional unit (Paroc AB EPD 2014, EUMEPS region Scandinavia EPD 2013, ISOCELL GmbH EPD 2014).
Thermal conduct-‐ivity (
€
λ )
Thickness for passive house standard, U = 0,1 W/m2K
Declared unit in EPD
Thickness of declared unit
Transformation of EPD data to U = 0,1 W/m2K
Rock wool
0,035 W/mK
€
λ /U = 0,035/0,1 = 0,35 m = 35 cm
1 m2 with R = 1 Km2/m
€
R⋅ λ = 0,035 m
Data•10 = Functional unit
EPD 0,035 W/mK
35 cm 1 m2 with R = 1 Km2/m
0,035 m Data•10 = Functional unit
Cellulose fibre
0,039 W/mK
39 cm 1 m3 1 m Data•0,39 = Functional unit
5.1.1.1 Rock wool
Parocs EPD represents Paroc insulation with densities lower than 70 kg/m3, with the average density of 35,1 kg/m3. The rock mineral wool production was modelled based on site specific data from production plants in Hällekis and Hässlehom, Sweden, and Pargas, Oulu and Lappeenranta, Finland. The Gabi 6 Software System for Life Cycle Assessment was used for the calculation and all the relevant background data were taken from the Gabi 6 software, referring to the years 2009-‐2012. The stone wool is made primarily by volcanic rock, normally basalt or dolomite, but an increasing proportion consists of recycled material (Paroc AB EPD 2014).
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The EPD covers the following steps in the production stage, module A1-‐A3 (Paroc AB EPD 2014):
• Production of raw material
• Binder components production
• Transport of raw material and pre-‐products to manufacturing plant
• Product manufacturing (power, thermal energy, manpower, emissions)
• Packaging materials production
• Water treatment, waste management, end-‐of-‐life of residues
The other modules are calculated on the basis of scenarios or assumptions (Paroc AB EPD 2014):
• Module A4: transport to the building site, 500 km
• Module A5: waste generated during the installation is assumed to be 0 %
• Module C2: transport to the End of life, 50 km
• Module C4: landfill
Module D includes reuse, recovery and/or recycling potentials. According to EN 15804 any declared benefits or loads from net flows leaving the product system that are not allocated as co-‐products and have reached and passed the waste state shall be included in module D. The cut-‐off criteria is 1 %, so production processes and energy flows smaller than this are not included, except for hazardous materials and substances. All major raw materials and energy is included (Paroc AB EPD 2014).
Parocs EPD had 1 m2 stone wool with a thermal resistance (R) of 1 Km2/W without any lamination as declared unit (Paroc AB EPD 2014). The thermal conductivity of rock wool is
€
λ = 0,035 W/mK. See table 3 for the transformation of EPD data to the functional unit of 1 m2 of wall insulation with passive house thickness for Sweden of U = 0,1 W/m2K for 1 m2.
5.1.1.2 EPS
The European Association of EPS (EUMEPS) of which Sundolitt is a member made the EPD for EPS. The data for the EPD was provided by a representative mix of three manufacturers of EUMEPS members in Scandinavia, based on production during 2011 (EUMEPS region Scandinavia EPD 2013). The foam structure consists of 98 % air and 2 % polystyrene and is available in various dimensions and shapes. EPS foams are made of polystyrene, which makes up 95 % of the weight, and blown in pentane, which represents the rest. The pentane is released during the production or shortly after. Normally no other substances are added. Polystyrene and pentane are made from oil and fossil gas. The EPD is valid for homogeneous EPS products (EUMEPS region Scandinavia EPD 2013).
Module A1-‐A3 covers the production and transport of the basic materials, manufacture of the product and the packaging materials. A4 covers transport of the products and A5 the packaging materials. Gained energy from packaging incineration is declared in module D (EUMEPS region Scandinavia EPD 2013).
There are two end-‐of-‐life scenarios in the EPS EPD, “Incineration” and “Landfill”. Both scenarios include transport to the end-‐of-‐life stage, C2. In the incineration scenario 100 %
32
of the waste EPS is incinerated and the effort and emissions of the process is declared in module C3. Resulting energy is declared in module D. In the landfill scenario 100 % of the waste EPS is put on landfill and the effort and emissions of the process is declared in module C4 (EUMEPS region Scandinavia EPD 2013). In some graphs in this report the different end-‐of-‐life scenarios are presented separately. Where they are not and there is only one EPS declared, 50 % of the waste EPS has gone to incineration and 50 % has gone to landfill. We cannot be sure today of how the waste will be handled 50 years from now. As can be seen in figure 10, the difference in eco-‐cost between incineration and landfill is not great.
The declared unit is Expanded Polystyrene rigid foam without flame retardant, with density of 20 kg/m3 per 1 m3 and per 1 m2 with R-‐value 1 (EUMEPS region Scandinavia EPD 2013). The data for 1 m2 with R-‐value 1 was used, the same as for rock wool. The thermal conductivity of EPD is
€
λ = 0,035 W/mK, also the same as for rock wool, so the same scaling of EPD data is made as for rock wool, see table 3.
5.1.1.3 Cellulose fibre
Cellulose insulation by ISOCELL Gmbh from two production sites in Hartberg (Austria) and Amel (Belgium) supplied the data for the EPD representing cellulose. There was no EPD for production of cellulose fibre in Sweden, but Andreas Östlund3 explained that the production process is the same for the ISOCELLs factory in Tibro (Sweden) as for the Hartberg and Amel, although the Swedish factory is newer and electricity used in Sweden is probably cleaner. The data is from production between July 2012 to July 2013 and the average from the two production sites was used. The average variance of the results between the two sites is 5,8 %. SimaPro 8 software was used for the calculation and the database Ecoinvent v. 2.2 was used for background data. The cellulose insulation consists of reused grinded newspapers, >90 %, mixed with mineral salts, <7 %, and boric acid, <3 %. The mineral salts and boric acid work as fire protection agents (ISOCELL GmbH EPD 2014).
Data for all energy consumptions, waste amounts and packaging materials were collected. Data for infrastructure was not collected. No other data was known to be missing. Using waste paper leads to a reduction of primary raw material consumption and to energy savings, as no new cellulose fibre needs to be produced. Since waste paper is a secondary material the collection and sorting is attributed to the previous product system. The raw material for boric acid is mined in Turkey, and for the transport it is assumed that 50 % is delivered by truck and 50 % by ship. The insulation is packed in polyethylene bags of approximately 12,5 kg and stacked on reusable pallets of 21 bags per pallet. There was no data for the transport to site and the installation so the A4 and A5 modules are not declared. The scenario Thermal waste treatment was chosen to represent the end-‐of-‐life stage in the EPD (ISOCELL GmbH EPD 2014).
The ISOCELL Gmbh EPD gives two sets of results: for the minimum nominal density of 28 kg/m3 and the maximum nominal density of 65 kg/m3. After consulting Andreas Östlund3 an average between the two densities of (28+65)/2 = 46,5 kg/m3 was chosen to represent cellulose fibre. Östlund explained that the density of cellulose insulation in walls is higher than if on the ceiling, so he recommended calculating with an average of about 45 kg/m3 (ISOCELL GmbH EPD 2014). If the density of cellulose fibre insulation is not defined it is 46,5 kg/m3.
