Conclusions from the Scientific Committee for thermal ...cicenergigune.com/uploads/publicaciones/documentos/CUADERNO_in… · 1 Introduction 6 Conclusions from the Scientific Committee

Conclusions from theScientific Committee

for thermal energy storagemeetingS held on 14-15 deCember 2009 and 23 September 2010

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This paper summarises the conclusions reached during the first meeting of the scientific committee responsible for thermal ener-gy storage organised by CIC Energigune. This is an R&D centre that was recently set up as the result of the Basque Government’s invest ments and collaboration from various leading companies in the energy sector. The centre’s goal is to become a leading ins-titution for oriented basic research in the fields of electricity and heat storage, as well as in some types of renewable energy, thus creating knowledge and technology to underpin the important in-dustrial activity in the Basque Country. In order to carry out this research task it is absolutely essential, especially during the initial activities of CIC, to have a scientific committee for each area. Such a committee should be comprised of internationally renowned re-searchers who would provide CIC with their expertise and support in tasks such as the definition of research plans. Their contribution will be fundamental for mitigating the implicit risks of these kinds of projects in the long term.

Given that the area of thermal energy storage is given priority du-ring CIC’s start-up, the purpose of the first committee was to es-tablish an expert snapshot of the current situation and the existing context of opportunity. For this reason, an analysis was carried en-compassing the current situation, the challenges associated with each area (increase in the need for quality energy, environmental awareness and the boosting of renewable energies, increasing de-mand for investments associated with the generation and distribu-tion of power), the existing technology and the areas of opportuni-ty for CIC (research directed towards materials, interfaces). Taking into account the above, it was concluded that the CIC Energigune project presents a challenge that will not only provide research with added value but also with relevant competitive positioning in es-sential areas.

Conclusions from the Scientific Committeefor thermal energy storage

mEEtINGS hEld oN 14-15 dECEmbEr 2009 aNd 23 SEptEmbEr 2010

1. Introduction .................................................................................. / 6

1.1. CIC Energigune’s research activities

1.2. Origins and purpose of the scientific committee

1.3. Goals of the scientific committee meeting in December 2009.

2. Current situation and scenario in 2020 .......................................... / 8

2.1. Overview of energy demand: trends and initial conclusions

2.2. Solar power and thermal storage contributions

2.3. Thermal storage alternatives

2.4. Conclusions on thermal energy storage and development

3. Long-term challenges in the field of thermal storage ................... / 13

3.1. Main problems and challenges

3.2. Conclusions regarding challenges

4. Definition of interesting and potential research areas for CIC. CIC Energigune’s positioning ....................................................... / 14

5. Conclusions and next steps ......................................................... / 16

5.1. Conclusions

5.2. Next steps

6. Acknowledgments ...................................................................... / 18

7. Bibliography ................................................................................ / 18

8. List of participants ....................................................................... / 19

abstract

Introduction1

6 Conclusions from the Scientific Committeefor thermal energy storage

This paper is the first part of a series of papers that will describe the role that CIC Energigune plays within its lines of research regarding thermal energy storage. Its content is intended to summarise the main conclusions reached following the scientific committee meeting in this area held on 14-15th December 2009 and 23rd Sep-tember 2010.

As an introduction to the work of CIC Energigune, the scope of CIC itself must be placed in context, as well as that of the scientific committees associated with each of its areas of research.

1.1. CIC Energigune’s research activitiesCIC Energigune is an R&D centre that was recently crea-ted. Its prime objective is to promote basic and multi-disciplinary leading research based on collaboration in fields such as energy storage and renewable energy in order to underpin the important industrial fabric of the Basque Country.

The CIC Energigune Foundation is one of the CIC cen-tres that has already been created, or is in the process of being set up. They represent the spearhead of the research endeavour in various areas and have a gua-ranteed budget in keeping with such an endeavour, as well as the full commitment of their local area to boost research. The centre operates within the framework of long-term R&D plans approved recently as part of the considerable investment drive made primarily by the Basque Government.

