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1
System Optimization for Cost Savings
of
“Integrated Geoexchange Systems”
By Chris Mitchell I.E.T. C.G.D.
Director, Geoexchange Technology
CleanEnergy
2
What’s in a Name?
• Heat pumps
• Geothermal heat pumps
• Ground source heat pumps
• Ground coupled heat pumps
• Geothermal GEO (earth) THERMAL (heat)
• Water source heat pumps
• Geoexchange
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3
What the Heck is a Heat Pump?
• A device that collects energy into a volume of
refrigerant in the form of low grade heat, it then
mechanically compresses that refrigerant
• Compressing something will increase its
temperature
• This temperature is now usable
4
What is Geoexchange?
5
Types of Heat Pumps
• Water to water units
• Water to forced air units
• Rooftop units
• Consoles
• Vertical stack units
• Vertical & Horizontal forced air units
• Low profile horizontal units
• DX units
• Reverse chiller units
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Sizes can range from ½ nominal ton to 400 nominal tons
6
How to Collect Heat
• Polyethylene pipe is buried into the ground inside which is an antifreeze
• The liquid in the pipe is kept at a lower temperature than the ground by the
heat pump invoking the second law of thermodynamics‘
• The amount of pipe is determined by the soil conditions and the load conditions
of the building.
• The amount of flow through the pipe along with the size of the pipe determines
how turbulent the flow is in the pipe.
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7
Where does the heat come from?
• Contrary to popular belief Geoexchange systems are solar collector systems
• The energy comes from the Sun
• The ground is the energy storage system
• The ground stabilizes the temperature so that it is usable
8
It’s Not Magic, It’s Thermodynamics
• First Law of thermodynamics states
that energy can be transformed
(changed from one form to another),
but cannot be created or destroyed.
• Second Law of thermodynamics
states that you need work to do the
heat transfer and that energy will
travel from hot to cold . You can not
stop this process but you can speed
it up or slow it down
9
10
Unlike Fossil Fuel Systems, there is:
Benefits of Ground Source Heat Pumps
11
Benefits of Ground Source Heat Pumps
12
Benefits of Ground Source Heat Pumps
13
Benefits of Ground Source Heat Pumps
14
Reduce Roof Penetrations & Clutter on the Roof
• Increase lifespan of
equipment
•Reduction in Maintenance
•Reduction in Mechanical
room size
•Reductions in roof
penetrations
15
Coefficient of performance – COP
BTU output/BTU input
Energy Efficiency Ratio - EER
BTU output/KW input
16
Efficiency/Coefficient of Performance (C.O.P)
17
All Heat Pumps are NOT Created Equal
• Check the EWT that the unit is designed to work at
• Check to ensure the piping is insulated inside the unit
• Check the voltage that the unit is designed for
• Is the unit ISO 13256 rated for ground loops
• Different heat exchanger technologies
• Different compressor technologies and qualities
18
Meeting that Spec
• HR and HE (Heat of Extraction & Heat
of Rejection)
• Outputs HC, TC, watch SC (Heat
Capacity, Total Cooling, Sensible
Cooling)
• COP (Coefficient of Performance)
• Electrical
• Physical size
19
• If the COP is different than the
ground loop, it must be resized
• If the ground loop is not resized
the loop will be too small for the
heat pump load
Spiral Effect
20
The Three Leg Stool
1. Design calculations
(load calc and ground loop sizing)
2. Heat pump selection
3. Delivery system
21
Accuracy of Load Calculations
• The loads are the foundation
• Incorrect building loads
= incorrect heat pump
= insufficient heating/ cooling of
building
= insufficient ground loop
= insufficient delivery system
22
“Rule of Thumb”
Do Not
use Rules of Thumb
Do not useheat loss
sizing ground loops
selecting heat pumps or
sizing ductwork
23
Amazing Sidewalk Art
(A minute away from heat pumps)
24
25
Finding that sweet spot
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26
Types of Ground Loops
Horizontal
Lake/Pond
Vertical
27
Large Lake Loop
28
Horizontal or Vertical?
• How much earth needs to be excavated?