33
One cubic metre of insulation material (m3) was defined as declared unit. The thermal conductivity of cellulose insulation is
€
λ = 0,039 W/mK (ISOCELL GmbH EPD 2014). The calculation of EPD data to the functional unit is shown in table 3. The data from the EPD was first adjusted to averages of the 28 kg/m3 and 65 kg/m3 densities and then multiplied by 0,39 to attain the data in the functional unit.
5.1.2 Eco-‐costs method
After the EPD data has been scaled to 1 m2 of insulation with U = 0,1 W/m2K the emissions are summed up, within the different impact categories, in two groups of when the emission takes place. Emissions in the production and construction stages take place in the beginning of the life cycle, before use, and emissions in the end-‐of-‐life and benefits and loads stages take place after use, 50 years later. Some benefits and loads in module D may occur in the beginning of the life cycle, but for simplicity they are assumed to take place at the end of the life cycle since the majority of the benefits and loads probably occure then. The reason for deviding up the data in this way is because the cost of emissions at the end of the life cycle need to be discounted.
The emissions are then multiplied with the eco-‐cost of that impact category, see table 2. The eco-‐costs of the C and D modules are discounted for 50 years, so the NPVev(C+D) = Cev50/(1+0,03)
50. The environmental cost are then added up together with the recource depletion cost and the eco-‐costs of energy used to heat up the building. The result can be seen in figure 10.
EPS has the largest environmental damage cost, regardles of disposal method. The recource deplition cost is a larg part of the environmental cost for EPS, wheras for rock wool and cellulose fibre it is relatively small. Rock wool has the second largest enveronmental cost,
2 € 3 € 3 €
-‐ 1 €
-‐ 3 €
0 €
1 € 1 €
0 € 0 €
1 €
0 € 0 €
0 € 0 €
0 €
5 € 5 €
0 € 0 €
0 €
0 € 0 €
0 € 0 €
-‐4€
-‐2€
0€
2€
4€
6€
8€
10€
Rock Wool EPS Incineradon EPS Landfill Cellulose 28kg/m3 Cellulose 65kg/m3
Total discounted environmental cost
Energy to heat building Recource Depli�on EP
AP
POCP
GWP
Figure 10. This graph shows the total eco-‐costs of the insulations for 1 m2 with passive house thickness.
34
global warming being the largest contributor. Cellulose fibre has a net benefit for the environment because of the larg negative cost from the GWP, probably due to being made primarily from recycled material. The recycled newspapers would probably have been disposed in some other maner if not used, maybe incineration, and now this disposal gets prosponed. For all thre insulations the envirnmental impact categories not metiond have small cost contibutions.
The recourc deplition is obtained from the Idemat2015 Excel data sheet found on the Eco-‐costs website (The Model of the Eco-‐costs 2015). For rock wool the recourse depletion value of Idemat 2015 Rockwool was used. For EPS the recourse depletion of Idemat 2015 PS (EPS, expandable polystyrene) was used. For cellulose fibre there were no Idemat values, but included in the Excel data sheet were also values from Ecoinvent V3, another database with life cycle inventory data. So the Ecoinvent V3 recourse depletion value of Cellulose fibre, inclusive blowing in {GLO}| market for | Alloc Rec, S was used.
The eco-‐costs for energy use to heat the building per 1 m2 of insulation with passive house thickness is calculated in the same way as the cost for heating the building, but in stead of using the cost of electricity, T, the eco-‐cost of electricity is used. The eco-‐cost of electricity can be obtained from the Ecoinvent V3 database and the medium voltage of the Swedish electric grid mix was used. This contribution turned out to be very small, approximately 0,2 € in total over the 50 years, due to that the eco-‐cost of electricity in Sweden was very low, only approximately 0,001 €/kWh. The average eco-‐cost of electricity in the world is approximately 0,012 €/kWh, which would resulting in a corresponding eco-‐cost of 2,4 €, 12 times more eco-‐costly than the Swedish electricity. This is probably due to a large proportion of the Swedish electricity production is produced by hydropower and nuclear power, which presumably give low eco-‐costs.
5.2 Economical cost
The economical cost of the three insulations consists of acquisition cost in year 0 and the transport and disposal in year 50. The currency exchange rate from SEK to € for all the calculations was taken the 2015-‐04-‐29 and was 9,25859879 SEK/€ (Google.se 2015).
5.2.1 Acquisition cost
The acquisition cost consists of the purchase price of the insulation, transport to the building site and cost of installation. The method of acquisition for rock wool and EPS are the same, but for cellulose fibre it differs. Rock wool and EPS are much more common on the insulation market, with big companies whose products can be found at building material retailers. For cellulose fibre it is different, it only takes up a small part of the market and could not be found at building material retailers. Instead you could order from the company directly and they would come to the building site and blow in the insulation, a kind of package deal3. When building a house you most likely do it through a contractor. They probably have agreements with material producers and could get similar package deals for rock wool and EPS also. But for this thesis the data that was available was used, see below.
5.2.1.1 Purchasing price
The purchasing prices of the insulations were obtained through market surveys on websites of building material retailers and through mail and/or phone conversations with the manufacturers.
35
The Paroc rock wool insulation price was obtained from Beijer Byggmaterials website. They had several thickness options of the insulation boards, so the cheapest option to obtain 35 cm thickness was calculated, which were three insulation boards of 120 mm, see table 4 for calculations. They were ≈11 €/m2 (including VAT) so ≈33 €/m2 for 36 cm thickness (Beijer Byggmaterial 2015). For simplicity 36 cm was used and not adjusted to 35 cm.
The Sundolitt EPS insulation price was obtained from bygghemma.se. The combination of three insulation boards with 100 mm thickness and one board with 50 mm thickness was the cheapest way to attain 35 cm thickness (Bygghemma.se 2015). The calculation can be seen in table 4. In the mail conversation with Emil Syrén at Sundolitt he stated that a price of about 64,8 € (600 SEK) per m3 would be reasonable, which would give 22,7 €/m2 for 35 cm thickness, a difference of 4,1 €/m2, but he suggested that the price found on Bygghemma.se should be used2. Table 4. Purchasing price for rock wool and EPS for 1 m2 of 36 and 35 cm thickness respectively (Beijer
Byggmaterial 2015, Bygghemma.se 2015).
Board thickness
Board price (incl. VAT)
Calculation Price for passive house thickness
Rock wool 120 mm 11 €/m2
€
3⋅ 11 33 €/m2
EPS 100 / 50 mm 7,5 / 4,4 €/m2
€
3⋅ 7,5 + 4,4 26,8 €/m2
The cost of Isocell cellulose fibre insulation was obtained through a phone interview with Andreas Östlund, VD/CEO at MBS AB3. Since the installation of cellulose fibre works differently than installation of rock wool and EPS, blown in versus boards, the price is in a package deal. The price for material, transport to building site and installation combined was 54 €/m3 (without VAT) for blown in cellulose fibre, resulting in
€
54⋅ 0,39⋅ 1,25 ≈ 27,4€/m2 (VAT included) for 39 cm thickness. This price was an estimate for a house when a private person bought cellulose fibre to be blown in. Divided up the cost breakdown is approximately 0,86 €/kg for the material and 0,38 €/kg for the blown in installation, transport included.