The CIC Energigune laboratory will be focused on basic research aimed at achieving innovative results in various areas. This, in turn, will generate knowledge and deve-lop technology in the field of energy sources with me-dium and long-term excellence criteria to thus become an international expert in its field. In addition to the ge-neration of knowledge and technology, CIC’s mission also includes the following set of objectives:

• To support public institutions and industrial organi-sations, especially technological centres and asso-ciated universities, to create a working framework adapted to technology transfer based on the acqui-sition, generation and dissemination of advanced scientific and technological knowledge.

• To encourage Basque companies to share ideas with each other, thus striking a balance between their needs and research, development and innovation processes.

1.2. origins and purpose of the scientific committeeBased on the premise of developing a benchmark basic research activity in accordance with CIC’s operatio-nal model, the need to set up a scientific committee for each of its areas was identified. This committee is formed by internationally-renowned researchers who contribute their approach and knowledge regarding the following tasks:

• Support in drawing up the research plans for the next five years: future outlook, action areas, vali-dation of fundamental objectives, monitoring and biannual assessment.

• To establish a potential temporary collaboration with the research team to compare the most important milestones and to also act as a source of knowledge in the relevant research lines.

• To be a channel that helps the transmission of existing knowledge to the members of virtual CIC, the management of contacts and business oppor-tunities.

• To favour bidirectional collaboration mechanisms with organisations that could require the support of the CIC, and vice versa, by promoting the establish-ment of scientific collaboration and partnerships or joint ventures aimed, for example, at the creation of companies.

• To lend support in identifying profiles, and their sub-sequent assessment, during the selection processes for Project Leaders in the research area linked to each committee.

In short, the scientific committee aspires to be an orga-niser of research activity whilst at the same time trying to mitigate the risks that are implicit in a project with a long-term approach.

CIC has managed to involve internationally renowned researchers in the committees from different knowledge areas. Moreover, they reflect both an academic point of view and a more business-oriented perspective through which they guarantee heterogeneity and dynamism, both of which are decisive for its success.

Introduction

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1.3. Goals of the scientific committee meeting held in 2009 and 2010Since the thermal energy storage area is defined as a priority in CIC’s start-up and after having made com-parisons between the main benchmark companies, the meetings were convened with the following goals:

• To specify and verify the analysis concerning the cu-rrent situation of the technology and the existing areas of opportunity. This verification exercise, and the conclusions reached, will be used as relevant in-formation in order draw up the research plan for the area for the next five years. This work will identify key basic research directions and could provide the significant progress required to satisfy future requi-rements regarding the storage of electrical energy.

• To reinforce the interaction and participation of the committee members in the CIC as from these initial phases marked by rapid growth.

In the single working group, the methodological scheme pursued brought together committee members as well as various representatives from the virtual CIC (universities and technological centres) and from the business community directly related to the purpose of the research area (Sener, Technology Centers, etc.) thus enabling all of them to contribute their approaches and assessments.

The various workshops promoted interaction, which will not only strengthen CIC’s approach in future years, it will also serve to direct the rest of the R&D activi-ties and initiatives linked to the area of thermal energy storage.

The following pages summarise the main issues discus-sed during this scientific committee meeting, as well as the conclusions reached according to the agenda below:

• Assessment of the current situation and possible scenarios in 2020.

• Identification of long-term challenges regarding thermal storage.

• Definition of potential research areas.

• Conclusions reached by the scientific committee for thermal energy storage and next steps to be taken at CIC Energigune.

dr. manuel tello leónProfessor of Condensed Matter Physics, Universidad del País Vasco(www.ehu.es)

dr. Greg GlatzmaierHead of Advanced Heat-Transfer Fluids and Thermal-Storage Work at the NREL (National Renewable Energy Laboratory)(www.nrel.gov).