• Lot size is usually a major qualifier
• Locations of property lines
• Locations of other utilities
• Distances from mechanical rooms
When properly sized for capacity, a
horizontal or vertical HX will perform
comparably. Operating costs will be similar
29
Thermal Conductivity (TC) Testing
• One TC test is required for every 30,000 sq ft of building space
• Test must be run for a minimum of 48 Hrs
• Results will obtain, undisturbed ground temperature, Thermal
conductivity, diffusivity of the soil, and moisture content
30
Why Antifreeze?
• C448 requires freeze protection to 9°F (5°C) below the minimal
expected loop temperature
• The heat-transfer fluid shall provide freeze protection to at least 9°F(5
Celsius) below the minimum loop-design temperature.
• Any antifreeze is acceptable as long as it conforms with CSA 448 ,the
manufacture of the equipment and local codes and regulations
• Potassium Acetate is banned in Canada
31
Pump! How Big?
• Design the piping system with the appropriate antifreeze
• Design and install the ground loop with the least amount of pressure
drop
• Use a reverse return with equal lengths and distances within 10%
• Use an antifreeze that will keep the pumping costs down
• Keep your header to less than 8 circuits per header or sub header
32
Ground Loop Header Design
A. Pressure drop
B. Flushing velocity
C. Reynolds numbers
Influenced by:
Loop length, pipe size, GPM, antifreeze, number of circuits
1. Simple Flushing
2. Operational Pressure drop and flow
33
Pump Efficiency
34
Traditional Fin Tube Baseboard
35
Panel Radiators
36
Panel Radiators
37
Hydronic Heat Emitters
38
Geoexchange Hydronic Piping Configurations
39
40
Multiple Water Temperature Distribution System:
41
What is lift?
• Lift is the temperature difference from the source to the load
• The smaller the lift the more efficient the system
• Maximum load side temperatures of 130 F (preferred 110F)
Know your equipment capabilities
42
Water-to-Water Heat Pumps: Lift
43
• (A minute away from heatpumps)
Amazing Sidewalk Art
44
VFD Pumps (Variable Frequency Drive)
45
VFD Pump Curves
Proper pump modulation
46
Two Ways to Pump
47
• Single ECM
Circulators & zone
Valves on each heat
pump
48
Staging and VFD Control
Proper pump modulation and staging = reduced cycle times
49
Optimizing the Design
• Use all the features of geoexchange to your
advantage
• Increase COP
• Simultaneous heating and cooling
50
Water-water heat pumps withreversing valves
Water-to-Water Systems
Heat pump
Mass Tank
Pool heating90°F
Cooling off
COP: 4.2
51
52
Water-to-water heat
pumps without reversing valves
Water-to-Water Systems
Heat pump
Pool heating on
Cooling off110°F
45°F
COP: 3.2
Heat from earth loop is used to heat pool
or domestic hot water
53
Heating &
cooling – Units
with reversing
valves
Water-to-Water Systems
Earth loop
Valves switched to direct hot or chilled fluid to air handlers or fan coils
110°F45°F
60°F
Heating capacity: 257.6 MBHCooling capacity: 171.4 MBH
Electrical demand: 28.3 kW
System COP: 4.44
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54
Heating & cooling
– Units without
reversing valves
Water-to-Water Systems
Simultaneous heating
and cooling greatly
increases system COP
Earth loop
110°F45°F
Heating capacity: 224.4 MBHCooling capacity: 171.4 MBH
Electrical demand: 15.8 kW
System COP: 7.34
55
Passive cooling
with earth loop
Water-to-Water Systems
45°F
Cooling capacity: dependent on flow rate and
earth loop temperature
Electrical demand: dependent on pump
horsepower
System COP: 12-20
Valves and
piping allow the
loop fluid to be
circulated directly
through the air
handlers or fan
coil units if
temperatures are
appropriate for
direct cooling.
60°F
Earth loop
56
Using alternate
heat sources
Water-to-Water Systems
20°F
Ice Storage
110°F
With heat pumps designed for efficient low temperature operation the system makes ice for tomorrow’s cooling while heating the building overnight.