5.2.1.2 Transport to building site
For cellulose fibre the transport to the building site was included in the price. For rock wool and EPS it was calculated with the website budguiden.se, a site which gathers many logistics companies so you can search for the best price to transport your specified amount of cargo from A to B. The amount of rock wool or EPS needed for the walls of the house for passive house standard is
€
176⋅ 0,35 = 61,6 m3. Pallet dimensions were 2,4 x 1,2 x 1 m so 21,4≈22 pallets were needed. The weight was 100,8 kg/pallet for rock wool, and for simplicity it was assumed the price would be the same for EPS. The transport distance was set from Gothenburg to Lerum, approximately 21 km. The resulting 15 offers from different logistics companies were in the range of 67 € to 628 €, without VAT (Budguiden.se 2015). The cheapest ones did not have good reviews, the most expensive ones were to expensive to consider, so the cheapest option with good reviews was chosen to represent the transportation cost, which was 177 €, 221 € with VAT. Per cubic meter of insulation this would cost 3,6 €/m3, which can be compared to the transportation cost Emil Syrén2 at Sundolitt recommended for transportation of EPS which was 3,8 €/m3. So 3,6 €/m3 for
36
transportation is probably a good estimate. This gives a transportation cost to the building site of 1,26 €/m2 of for passive house thickness for rock wool and EPS.
5.2.1.3 Installation
For cellulose fibre the installation of the insulation was included in the price. For rock wool and EPS the cost of installation was calculated with Wikells Section Facts (Sectionsfacka) for new buildings from 2014-‐2015. Section Facts are data sets of the technical and economical aspects of the construction process from the building industry. Only the installation cost of rock wool was calculated. The installation cost of EPS is assumed to be the same as for rock wool since the installation process is similar. According to Section Facts it takes 0,09 hours to install 1 m2 of 120 mm rock wool insulation board. The salary is 20,3 €/hour with an additional overhead expense of 252 % of the salary. So the installation cost of rock wool/EPS is
€
0,09⋅ 20,3⋅ (1+ 2,52)⋅ 3 ≈19,3 €/m2 of 36 cm insulation thickness (Wikells byggberäkningar AB 2014).
Now the cheapest combination to reach 35 cm insulation was used without regards to the installation cost. It might be cheaper to use thicker but more expensive boards because the installation cost would compensate, but for simplicity this set up was used. Also, since the chosen combination of EPS boards to reach 35 cm was four boards, and for rock wool three, this calculation is not completely accurate for EPS, although probably a good estimate.
5.2.2 Disposal cost
The disposal cost was obtained from Renova Miljö AB, one of the leading companies in the disposal and recycling business in western Sweden (Renova.se 2015). The information was collected though a phone interview with the Renova costumer service6. Renova sets out a container at the building site and then collects it when full. It costs 65,2 € to set out a 16 m3 container at the building site. Every transport back and emptying cost 97,5 €. The cost per ton for handling is 136,4 € of combustible waste which goes to incineration and 147,9 € for incombustible waste which presumably goes to landfill.
So for the example passive house 61,6 m3 of rock wool or EPS is needed, which means the container will be filled up 4 times. So for rock wool, which only goes to landfill, the disposal cost in year 50 will be:
€
(4⋅ (65,2 + 97,5) +147,9⋅ 61,6⋅ 0,035)⋅ 0,3561,6⋅ (1+ 0,03)50
=1,26€/m2
The disposal cost for EPS is calculated in the same way, but now half goes to incineration and the density is 0,02 ton/m3 in stead of 0,035 ton/m3, so the cost amounts to 1,07 €/m2.
For cellulose fibre insulation, which needs
€
176⋅ 0,39 = 68,6 m3 of insulation for the example house, 5 containers are needed, although the fifth one is only one third full. All cellulose fibre goes to incineration and the calculation looks like this:
€
(5⋅ (65,2 + 97,5) +136,4⋅ 68,6⋅ 0,0465)⋅ 0,3968,6⋅ (1+ 0,03)50
=1,62€/m2
6 Renova Miljö AB costumer service, telephone interview 2015-04-28
37
5.2.3 Total economical cost
Summing up of the whole life costs in figure 11. The installation cost, which is the labour cost for installation, is a quite large part of the economical cost for rock wool and EPS, which cellulose fibre seems not to have because it is included in the package price. The package price for cellulose fibre includes purchasing price, transport to building site and labour cost for installation.
Figure 11. Proportions of the discounted economical costs for 1 m2 of insulation over 50 years with
passive house thickness.
5.3 Energy cost
The method used to calculate the energy cost in the 3E cost-‐C2C method assumes the building is heated with electricity, so this assumption is followed. Equation 1 is used:
Equation 1.
€
Cegn = K ⋅ T⋅ Nicηi
+Nvcηv
⎛
⎝ ⎜
⎞
⎠ ⎟ ⋅AapAew
There was no explanation for the K in the Silvestre et al. (2013) article. Instead 0,1 was just given. When calculating with this the results were not good, the energy cost became unrealistically small. After a mail conversation with José Dinis Silvestre7 he explained that
7 José Dinis Silvestre, Assistant Professor at the University of Lisbon, head author of the 3E cost-‐C2C article, mail conversation 2015-‐04-‐23
27 €
1 € 1 €
2 €
19 € 19 €
1 € 1 €
33 € 27 €
0
10
20
30
40
50
60
Rock Wool EPS Cellulose Fibre
Economical cost troughout the life cycle
Purchasing Prics (A1-‐A3)
Transport to Building Site (A4)
Installa�on (A5)
Disposal Cost (C and D)
Package Price (A1-‐A5)
38
the K represents the percentage of time of the year when the heating or cooling system is on in the building. 0,1 is the default value defined in the Portuguese Regulation of the Characteristics of Thermal Behaviour of Buildings (in Portuguese), 2006. He explained that this percentage varies depending on where you live and suggested that 0,6 might be a better estimate for Sweden. In a colder country the heating system needs to be on longer periods of the year than warmer countries. A K of 0,6 would mean that the heating system is on around the clock 7,2 months of the year. In June, Julie and August it is reasonable to assume that the heating does not need to be on, maybe September also. So that leaves 0,8 months of time which we can consider wiggle room, where it can be warm enough to not need heating before or after June to September. So K = 0,6 was used for the calculations. The K value will be discussed in short in chapter 9, future development.