dr. rainer tammeHead of the “Thermal Process Technology” Department at the Institute of Technical Thermodynamics of the German Aerospace Center (DLR) in Stuttgart, Germany (www.dlr.de/Stuttgart)

dr. Eduardo ZarzaHead of the CSP Research Unit at PSA (Plataforma Solar de Almería), part of the Centre for Energy, Environment and Technological Research (CIEMAT).(www.psa.es)

dr. michael EpsteinHead of the solar plant research unit at the Weizmann Institute, Israel.(www.weizmann.ac.il/)

The committee members are as follows:

Current situation andscenario in 20202


2.1. overview of energy demand: trends and initial conclusionsIn order to establish priorities, draw up the action plans and reach conclusions, it was of paramount importance to initially gain an overview of the current situation. There are various milestones that should be taken into account as the base elements and these are summarised below:

a) Growth in world energy consumption over the next forty or fifty years,1 in spite of what happe-ned in 2009, points to a 50% increase around the world between 2005 and 2030: the total demand for energy in countries that are not members of the OECD will increase by 85% compared to an increase of 19% in OECD member countries.

b) There is a marked increased in environmental awareness reaching thresholds that are irreversible in terms of impact. This is already resulting in social and legal requirements aimed at cleaner energy sour-ces, with a lower percentage of emissions and higher efficiency levels: in short, a clear boost for renewable

energies that is reflected in the political agendas of leading governments.

c) There is a clear consensus regarding the balance and response to existing needs that can only be achieved via an energy mix in which the different generation sources complement each other to respond to a cy-clical and increasing demand.

Having reached this point, it is worth considering the main issues that are going to affect energy needs. Given that they are associated with the increase in con-sumption and with the limitation of existing resources (fossil fuels), they are forcing a change in the criterion used.

2.2. Solar power and thermal storage contributionsIn the aforementioned mix, solar energy is acquiring an increasingly important role, driven firstly by photo-voltaic technology and, more recently, by Concentrated Solar Power (hereinafter CSP). Next to wind power, solar power has become the renewable energy source with the most potential.

1 U.S. DOE (2008). See figure 52, “Growth in world electric power generation and total energy consumption, 1990-2030”.

Excelent Good Appropiate Inappropiate

Source: Protermosolar

Figure 1. CSP markets now and in the future

Current situation and scenario in 2020

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Four technologies are competing for the CSP plant market today: parabolic troughs, solar power towers, Stirling dishes and linear Fresnel reflectors. There are even different approaches to the same technology: for example, systems with several towers with small he-liostats, a single tower with large heliostats, parabolic troughs with thermal oil, direct steam generation con-centrators, etc. Because they are still at the bottom of the “learning curve”, it is impossible to say which tech-nologies will emerge victorious.

In relation to different decentralised generation systems, just like the distribution network provides energy where it is needed, the scenario for the future seems to de-mand storage systems that provide energy when it is needed.

Indeed, as storage allows linking variable generation with an equally variable demand, it is concluded that the storage systems will form part of the solution to the challenges put forward for various reasons.

a) adaptation to demand. Obviously, in a situation of variable generation, sys-

tems that allow adaptation to demand at any time are essential. Thermal Energy Storage (TES) allows energy from low peak times to be used during high peak times, when demand exceeds the amount that

can be generated at that moment. CSP plants with storage can take power to or from the storage whe-never necessary.

b) Greater capacity factor. A greater capacity factor allows increased use of

the Powerblock investment. Thermal energy storage allows more use of these blocks and results in a grea-ter annual capacity factor.

c) adaptation of deliverable electricity and out-put to needs.

Deliverable electricity and power production can be brought into line with building requirements. TES allows solar electricity to be dispatched after dark, and, “units are generated […] in which the power production rate can be adjusted or varied in accor-dance with financial or other conditions. Different generating units have different supply possibilities due to financial and technical reasons” (Arizona Pu-blic Service).

d) lower generating costs based on solar power. TES also lowers power generation costs based

on solar power due to the following reasons: it is cheaper than the additional cost per turbine; it allow generating systems to gain replacement capacity; and finally it can raise or lower the Le-vellised Cost of Energy (LCOE) depending on the

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Figure 2. Storage increases value

Source: Tom Mancini – Sandia National Lab.