Heating capacity: 92.8 MBHIce making cap.: 67.4 MBH
Electrical demand: 7.5 kW
System COP: 6.3Earth loop
57
RETROFIT - Who Says it Can’t be Done
• Use existing air handling equipment
• Use existing furnaces
• Use existing rooftop units
• Use a redundant system design
• Use parkade MUA units as a dry cooler
Boilers:
• Ensure they operate as a heatpump
• Watch your return temperatures
• First stage second stage system
58
Existing air handlers in mechanical room
Who Says it Can’t be Done
Space to add heat/cool coil to
existing air handlers
Hydronic heating first stage, gas second
stage on an existing rooftop
59
Economics of a Good Design and Things to Consider for System Cost Reductions
• Fees paid for Qualified engineers and consultants can easily pay for
themselves
• Competitive first cost
• Minimize operational costs
60
Find Other Sources of Energy to Collect from
• Ice machines
• Coolers and freezers
• Ice rinks / pools
• Exhaust systems
• Drain lines and sewer lines
Reducing Costs of a Design
61
• Hybrid can enhance project economics
• Building Load balancing
• Can have a large reduction in first cost
• Reduction in maintenance cost
• Designed strategically not for redundancy!!!
Hybrid Approach
62
Consider all Loop Options
• Horizontal or lake loops can be an option to
reducing costs
63
• (A minute away from heatpumps)
Amazing Sidewalk Art
64
Avoid the Breaking up of a Project
• One contractor responsible for all disciplines:
– Design
– Installation
• Drilling
• Grouting
• HP Equipment Supply
• Header Tie in
• Antifreeze
Will reduce Costs, and reduce Risk
65
• All aspects of a geoexchange system must be properly managed from
design to installation and supply of equipment
Design Factors
66
Thermal Conductivity Test
• Can reduce the cost of a bore field
67
Deal with Ventilation Properly
• Energy recovery reduce peak and total loads reducing heat pump
requirement and ground loop size
68
Delivery System Options
69
Simultaneous Heating and Cooling
Simultaneous Heating and
Cooling will increase system
COP and can reduce costs
70
Impact of Ground Loop Design Temperatures on Installation Cost
• Good Design Drives Economics
• Don’t add safety factor on safety factor
71
Be Creative in Locating Heat Pumps
• Distributed heat pumps can reduce costs
– Shortest distance to the ground is usually the cheapest method of installation)
• Two pipe vs Four pipe
72
Your Designer must Fully Understand
• How a heat pump interacts with:
– Building loads
– Ground loops
– Distribution systems
– System temperatures
– Pumping requirements
– Antifreeze requirements
– Ventilation requirements
73
Reduce Dependency on Volatile Fossil Fuels
74
Levelized Cost of Energy Comparison
GHP the lowest Cost of energy
75
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77
Integration of Boilers / Co-gen units / Solar
Examples of Innovative Applications
78
Cooling a green house and storing
the energy
Case Study: Energy Recovery from a Greenhouse
79
• Industrial
Energy
Recovery
• Reduction in
Cooling tower
size
• Reduction in
run time
• Reduction in
HVAC
equipment
• No roof
penetrations
80
Making the ice and heating the building
Case Study: Ice Rink Application
81
Case Study – Copper Ridge Bigway Foods
• Copper Ridge Bigway Foods in
Whitehorse, Yukon is a community
grocery store
“This system has really impressed us. This store
operates around 70% less than our other stores.
-Sam Jurowich, Owner of Copper Ridge Food
StoreSOLUTIONS
CUSTOMER PERSPECTIVE
RESULTS
COMPANY OVERVIEW
• CleanEnergy™ designed an innovative system that is made up of seven heat pumps, a secondary loop that collects the heat rejected from the compressors on the refrigeration units and freezers, a boiler and an air handler– The rejected heat from the refrigeration
and coolers is then used to warm the building and provide hot water
– The small boiler is used to provide back up heat for those very cold days in the height of winter
• The building achieved a rating from Natural Resources Canada’s Commercial Building Incentive Program of 31.5 % higher than the Model National Energy Code for Buildings, which itself is 25 % better than the standard building code
82
Case Study – Curve Condo
OPPORTUNITY
• The Curve Condo decided to go with geoexchange to reduce operating costs and provide a green solution
• The Curve Condo is an eight
storey new condo being build in
Toronto, Ontario
PROJECT OVERVIEW
• CleanEnergy™ provided the
drilling and ground loop tie-in for
this project
SOLUTIONS
Lowering the drill rig into the pit
Drilling
83
Case Study – Planet Traveler
• The geoexchange system alone accounted
for 70% of their 80% reduction from
business as usual carbon emissions
“Geoexchange is the lowest hanging fruit on the
energy tree… You get more return for your
dollar than any other form of alternative
energy.”-Tom Rand, developer of Planet Traveler
SOLUTIONS
CUSTOMER PERSPECTIVE
RESULTS
COMPANY OVERVIEW
• CleanEnergy™ was instrumental in
providing the equipment, drilling and
installing the ground loop
• Planet Traveler, located in Toronto,
Ontario is “The Greenest Hotel in North
America”
84
Case Study – Keith’s GMC
• Keith GMC dealership in Okotoks,
Alberta
SOLUTIONS
RESULTSCOMPANY OVERVIEW
• To reduce their carbon footprint and operating costs, geoexchange and solar thermal panels were installed
• CleanEnergy’s dealer, React Energy, installed the vertical, closed loop system
• The owners have listed that the geoexchange system has lowered their energy consumption during heating cycles by 25-50%, and cooling by 25-30%
85
• Haldimand Motors is the largest
used car dealership in North
America
I’m very, very pleased. The cost of running the
building is very reasonable and CleanEnergy’s
geoexchange system is going to really benefit us.