The cost of 1 kWh of electricity for a Swedish household, T, may of course vary between suppliers and over time. But in general the cost for electricity with VAT and network charges included has been close to 1 SEK/kWh for a long time, so T was chosen to be 1 SEK/kWh, or 0,108 €/kWh. A calculation was made with data from Vattenfall, one of the major electricity suppliers on the Swedish market (Vattenfall.se 2015). There was data for the variable monthly electricity cost in kr/kWh for the years 2010 to April 2015, without energy tax, sales tax and distribution charges. The average electricity cost for 2014 to April 2015 was calculated, which was 0,35 kr/kWh. The energy tax for most households and companies is 0,294 kr/kWh and the sales tax on the energy tax is 25 %, resulting in a total tax of 0,3675 kr/kWh (Ekonomifakta 2015). The distribution charge in Gothenburg is 0,27 kr/kWh (Göteborg Energi 2015). Summing up these costs we see they add up to 0,35+0,3675+0,27 ≈ 0.988 kr/kWh, which is very close to 1 kr/kWh, confirming this choice. If we do the same for the years 2010 to April 2015 the average cost is 1,077 kr/kWh.
The nominal annual heating needs per square metre of net floor area of the house, Nic, was defined by the passive house certification criteria, which states that the space heating demand may not exceed 15 kWh/(m2•year) (International Passive House Association 2015). The nominal efficiency of the heating equipment,
€
ηi , is assumed to be 1 both for simplicity and because it is 1 in the Silvestre et al. (2013) article. The nominal efficiency of the cooling equipment,
€
ηv, is assumed to be 3 for the same reasons, although the nominal annual cooling needs, Nvc, is assumed to be 0 kWh/(m2•year), because this is Sweden… The net floor area of the house under assessment, Aap, is 152 m2 and the total area of the external wall being assessed, Aew, is 176 m2.
The energy cost from the use stage was then calculated for the next 50 years with the NPV formula, equation 2, and summed up, resulting in a cost of 21,6 €. This is the energy cost for all three insulations since their thicknesses make them thermally equivalent.
It is important to note that the calculated energy cost for the passive house is the maximum allowable energy used for heating according to the passive house standards. The point of a passive house is that it does not need to be heated except though body heat, sunlight and the electrical equipment in the building, such as computers, household appliances and ventilation (Passivhuscentrum.se 2015). These sources should contribute the 15 kWh/(m2•year). So basically the true cost for heating a passive house should be zero, and the calculated scenario above would be as if no electrical equipment was used except the heating system and no one lived in a the house, but the house still needed to maintain a comfortable temperature inside. Since all three insulations have the same energy cost the proportional result between the three would be the same.
39
5.4 Summing up costs
Summing up all the 3E cost for 1 m2 of insulation for passive house standard with an energy consumption of 15 kWh/(m2wall•year) we get the final result seen in figure 12.
Figure 12. Total 3E C2C costs for 1 m2 of insulation with the thermal resistance needed for passive
house standard in Sweden and a life span of 50 years and an energy consumption of 15 kWh/(m2wall•year).
As can be seen in figure 12 rock wool and EPS are exactly as costly, after being rounded of to the closest euro. Rock wools economical cost is a little larger but EPS environmental cost is three times as big as rock wools. Cellulose fibre is the cheapest by far, outperforming the other two by 31 €. This is due to being basically environmentally neutral since the fibre is made primarily from reused renewable materials and because the acquisition cost is much smaller then the other two insulations. The acquisition cost is cheaper and since it is a package deal with the transport and installation included the price. Although, there might be additional costs in the building process if there needs to be special adjustments to accommodate blown in installation, this has not been investigated. Also, since the cellulose fibre needs 39 cm thickness while the other two insulations need 35 cm thickness, there probably will be some extra costs for the materials and building process in the rest of the house. This has not been investigated either. If these additional costs are relatively small, and the supplied data is correct, the cellulose fibre seems like the preferred choice according to the 3E cost-‐C2C method.
A passive house should not use any energy for heating, so if the energy cost is considered zero, the total costs would instead be 58,2 € for rock wool and EPS and 27,3 € for cellulose
3 € 10 €
-‐ 2 €
55 € 48 €
29 €
22 € 22 €
22 €
-‐10.0€
.0€
10.0€
20.0€
30.0€
40.0€
50.0€
60.0€
70.0€
80.0€
90.0€
Rock Wool EPS Cellulose Fibre
Total 3E C2C cost for 1m2 of insuladon for passive house standard
Energy Costs
Economical Costs
Environmental Costs
40
fibre. So these numbers would be a more correct comparison to a regular house, but for simplicity the numbers in figure 7 will be the ones representing the passive house. So keep in mind that the passive house values would realistically probably be 21,6 € less. But, on the other hand, the labour costs of building a passive house compared to a regular house are much higher. The house needs to be airtight, every joint must be sealed, so the level of detail, expertise, precision needed to build a passive house is much higher (Passivhuscentrum.se 2015).
5.4.1 Regular new built minimum requirement standard house
With all this collected data already in Excel, only some additional data was needed to make the same calculation for a regular new built house, a house that follows the Swedish minimum standards. The minimum requirements for a new house are regulated in the Swedish National Board of Housings building regulations. In the Code of Statutes of the Swedish National Board of Housing, Building and Planning the maximum average heat transfer coefficient allowed is 0,4 W/m2K for all four climate zones in Sweden for a average house using electricity for heating (BBR 22, 2015). To adjust most of the data the heat transfer coefficient of 0,1 W/m2K for passive houses need to be changed to 0,4 W/m2K, so
for example, the insulation thickness of rock wool and EPS would be
€
35⋅ 0,10,4
= 8,75 cm.
This may sound thin, but the regulations are weak. Another example is the Dutch regulation which was updated in 2012 to an R-‐value of 3,5 m2K/W which would result in a thickness of
€
3,5⋅ 0,035 = 0,1225 =12,25cm for rock wool and EPS (Concept Bouwbesluit 2012). On the Swedish Energy Authority’s website there are recommendations for the U-‐value of the external wall for a renovated or new house from the Swedish National Board of Housings network BeBo (Byggherrarnas Beställarorganisation) (Energimyndigheten 2015). They recommend a U-‐value of 0,13 W/m2K, which would need 27 cm of rock wool or EPS. But for this calculation the regulations are used.
The environmental cost and acquisition cost can be adjusted the same way as the thickness. The disposal cost also, except that now only on container is needed. The energy cost is adjusted according to the Swedish National Board of Housings building regulations. The buildings specific energy consumption in climate zone IV, where the example house is located, is 50 kWh/m2 per year distributed over the liveable floor area, so Nic = 50 kWh/m2
(BBR 22, 2015). The results can be seen in figure 13.
41
Figure 13. Total 3E C2C costs for 1 m2 of insulation with the thermal resistance needed for a new
minimum requirement regular house in Sweden and a life span of 50 years and an energy consumption of 50 kWh/(m2wall•year).