THERMAL STORAGE

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Source: Tom Mancini - Sandia National Lab. National Renewable Lab.

solar field cost, thermal storage, field orientation (parabolic troughs) and distribution time rates. See figure 3.

From the foregoing it is concluded that thermal storage decouples energy collection and genera-tion, has high value because power production can match utility needs and is lower cost because sto-rage is cheaper than incremental turbine cost (see figure 4).

2.3.ThermalstoragealternativesDepending on the storage medium used, thermal energy can be classified as sensitive (sensitive heat is related to the energy that a material releases when its temperature drops or the energy that the material absorbs when it temperature increases), latent (latent heat is related to

Figure 3. Thermal storage also lowers cost

Source: Greg Kolb– Sandia National Lab.

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the phase change) or chemical (see figure). This third heat storage medium uses reversible endothermic che-mical reactions.

The thermal energy materials will be classified depen-ding on the storage media: materials stored through sensitive heat, materials stored through latent heat and materials stored through chemical heat.

The analysis of materials suitable to be used in thermal storage systems and their characteristics is underway and is one of the project milestones, along with a review of the technologies used for thermal energy storage des-cribed above.

Recently thermal energy storage was tested at high temperatures on a commercial scale at parabolic trough solar power plants Andasol 1 & 2.

2.4. Conclusions on thermal energy storage and developmentSeveral conclusions can be drawn from the foregoing:

• Thermal energy storage at high temperatures was tested recently on a commercial scale at parabolic trough solar power plants. Over the next two years it will be tested at the tower-based plant.

• Thermal storage is of capital importance for the development of the CSP industry. The various CSP technologies will determine the requirements or specifications that thermal storage research must fulfil. Current storage solutions are far from the “ideal” response to the needs of different technolo-gies. These solutions also have a long way to go to meet the ever-changing needs of the CSP sector.

• In any case, there is still no clear-winning technology in the CSP field. In fact there probably is no single technology that will emerge as the winner. Storage research should therefore establish synergies bet-ween the different technologies.

• The range of temperatures at which thermal sto-rage for CSP must be concentrated starts at 400 ºC, while in the field of thermal storage related to in-dustrial heat recovery this will range between 150-300 ºC.

• Thermal storage is currently based on molten ni-trate salt mixtures (approach with a relatively low energy density compared to phase change and thermochemical storage) or liquids that transmit and store heat which have a limited liquid tempe-rature range, which means they reduce the ther-modynamic conversion and stored energy density of power plants. In spite of thermal energy storage systems having existed on the market for decades, there are still essential gaps in understanding the processes which determine their operation, limita-tions and exploitation.

Classification of energy storage systems in relation to storage media

Source: Classification of energy storage systems according to media (Dinger, R. 2002), (Zalba, B. et.al 2003), (Van Berkel, J. 2005), (Lovgvok, K., et al 1999)

CUADERNO ingles-2011.indd 11 14/02/11 11:09



• Very few local and international groups are working in this field of research.

Therefore, the main conclusion regarding the des-cribed outlook is that this is an area with large scope, potential and applications but that the re-search team needs to be increased in accordance with the outlook and related challenges. These challenges need to be met through basic research, seeking radical and innovative evolution which,

through a qualitative and quantitative leap, will find solutions and develop new concepts that faci-litate closing the existing gaps and which likewise meet requirements detected for storage systems. The current situation of CSP technologies also re-quires the definition of lines of R&D that are com-pletely or almost independent from technology used in the solar field.

Long-term challenges in the field of thermal storage 3

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3.1. main problems and challengesHaving identified the current thermal storage outlook, some problems have been revealed which will represent major challenges that need to be solved. These challen-ges are described briefly below.

Available heat storage technologies these days suffer from insufficient energy densities and limited perfor-mance and reliability. They also still require extremely high investment levels. All of these problems stand in the way of more extensive use and market penetration in the industrial and power generation (solar) sectors.