- John Edelman, Owner, Haldimand Motors
Case Study – Haldimand Motors
SOLUTIONS
OPPORTUNITY
CUSTOMER PERSPECTIVE
RESULTS
COMPANY OVERVIEW
• Geoexchange has provided Haldimand
Motors with heating in the winter and air
conditioning in the summer
• CleanEnergy engineered the 40 ton
geoexchange system, supplied the
equipment, and installed the
horizontal ground loop in the field
behind the new building
• A new 64 bay shop was built and
incorporated geoexchange
86
Case Study – WestJet Calgary Campus
• The new campus was designed to
meet the LEED® Gold standard
“Our geoexchange system was a key technology in
qualifying our Calgary Campus for LEED®
gold. Geoexchange has also allowed WestJet to reduce
its greenhouse gas footprint by 1,250 tonnes per year.”
Sean Durfy, Past President & CEO, WestJet
OPPORTUNITY
CUSTOMER PERSPECTIVE
RESULTS
• WestJet benefited from geoexchange –
both on its bottom line and its carbon
footprint
– 35% energy consumption reduction
COMPANY OVERVIEW
• WestJet’s new campus in Calgary, Alberta
87
Case Study - Senior Complex
• Hearthstone By the Lake is a senior complex located in Burlington, Ontario
“The system has been up and running for 6
years, we are very pleased with operating
costs and comfort. Costs are right around the
expected cost to be”
- David Shotlander Hearthstone By the LakeSOLUTIONS
CUSTOMER PERSPECTIVECOMPANY OVERVIEW
• CleanEnergy™ provided the heat
pump application
88
Case Study – InVue Condominium
• This cruise ship inspired 14-storey condominium is located in Kelowna, BC
SOLUTIONSCOMPANY OVERVIEW
• Domestic hot water preheating is provided from the heat pumps
• Each suite has its own fancoils for individual heating and air conditioning
• CleanEnergy™ engineered the ground loop and interior mechanical system
– Open loop geoexchange system
89
RECENTLY COMPLETED PROJECTS
Milton Sports Centre, Milton, ONContract Value: $299,000; Completed Q1, 2011
Grant Harvey Arena, Fredericton, NB Contract Value: $1.0 MM ; Completed Q1, 2011
Johnson Pool, Cambridge, ONContract Value: $430,000; Completed Q4, 2010
Helen Gorman School, Central Okanagan, BCContract Value: $595,000; Completed Q1, 2011
Bridgetown Curling Club, Bridgetown, NSContract Value: $178,000; Completed Q4, 2010
89
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CURRENT GEOEXCHANGE PROJECTS
Mental Health Centre, Penetanguishene, ONContract Value: $1.46MM
South Okanagan Secondary School,
Oliver BCContract Value:
$131,000
Calgary International Airport - International FacilitiesContract Value: $4.4MM
MHCP Drilling
90
Central Nova Scotia Civic Centre, Truro, NSContract Value: $2MM Truro, Drilling
91
COAST TO COAST PROVIDER
91
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93
Know the True Cost of Geoexchange!
Thank You
www.cleanenergy.ca