Basically the environmental and economical cost is reduced to a third compared with the passive house and the energy cost becomes the largest expense by far. The energy cost alone becomes almost the same size as the total cost for passive house standard for rock wool and EPS. For cellulose fibre there is a much larger difference as the total cost is 49 € for passive house standard and 80 € with minimum standard house. For rock wool and EPS the total cost for 50 years is higher by approximately 8 € and for cellulose fibre by 31,5 €. For rock wool and EPS passive house standard pays of after 36 years and for cellulose fibre after only 12 years compared to the minimum standard new built house.
5.4.2 Average existing house
On the Swedish Energy Authority’s website where the data for the average existing Swedish house for the year 2013 was, there was also data for the heating energy consumption for the average house (Energimyndigheten 2015). The average Swedish house needs 12 200 kWh/year for heating. This can be used to calculate Nic, 12200/152 = 80,3 kWh/m2.
The K value in equation 1 is hard to understand even after an explanation from Silvestre. The problem with the K is that it supposedly is the proportion of time that the heating or cooling equipment is on. But the Nic = nominal annual heating needs per square metre of net floor area of the building (kWh/m2*year). So the total amount of energy used for heating is already in the formula. So if the total annual amount of energy used for heating is used for Nic, the constant should be 1 instead of 0,1 or 0,6. In the calculations made for the
1 € 3 € 0 €
15 € 13 € 8 €
72 € 72 €
72 €
.0€
10.0€
20.0€
30.0€
40.0€
50.0€
60.0€
70.0€
80.0€
90.0€
Rock Wool EPS Cellulose Fibre
Total 3E C2C cost for 1m2 of insuladon for a new minimum requirement house
Energy Costs
Economical Costs
Environmental Costs
42
passive house and the new built minimum standard house the maximum amount of energy for heating allowed was used, so here K = 0,6 would probably be a good estimate since the heating is not on all year round. But for the Swedish average existing house the Nic used is the total energy consumption, therefore the time when the heating is of is already accounted for, so the K should equal 1.
If we use this in equation 1 and calculate for 50 years the cost for energy would be 192,6 €/m2 of external wall, which is more than twice as much as the total cost for 1 m2 of the minimum standard wall. If the house would be renovated to passive house standard with rock wool or EPS and we assume it would cost the same as the installation in a new built house and we don’t use any of the old insulation, it would start paying back in less than 11 years. For cellulose fibre in less than 5 years. Of course there would be additional cost to rebuild the house to accommodate the extra insulation, but still, the payback time would probably not be long.
43
6 Results of method evaluation One of the goals with this thesis was to evaluate the 3E cost-‐C2C method, but a method to evaluate methods could not be found. Therefore the 3E cost-‐C2C method is compared to other methods used to evaluate and aid in the choosing of building materials. Also, personal reflections will be given of how it was to work with the 3E cost-‐C2C method in the discussion in chapter 7.
The first most obvious methods to compare the 3E cost-‐C2C method with are the individual parts of the 3E cost-‐C2C method. Using just the LCA or WLC methods or just using the energy cost calculation to decide which materials to use. Then other methods and variations will be discussed.
6.1 LCA
Just making an LCA of the optional materials would result in the most environmentally friendly option being the best choice, which in theory sounds good. If the functional unit is set to achieve a certain thermal performance, as it was in this thesis, then the energy consumption during the user phase is equal for all the options. But there are two major problems with using just the environmental performance to decide which material to use. The first obvious one is that the price of the product is almost always relevant. Usually the price is probably even one of the most important aspects, so using just LCA as basis for the decision is in most cases not realistic. What if one option performs slightly better environmentally, but it is twice the price? But of course, the environmental aspects could be considered together with the price of the product, but this leads to the second problem. The LCA (or EPD) results are presented in amounts of emissions and/or impact categories that can be hard to interpret. One option can be performing well in some of the impact categories but worse in others, whereas another option performs the opposite. Which on is then the most environmentally friendly one? That is why it can be beneficial to have a single indicator, such as the Eco-‐costs method, and suddenly something resembling the 3E cost-‐C2C method is being discussed.
6.2 WLC
If just the WLC method is used this would basically result in that the option with the cheapest purchasing price would be chosen. The transportation, installation and disposal cost seems to be similar between options, unless there is some kind of package deal as there was for cellulose fibre. Using just the WLC method would result in that a lot of other important aspects would be overlooked, like the environmental performance and energy usage during the user phase. As can be seen from the total 3E C2C cost for insulation for a minimum standard house over 50 years this option is more expensive in the long rung than for a passive house option, even if the purchasing price of the insulation is cheaper.
6.3 Energy cost calculation
Using just the energy cost calculation would not be relevant as it does not compare materials used, just the performance or thickness of them. Often houses are built and then sold, so the builder may not be so concerned with how much energy the house uses for heating.
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6.4 Project ‘Butterfly’
Project ‘Butterfly’ is a software tool created to calculate life cycle costs and the environmental impact of the components and design of both new building projects and before refurbishment of residential buildings (BLP Insurance 2015). Consultants companies and universities in the United Kingdom (UK) created it. ‘Butterfly’ is aligned with existing building industry processes and standards in the UK and it utilises the Life Cycle Costing tool. You can import information from CAD software or input into ‘Butterfly’ directly. It will enable users to compare components of every aspect of the home and capital costs can be compared with costs in use (BLP Insurance 2015). Environmentally speaking the focus is mainly on embodied carbon cost.
This method seems good, although it has not been tested for this thesis so a comparison of how it is to use cannot be made. The ‘Butterfly’ project is not yet completed but a work in progress. It did not say on their website, but you would probably have to pay for the software, whereas using the 3E cost-‐C2C method is free except for the time used. Also the software is made for the UK, so it would probably be complicated or impossible to apply for buildings outside of the UK. The idea seems good though; to have a software tool with a database to use for the calculations would simplify and speed up the calculation. Also, with the 3E cost-‐C2C method you have to assume how energy efficient the building will be. With the ‘Butterfly’ software and database, presumably you can get an indication of how energy efficient the building will be with certain material choices.
6.5 Variations of the 3E cost-‐C2C method
Variations of the 3E cost-‐C2C method are also conceivable, like not taking the whole life cycle into account. For example ignoring the end-‐of-‐life phase which is a relatively small part of the total cost, in part due to that discounting for 50 years result in the cost of the end-‐of-‐life phase being divided by
€
(1+ 0,03)50 ≈ 4,4 . But ignoring parts of the life cycle can lead to less reliable results, because before the whole life cycle has been examined we cannot know where there will be large costs.
Another variation could be discarding the environmental part and just focus on the energy and economical parts. As can be seen in the total cost diagrams, figure 12 and 13, the environmental cost is a relatively small part of the total cost, at least when it comes to insulation. But ignoring the environmental aspects seems both immoral and wrong because the environmental cost does have an affect, even if it might be small. The EPS would have been 6 € cheaper than rock wool in the passive house option if it had not been for the environmental cost, now EPS and rock wool are as expensive. Also, in the study of five wall constellations for apartments made in the Silvestre et al. (2013) article, the environmental cost was 23,2 % on average of the total cost (Silvestre et al. 2013). For the insulations in the passive house, figure 12, the average environmental cost is 5,5 % of the total cost. So it seems that insulations are quite environmentally friendly in proportion to other parts of walls, which sounds reasonable because insulations are not very material intensive, they have a low density compared to the other parts of a normal wall. So do not let the insulation results be an indicator of the proportion of the environmental cost, when making a calculation for a complete wall it is important to include all the costs.