The organic heat-transmitting liquid that is being used for parabolic troughs at power plants also has an upper temperature limit of 393 ºC. This is due to the ther-mal stability of the carbon-hydrogen bond, which we can assume applies to all organic liquids. Alternative inorganic liquids have good thermal stability at high temperatures (above 600 ºC), but their melting point is excessively low (between 100 - 220 ºC).

The main goal therefore lies in reducing the cost of in-vestment in commercial or pre-commercial storage sys-tems that already exist and looking for solutions that require less economic investment to provide thermal storage. Advanced storage solutions also need to be identified and developed with the potential for signifi-cant improvements in cutting-edge technology: deve-loping output through a broader range of operating temperatures (higher operating temperature and lower freezing temperature), storage with more energy den-sity and thermal conductivity and a reduction and con-trol of the expansion volume. Finally, improvements in terms of reliability are also necessary: duration, stability and decomposition of storage materials, and corrosion of components such as tanks, tubes, valves, etc.

There are therefore many challenges related to different solutions to improve the current situation:

• As far as sensitive heat is concerned more suitable liquid temperature ranges need to be achieved (low freezing point and high operating temperature), for instance, new liquids that remain liquid at ambient temperature and have good thermal stability above 400 ºC.

• Phase change materials need to be identified to im-prove conductivity and facilitate heat transfer, opti-mising its thermophysical properties.

• Thermochemical cycles could also be used, designed to exceed mass and heat transfer limits and increa-sing energy density.

3.2. Conclusions regarding challengesThere are several extremely important challenges as-sociated with high and medium-temperature thermal energy storage systems and it is difficult to predict when and where important progress is going to be made. These challenges have to be addressed through basic research by seeking radical and innovative evolution which, through a qualitative and quantitative leap, will lead to answers.

In accordance with CIC Energigune’s needs, current si-tuation and nature, the main points around which the centre’s research activity should revolve have been com-pared and established as the first step to identify the research areas that need to be developed:

• CIC Energigune, in its thermal energy storage area, must be a fundamental laboratory based on the re-search of materials. The aim of this is to try to com-plement the eagerness for research currently being shown by technological centres and to coordinate efforts with the university.

• The search for innovative progress must be on long-term basis, from 15 to 20 years. In order to have progressed for 2025, the work has to start now be-cause the development of new technologies requi-res a lot of time.

• A broad enough field of work is required to investi-gate and make progress. New ground needs to be broken in innovative areas which, in spite of having a high risk, have high return potential.

• Research must be directed towards real needs that require the acceptance of long-term risks in order for them to be satisfied.

• It is worth researching the materials in order to ulti-mately obtain systems. Cross-referenced knowledge is required to create a basis to later apply the breakthroughs to specific uses that have a real im-pact on the industrial sector. This is absolutely fun-damental when working on such a long-term basis: the acquisition of the basics provides flexibility and the capacity to react and avoids inflexibility and res-trictions.

• Work will be carried out flexibly and by adopting a culture that does not penalise failure or error but rather that defends the assumption of properly di-rected risks.

• International research is a goal, but due to the local nature of CIC’s mission, contact with the local indus-try and with the other partners involved in the Bas-que Science, Technology and Innovation Network must be considered.

• It is of paramount importance for the CIC to coor-dinate with other reference centres. Given that re-search challenges are so extensive, collaboration with other centres will be fundamental to reach an effective critical mass that strengthens dynamism and reduces the inflexibility of the research model.

• An effort needs to be made to combine modelling with experiments.

On a more specific level, the most important issues rela-ted to the research area are as follows:

• Better understanding and the improvement of mass and heat transfer limits in sensitive, latent and ther-mochemical heat storage systems will have a clear impact on storage systems for solar technologies.

• The increase of the operating temperature range will be sought.

• The use of characterisation and simulation/modelling will be essential to the different lines of research, as well as the synthesis of new and promising liquid formulae.

• Synergies will be required between the lines of re-search and groups to provide critical mass, assuming the importance of cooperation inside and outside CIC Energigune.