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6.6 3 E factor
The 3 E factor method was developed in Lithuania (Rogoža et al. 2006). It is an optimisation method developed to minimize energy cost, environmental pollution and expenses during the life cycle of a single-‐family house. The environmental part consists of the CO2 emissions from the production of the insulation materials and from heating the building. The cost and energy used in the production of insulation, transport to building site, the cost of construction, renovation and heating of the building are taken into account. All three E aspects are weighted the same and then used to optimize the thermal insulation (Rogoža et al. 2006). This method is almost like a light version of the 3E cost-‐C2C method. It does not cover the whole C2C life cycle and it only looks at the carbon emissions and ignores other environmental factors.
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7 Discussion The fact that EPD data could be used to obtain the eco-‐cost was a great benefit and time saver for someone who wants to evaluate walls with the 3E cost-‐C2C method. Making a full LCA is time consuming and often hard if the companies producing the components are not very cooperative, which they often are not because it takes time for them to get the data and they do not want to reveal their trade secrets. Alternatively data from databases such as Ecoinvent could be used, but then it might not be representative of the materials under consideration. So using EPD data, which is a type of LCA that represents the products, is an appealing option.
One thing the 3E cost-‐C2C method does not cover is social accountability, such as workplace values, health and safety, freedom of association, discrimination, working hours and child labour. For the insulation examined in this thesis, which are produced in Europe, both EU and the individual countries should regulate this. But if building materials were produced in countries where the social accountability is more dubious this could be an important aspect not covered by the 3E cost-‐C2C method.
Also the method does not take the individual characteristics of the materials into account, like the fire class, resistance to moisture and compressive strength. These aspects would have to be considered together with the results of the 3E cost-‐C2C method.
Equation 1 is a bit confusing. It seems the energy cost for heating is only distributed over the external walls, which would mean the there is no energy loss through the roof or floor. It could be that the equation is only applicable to apartments, where the roofs and floors are adjacent to other apartments. This is not discussed in the Silvestre et al. (2013) article. Another problem with the energy cost calculation is that the formula does not take the insulating capabilities of the wall being analysed into consideration, but rather the whole building. The 3E cost-‐C2C method would be easier to apply to the design stage of a building if all the equipment affecting the thermal performance did not need to have been decided.
There is no monitoring of the results of the 3E cost-‐C2C method. On the other hand the method is mainly meant as a support tool when choosing what wall constellation to use. Probably no comparative walls can be monitored.
Although the 3E cost-‐C2C method is meant for walls, it might also work for other parts of the building that affect the thermal performance. For example the heating system, windows, doors or the roof. A different functional unit would probably be needed for the heating system, but the main principals of the method could probably still be applied. This has not been examined closer in this thesis.
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8 Conclusion In this chapter the research questions are answered and conclusions drawn.
A1. What are the major environmental impacts of rock wool, polystyrene and cellulose insulation though out their life cycles from C2C?
The environmental impacts of rock wool are relatively small, except the GWP, which is almost the same size as the GWP of EPS. EPS also has a large recourse depletion and relative the other two insulations also a large POCP. Cellulose fibre has a small environmental impact all together except for the GWP where there even is a positive environmental impact, a reduction of greenhouse gases in the atmosphere.
A2. What is the cost of the environmental impacts of rock wool, polystyrene and cellulose insulation though out their life cycles from C2C?
The environmental impact costs follow the proportions of the environmental impacts. EPS has almost three times the environmental cost of rock wool, see table 5. Cellulose fibre has a positive environmental impact. Generally the environmental cost is low compared to the total cost, and therefore do not affect the end result by much. For the regular minimum standard house the environmental cost is even lower, approximately 2,5 times lower than the environmental cost for passive house standard.
Table 5. Environmental costs and benefits and proportion of total cost for passive house and minimum standard house.
Rock Wool EPS Cellulose Fibre
Environmental Cost/Benefit, Passive House
3,5 € 9,8 € 1,7 € benefit
Percentage of total, Passive 4,4 % 12,2 % -‐3,4 %
Environmental Cost, minimum standard
1,5 € 3,0 € 0,2 €
Percentage of total, minimum 1,7 % 3,4 % 0,2 %
A3. What is the energy cost of rock wool, polystyrene and cellulose insulation during the use stage?
The energy cost over 50 years for all three insulations is 21,6 € per m2 with passive house standard thickness, since they are functionally equivalent, see table 6. Realistically though, the aim of a passive house is to have zero expenses for heating. For the new built Swedish minimum requirement house the energy cost is 72 € for all three insulations. The energy cost for an average existing house in Sweden over 50 years is 192,6 € per m2 of external wall.
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Table 6. Energy costs and proportions of total costs for passive house and minimum standard house.
Rock Wool EPS Cellulose Fibre
Energy Cost, Passive House 21,6 € 21,6 € 21,6 €
Percentage of total, Passive 27 % 27 % 44 %
Energy Cost, Minimum Standard
72 € 72 € 72 €
Percentage of total, Minimum 82 % 82 % 90 %
A4. What are the economical costs of rock wool, polystyrene and cellulose insulation though out their life cycles from C2C?
Summing up the economical costs for passive house standard reveals that this is the largest part of the total cost, see table 7. For a new built regular house that just meets the minimum standards the economical costs are approximately a forth of the economical costs for passive house standard, and a much smaller part of the total cost.
Table 7. Economical costs and proportions of total for passive house and minimum standard house.
Rock Wool EPS Cellulose Fibre
Economical Cost, Passive House
54,8 € 48,4 € 29,0 €
Percentage of total, Passive 68,6 % 60,7 % 59,2 %
Economical Cost, Minimum Standard
14,6 € 12,9 € 8,3 €
Percentage of total, Minimum 16,6 % 14,7 % 10,3 %
B1. Does the 3E cost-‐C2C method give a good indication of which insulation that performs best with regards to the environmental, energy and economical performance?
The results of which insulation performs best according the 3E cost-‐C2C are quite clear. The cellulose fibre is both more environmentally friendly and has a cheaper acquisition price, and thus has the cheapest total cost. Rock wool and EPS have an equal total cost.
B2. Should the environmental impacts be summarized into one value for easier comparisons or can this be problematic?
If the Eco-‐costs method is considered to be relatively accurate then there should be no major reason for concern about converting the environmental impact to a single indicator. For the 3E cost-‐C2C method it is imperative to be able to get a cost value from the environmental impacts so they can be compared with the other costs. But the Eco-‐costs method itself can be discussed. For example, there is no actual cost for the environmental
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impact; it is an external cost. You, as a buyer, are not forced to pay anything for the environmental cost whereas the economical and energy parts are actual costs. Had there been an enforced tax system based on the eco-‐cost it could be incorporated, but now the environmental part of the 3E cost-‐C2C method is basically based on good will. But on the other hand, you would not use the 3E cost-‐C2C method if you planed to ignore the environmental cost. Converting the environmental impacts to costs gives a good indication of how important the impacts are in proportion to the total cost.
B3. Are there other more suitable methods to compare building assemblies related to thermal performance?
The only other option that seems to cover almost as much of a building assembly’s life cycle and important aspects is Project ‘Butterfly’. But Project ‘Butterfly’ has not been examined properly for this thesis because the software tool is currently a work in progress, and when it is finished will probably cost money. Also it is made for the UK market, so how applicable it is worldwide is dubious. The 3E cost-‐C2C method covers almost all important aspects of a building assembly and gives a comprehensive overview of the costs that occur throughout the life cycle. The method has a good, easy to understand structure and feels logical. There are some drawbacks; the method does not cover social aspects, the amount of energy needed to heat the building per square meter of floor area is hard to know before the building is finished and quite a lot of data needs to be gathered and calculated. Using the 3E cost-‐C2C method is quite straightforward and easy once you understand it; it’s a logical method that feels mostly intuitive. It follows the relevant standards and covers all parts of the examined products life cycle steps.
A. Which one of rock wool, polystyrene and cellulose fibre insulation is the most suitable to use to reach the energy efficiency of a passive house, with regards to the environmental, energy and economical life cycle from cradle to cradle?
In conclusion we can see that cellulose fibre is the best option with regards to economics and the environment and that passive house standard pays of in the long run. Summing up the 3E costs for passive house standard we see that rock wool and EPS are equally expensive for 1 m2 of insulation, and that cellulose fibre is quite a lot cheaper, see table 8. For a new built regular house that just meets the minimum standards the total costs are higher due to the high energy cost.
Table 8. The total 3E C2C costs for 1 m2 of insulation and for the whole house of 176 m2 of outer wall with passive house thickness and minimum standard house thickness over 50 years.
Rock Wool EPS Cellulose Fibre
Passive House, 1 m2 79,9 € 79,8 € 48,9 €
Minimum Standard, 1 m2 88,1 € 87,9 € 80,4 €
Whole Passive House, 176 m2 14 058 € 14 042 € 8 614 €
Whole Minimum Standard House, 176 m2
15 505 € 15 476 € 14 155 €
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B. Is the 3E cost-‐C2C a suitable method to compare building assemblies related to thermal performance?
Yes, the 3E cost-‐C2C method gave good, clear results with regards to the 3E’s and was a logical tool to work with. As long there are EPDs for the materials the calculations should be relatively quick, but not all materials have an EPD. Then the calculation will be more complicated since an LCA is needed. The method is very general and encompasses all types of walls; different wall types and insulation thicknesses can be compared.
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9 Future development It would have been interesting to compare the eco-‐cost of a product obtained with EPD data with what the eco-‐cost would have been if an LCA was made specifically for the purpose. If the eco-‐costs were similar, using EPD data as a shortcut would be a good option, and if they differ a lot maybe not. This could be examined in a future study.
Project ‘Butterfly’ sounds like an interesting idea, and a combination of that kind of software, a database of construction materials and building techniques and the 3E cost-‐C2C method seems like an appealing option. Such a program would reduce the calculation time to a fraction of the time currently needed.
Another probably cheaper option could be to make a well-‐structured Excel sheet for the 3E cost-‐C2C method, where the input data (in the right format/functional unit) could be entered and all calculations made automatically. Then all you needed to do to make a calculation with the 3E cost-‐C2C method would be to gather the relevant data, adjust it to the functional unit and enter it into the Excel sheet. Depending on what is being examined the input data needed may vary. For comparing insulations, as in this thesis, the relevant data would be the EPD data (which includes density and thermal resistance of the insulation), purchasing price, transport to building cost, installation cost (or use the Wikells Section Facts as nominal values in the data sheet) and disposal cost. Also the values in the energy cost calculation formula need to be estimated. If an example house is already assumed and entered in the data sheet, like the one used in this thesis, the values needed would be the K-‐value, electricity cost and the nominal annual heating needs per square meter, the rest could be assumed values. When for example an entrepreneur is deciding what materials to use in a building some of this data is most likely already gathered, like the acquisition costs, and there is probably an annual heating needs target. So if there are EPD’s for the optional materials, a 3E cost-‐C2C calculation could probably be made quite fast with a prepared Excel sheet.
The K-‐value in the energy cost calculation could be explained better, so it would be easier to understand and estimate. Or standard values could be defined for different parts of the country, or the world. Experts on the subject could look at statistics over how large percentage of the year the heating system is on. Maybe there could be values defined for each of the climate zones used by the Swedish National Board of Housings. Or the actual value of the energy for heating could be used, as it was in the calculation for the average existing house in Sweden. This value has a rather large impact on the end result, especially if the building is not so well insulated. In conclusion, a better definition is needed.
Currently cellulose fibre is relatively small on the insulation market, rock wool and EPS together holds a majority. If the calculations made for this thesis are correct and represent the costs of the insulation, cellulose fibre should start taking larger proportions of the market. But there might be supply problems if to many people start using cellulose fibre, since it currently depends on recycled newspapers, which is a limited resource. But if this were to occur, cellulose fibre could be made of other organic fibres or new fibres, although then the 3E cost-‐C2C calculations would needed to be recalculated.
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10 References Scientific articles
Bare, J.C., Hofstetter, P., Pennington, D.W., Haes, H.A.U. de (2000) Midpoints versus endpoints: The sacrifices and benefits. Int. J. LCA 5, 319–326. doi:10.1007/BF02978665
Jelle, B.P. (2011) Traditional, State-of-the-art and future thermal building insulation materials and solutions – Properties, requirements and possibilities. Energy and buildings, Volume 43, Issue 10, 2549 – 2563.
Kowatsch, S. (2010) Mineral wool insulation binders. Phenolic Resins: A Century of Progress, 209-‐242
Myhre, G., D. Shindell, F.-‐M. Bréon, W. Collins, J. Fuglestvedt, J. Huang, D. Koch, J.-‐F. Lamarque, D. Lee, B. Mendoza, T. Nakajima, A. Robock, G. Stephens, T. Takemura and H. Zhang (2013) Anthropogenic and Natural Radiative Forcing. Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. [Stocker, T.F., D. Qin, G.-‐K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA
Papadopoulos, A.M. (2005) State of the art in thermal insulation materials and aims for future developments. Energy and Buildings, Volume 37, Issue 1, pp. 77-‐86.
Rogoža, A., Čiuprinskasb, K., Šiupšinskasb, G. (2006) The optimisation of energy systems by using 3e factor: the case studies. Journal of Civil Engineering andManagement 12 (1) 63–68.