• The development of at least one line that could be directly reflected, through demonstration, on real application, which supplements lines of research with a long-term impact, will be of major impor-tance.

In terms of the solutions identified at present, sensi-tive/latent heat and thermochemical cycles, the re-search scope will include the following lines:

a) Sensitive heat (short and mid-term). Research will be focused on modelling, synthesis

and characterisation of new fluids that remain liquid at ambient temperature and have a good thermal stability above 400 ºC.

The use of aggregates that interact with the fluid should be considered, i.e. adding particles to inor-ganic liquids to try to lower their melting point. This method could use nanoparticles. Therefore, synthe-sis and characterisation of the nanoparticles will be essential to this work.

Finally, ionic liquids should be researched.

b) latent heat, phase change materials (mid-term). Firstly, the focus must be on the encapsulation of

phase change materials for thermal energy storage aimed at reducing the size and cost of TES system due to the high energy density of phase changes compared to sensitive heat capacity.

Secondly, the heat transfer concepts for latent heat storage must be improved, identifying, modelling and synthesising new liquids to transfer and store it

Definition of interesting andpotential research areas for CIC.CIC Energigune’s positioning4


with the new improved thermophysical properties, based on basic research aimed at developing these new types of liquids.

Finally, the potential of a second heat-transmitting liquid needs to be developed.

c) thermochemical reactions (long-term). Energy storage density needs to be increased through

thermochemical cycles based on redox reactions with pure solid oxides to improve thermodynamics and kinetics.

Modelling and experiments need to be combined to research limits in reaction rates and thermal power related with mass transfer. Materials and reversible reactions for thermochemical storage also need to be investigated.

d) New liquids. “New liquids” need to be developed with improved

thermophysical properties and a higher operating temperature (versus the use of oil or molten salt). Liquids with a mixture of several components could also be researched, with an eutectic composition

that has a lower melting point. This could include the thermodynamic modelling of eutectic formu-lae to predict compositions with the ideal melting points and the synthesis of the most promising li-quid formulae.

e) design. In the design section, storage though molten salt

needs to be improved: it must be more profitable and reliable.

Research activities and topics should be divided accor-ding to specific risks, time frame and technical matu-rity to combine R&D activities with a shorter time frame and an equally low risk and activities with a longer time frame and high risk. Also, considering the expected size of the storage department which will have around 30 members (in a period of 3-5 years), no more than three different research topics should be dealt with in order to have a specific critical mass for each of them. The activities must also be flexible in terms of temperature ranges and must be targeted at parabolic troughs and solar power towers.

definition of interesting and potential research areas for CIC.CIC Energigune’s positioning

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5.1. Conclusions• The thermal energy storage and medium and high-

temperature storage areas have tremendous poten-tial and, moreover, are coherent with the consensual view of the future characterised by the increase in generation using renewable energies, climate change and the development of technologies and industries with a high added value.

• There are currently various technologies planned on a long-term basis, however all of them present cha-llenges which will have to be addressed.

• When focussing on the aforementioned lines of re-search, activities with a shorter time frame, which are important to improve existing CSP technology and contribute to industry demand, need to be combined with longer-term R&D concepts with a higher risk that have the potential to provide a profi-table and reliable TES solution in around 5-10 years.

• This research will have to direct itself towards trans-verse elements that allow developing knowledge regarding materials, mass and heat transfer and thermochemical cycles which ultimately facilitate the search for solutions to the problems identified in the different existing applications.

• To achieve a specific critical mass, the TES de-partment must focus on few activities or research topics and not try to cover every TES area.

• Partnerships need to be set up with a leading CPS research institute in Spain —preferably without ac-tive TES R&D activities— to have access to know-how on CSP systems, as well as to create and lead a TES network at local research institutes —mainly in the Basque Country— to integrate their storage knowledge and activities.

• Key scientists should contribute their own ideas and views, but these must be adapted to the range of R&D topics and areas that the CIC Energigune Ma-nagement and the thermal energy storage scientific committee have identified.