Silvestre, J.D, Brito, J.d., Pinheiro, M.D. (2013) From the new European Standards to an environmental, energy and economic assessment of building assemblies from cradle-‐to-‐cradle (3E-‐C2C). Energy and Buildings (64) 199–208
Books
Baumann, H., Tillman, A-‐M. (2004) The Hitch Hiker’s Guide to LCA. Studentlitteratur, First edition, ISBN 91-‐44-‐02364-‐2
Laszlo, C. (2013) Business Strategies and Management for Sustainability, Berkshire Essentials, ISBN-‐13: 978-‐1614729648
Gluch P. (2014) Perspektiv på LCC (in Swedish) Report / Department of Civil and Environmental Engineering, Chalmers University of Technology
Vogtländer, J.G. (2014) A practical guide to LCA for students designers and business managers, Cradle-‐to-‐Grave and Cradle-‐to-‐Cradle. VSSD Third edition 2014, version 2015, ISBN 978-‐90-‐6562-‐253-‐2
Wikells byggberäkningar AB (2014) sektionsfakta NYB 14/15
McDonough, W. and Braungart, M. (2002) Cradle to Cradle: Remaking the Way We Make Things, ISBN 0-‐86547-‐587-‐3
Environmental Product Declarations (EPD)
EUMEPS (region Scandinavia) (2013) Expanded Polystyrene (EPS) Foam Insulation (without flame retardant, density 20 kg/m³) EPS 100, Institut Bauen und Umwelt e.V. (IBU), Declaration number: EPD-‐EPS-‐20130077-‐CBG1-‐EN
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ISOCELL GmbH (2014) Blown insulation made of cellulose fibre, Bau EPD GmbH, Declaration number: EPD-‐ISOCELL-‐2014-‐1-‐ECOINVEN
Paroc AB (2014) Paroc Insulation, product group with density <70 kg/m³, The Norwegian EPD Foundation, Declaration number: NEPD00265E
Rockwool Products (2009) Environmental Declaration ISO 14025, The Norwegian EPD Foundation, Declaration number: NEPD 131E
Master thesis reports:
Duijve, M. (2012) Comparative assessment of insulating materials on technical, environmental and health aspects for application in building renovation to the Passive house level.
Regulations
BBR 21, Boverkets författningssamling, BFS 2014:3 (chrome-‐extension://ecnphlgnajanjnkcmbpancdjoidceilk/https://rinfo.boverket.se/BBR/PDF/BFS2014-‐3-‐BBR-‐21.pdf)
BBR 22, Boverkets författningssamling, BFS 2015:3 (chrome-‐extension://ecnphlgnajanjnkcmbpancdjoidceilk/https://rinfo.boverket.se/BBR/PDF/BFS2015-‐3-‐BBR-‐22.pdf)
Concept Bouwbesluit 2012. (chrome-‐extension://ecnphlgnajanjnkcmbpancdjoidceilk/http://www.rijksoverheid.nl/bestanden/documenten-‐en-‐publicaties/besluiten/2014/12/19/concept-‐wijziging-‐bouwbesluit-‐2012/concept-‐wijziging-‐bouwbesluit-‐2012.pdf)
EN 15804 (2012) CEN, Sustainability of Construction Works – Environmental Product Declarations – Core Rules for the Product Category of Construction Products, Comité Européen de Normalisation, Brussels, Belgium.
Websites
Beijer Byggmaterial (purchase price of Paroc rock wool) http://www.beijerbygg.se/store/privat/byggmaterial/isolering/stenull/v%C3%A4ggskiva-‐tr%C3%A4-‐c450 Visited 2015-‐04-‐27
BLP Insurance, Project ‘Butterfly’ http://www.blpinsurance.com/added-‐services/butterfly/ Visited 2015-‐05-‐12
Budguiden.se http://www.budguiden.se/?gclid=CIvKsfWS88QCFYT2cgodJkQAOA 2015-‐04-‐27
Bygghemma.se (purchase price of Sundolitt EPS) http://www.bygghemma.se/utomhus/bygg/isolering/cellplast/cellplast-‐sundolitt-‐s80/p-‐216939-‐216944 Visited 2015-‐04-‐27
Ekonomifakta (taxes on electricity) http://www.ekonomifakta.se/sv/Fakta/Energi/Styrmedel/Konsumtionsskatter-‐pa-‐el/ 2015-‐05-‐07
ElectronicsTeacher.com: http://www.electronicsteacher.com/succeed-‐in-‐physical-‐science/heat-‐and-‐thermodynamics/thermal-‐insulation.php Visited 2015-‐03-‐31
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Energimyndigheten: http://www.energimyndigheten.se/Hushall/Din-‐uppvarmning/ Visited 2015-‐03-‐18
Google search for “euro to sek”: https://www.google.se/webhp?sourceid=chrome-‐instant&rlz=1C5ACMJ_enSE521SE522&ion=1&espv=2&ie=UTF-‐8#q=euro+to+sek Visited 2015-‐04-‐29
Göteborg Energi (distribution charge) http://www.goteborgenergi.se/Privat/Produkter_och_priser/Elnat/Elnatspriser/Elnatspriser_i_Goteborg_ Visited 2015-‐05-‐07
International Passive House Association: http://www.passivehouse-‐international.org/index.php?page_id=80 Visited 2015-‐03-‐05
Isocell website: http://www.isocell.at/de/produkte/products/d%C3%A4mmstoffe/cat_201/zellulosedaemmung/prod_202 Visited 2015-‐05-‐23
Miljöbyggsystems website: http://www.miljobyggsystem.se/produkter/isocell/isolering/cellulosaisolering/ Visited 2015-‐05-‐23
Parocs website (information about the rock wool and fire class): http://www.paroc.se/losningar-‐och-‐produkter/produkter/pages/universell-‐byggisolering/paroc-‐extra-‐ Visited 2015-‐04-‐27
Passivhuscentrums website: http://www.passivhuscentrum.se/om-‐passivhus/detta-‐ar-‐ett-‐passivhus Visited 2015-‐04-‐25
PE International Sustainability Performance: http://www.pe-‐international.com/topics/what-‐are-‐environmental-‐product-‐declarations/ Visited 2015-‐03-‐12
Renovas website: http://www.renova.se/ Visited 2015-‐04-‐28
Sundolitt Produktguide (2010) chrome-‐extension://ecnphlgnajanjnkcmbpancdjoidceilk/http://st.bygghemma.se/files/0086eb51-‐9e65-‐4e74-‐8e31-‐4807ee51dee2/produktguide%20sundolitt%20cellplast.pdf
Sundolitt website: http://www.sundolitt.se/sundolitt/om-‐eps Visited 2015-‐05-‐17
The International EPD® System: http://www.environdec.com/ Visited 2015-‐03-‐12
The Model of the Eco-‐costs / Value Ratio (EVR), Delft University of Technology: www.ecocostsvalue.com Visited 2015-‐03-‐18
Vapour resistances and μ-‐values, Build Desk: chrome-‐extension://ecnphlgnajanjnkcmbpancdjoidceilk/http://builddesk.co.uk/wp-‐content/uploads/2013/01/vapourResistances.pdf Visited 2015-‐05-‐25
Vattenfall website (electricity price) http://www.vattenfall.se/sv/rorligt-‐elpris-‐historik.htm Visited 2015-‐05-‐07