In short, the CIC was founded in its thermal energy sto-rage area with a clear focus and the capacity for action and guidance. There is consensus on the interest and attractiveness of the project and of the very interesting challenge that lies ahead.

As well as these general themes, the following specific conclusions can be drawn in relation to the lines of re-search that CIC Energigune must cover:

• The area of research that needs to be covered in the short term is storage using molten salt. R&D

activities must be focused on problems with mate-rials or design problems.

• The overall aim should be provide a more profita-ble solution than the technology available now. The laboratory equipment and test facilities must be in addition to the Spanish research institutes’ R&D in-frastructures.

• In the long term, the areas of research should cover “new liquids”, new materials and conceptual design for latent or thermochemical storage.

5.2. Next stepsDue to starting from zero and because the main aim is to set up an international benchmark research group specialising in heat storage at high temperatures, very specific guidelines need to be established.

Considering the current situation of CIC Energigune’s thermal energy storage area, the primary goal for the next five years should be realistic. In other words, it will be a major challenge that will require tremendous effort to take on the commitment to turn CIC, with an exce-llent reputation, into the leading group in Spain and the main point of contact for the Spanish high temperature storage industry.

To fulfil this goal, the following matters need to be ad-dressed.

a) Diversifying the lines of research excessively is not recommended. It would be better to focus on two or three areas. As mentioned above, the approach taken in the different areas, as well as the enginee-ring and material aspects, will depend on the scien-tific preferences and background of the key people in charge of the thermal storage area. In accordance with the challenges and lines of research considered in the scientific committee’s conclusions, to under-take the research activity the following will be ne-cessary:

• An overview of the most avant-garde breakthroughs.

• Detailed information on R&D activities being un-dertaken around the world.

• The identification of important activities that have not yet been covered or solved properly by other groups.

• Information to avoid reproducing well-known or established activities.

• Definition of specific criteria to evaluate the suc-cess and scientific quality of the thermal energy storage department, for example, number of

Conclusions and next steps5


scientific articles, number of presentations at important conferences, percentage of external funding, and so on.

b) There will have to be a research leader with knowledge of basic research. He will have to know how to manage human teams and equip-ment. It will also be essential for him to be able to coordinate efforts, identify needs and seek synergies and leverage with the activities per-formed made by third parties. He is the critical element of the project and his selection will de-pend, to a large extent, on the success of the CIC in its line of research for thermal storage. By going into more detail in this aspect, emphasis is placed on three facts that could be important when finding the right person: challenges attract young people provided that they are not limited and they are able to develop their own work. The creation of the CIC Energigune is a unique opportunity since the starting point is zero and good researchers allow their curiosity to get the better of them.

c) A centre with these characteristics must be able to have sufficient resources and excellent inter-national equipment both to facilitate the deve-lopment of the research carried out in the CIC (physical and virtual) and in order to add value to the centre with regard to attracting talent. Ins-truments will be necessary to measure thermal conductivity, heat capacity, melting point, den-sity and viscosity of the new liquids depending

on the temperature. A laboratory with the ca-pacity and equipment to completely characterise the storage material surfaces is also required. This laboratory will have instruments to mea-sure the area and morphology and the changes in these characteristics can be recorded because the storage system loads and unloads through a number of thermal cycles. The development of simulation and modelling tools for materials, hardware and software, will be critical for redu-cing research times and defining the fields of study.

d) It will be fundamental to make constant com-parisons and to have a very active “antenna” function, since one of the most important functions of the CIC Energigune will be the re-compilation of information, not only of a scienti-fic nature, but also commercial and information on technologies developed by other companies, something which is difficult since it is usually confidential.

e) All of the partners involved in this R&D field in the Basque Country must be efficiently coordina-ted to avoid duplicating efforts and wasting va-luable resources. A priority action recommended for CIC Energigune, in conjunction with other partners in thermal storage R&D activities in the Basque Country, is definition of a procedure to ensure the right synergies that complement each other in every R&D activity and program regarding thermal energy storage at CSP plants.

Conclusions and next steps

17

Acknowledgments

Bibliografhy

6

7


The team at the CIC Energigune would like to extend their thanks to the committee members, not only for their participation but also for their commitment to the project and the enthusiasm shown.

The participation of the members of the board has also been fundamental, and we are grateful to them for it. They have contributed their vision of the needs of the market which is essential for ultimately steering the analysis towards a pragmatic focus.

• Informe SItuacIón de la InduStrIa. (protermosolar, 2009).

• InformeS anualeS de SandIa natIonal lab (EEUU), (2009, 2010).

• Informe anual de natIonal renewable lab (EEUU), (2009).

• claSSIfIcatIon of energy Storage SyStemS accordIng to medIa (Dinger, R. 2002), (Zalba, B. et all 2003), (Van Berkel, J. 2005), (Lovgvok, K., et all 1999).

• offIce of baSIc energy ScIenceS, department of energy (2007). Basic research needs for elec-trical energy storage, Office of Basic Energy Sciences, Department of Energy, July 2007.

• red eléctrIca de eSpaña: <http://www.ree.es>.

• U.S.DOE(2008). International Energy Outlook 2008 (IEO2008). Report number: DOE/EIA-0484(2008). Release date: April 2005.

• dInçer, I. and roSen, m.a., “Thermal energy storage, systems and applications”, John Wiley & Sons Ltd., Chichester, England, 2002.

• PilkingtonSolarInternacional,GmbH, “Survey of thermal storage for parabolic trough power plants”, National Renewable Energy Laboratory, Toledo OH, USA, 2000.

• Hermann, U., geyer, m. & Kearney, d., “Overview on thermal storage systems”, FLABEG Solar International GmbH, 2006.

• Zalba, b., marIn, J.m., cabeZa, l.F. and meHlIng, h., “Review on thermal energy storage with phase change: materials, heat transfer analysis and applications”, Applied Thermal En-gineering, vol. 23, no. 3, pp 251-283, 2003.

• tamme, r., “Phase-change storage systems”, Workshop on Thermal Storage for Trough Power Systems, Golden CO, USA, 2003.

List of participants 8

19

NamE INStItUtIoN

Dr. Eduardo Zarza Head of CSP research unit at PSA (Plataforma Solar de Almería), part of the Centre for Energy, Environ-ment and Technological Research (CIEMAT).

Dr. Manuel Tello León Professor of Condensed Matter Physics, Universidad del País Vasco (www.ehu.es)

Dr. Rainer Tamme Head of the «Thermal Process Technology» De-partment at the Institute of Technical Thermody-namics of the German Aerospace Center (DLR) in Stuttgart, Germany

Dr. Greg Glatzmaier Head of Advanced Heat-Transfer Fluids and Ther-mal-Storage Work at the NREL (National Renewable Energy Laboratory) (www.nrel.gov)

Dr. Michael Epstein Head of the solar plant research unit at the Weiz-mann Institute, Israel

Mr. Jesús María Goiri CIC Energigune CEO

Mr. José Manuel Castellanos CIC Energigune Corporate Development Director

Mr. Juan Ignacio Burgaleta Technology Director Torresol Energy - SENER

Ms. Ana Aranzabe Manufacturing Processes Director TEKNIKER-IK4

Ms. Mª Isabel Arriortua Head of Research General Services. Mineralogy and Petrology Department - UPV-EHU

Ms. Virginia Madina Surface Ingenieering Inasmet - Tecnalia

Mr. José Ignacio Hormaeche CEO Ente Vasco de la Energía

Ms. Cristina Oyón Technology Innovation Director SPRI

Parque Tecnológicoc/ Albert Einstein, 48

Edificio CIC 01510 Miñano, Álava

T. +34 945.297.108www.cicenergigune.com

Documents

Conclusions from the Scientific Committee for thermal ...cicenergigune.com/uploads/publicaciones/documentos/CUADERNO_in… · 1 Introduction 6 Conclusions from the Scientific Committee