GeoExchange TM Systems Using Natural Gas

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1 GeoExchange TM Systems Using Natural Gas 2 nd National GeoExchange TM Business & Policy Forum Geneviève Gauthier, Eng., M.S. December 11, 2007

2 AGENDA Natural Gas Industry & Energy Efficiency Energy efficiency programs and technologies GeoExchange TM Systems Natural Gas Heat Pump Characteristics Performance and operation Environment and CO 2 emissions Economical analysis GeoExchange TM and Natural Gas Technical challenges Non-technical challenges Concluding Remarks

NGTC: Who We Are Founded in 1992, NGTC is a

through performing contracts OUR MISSION To carry out

research development technology transfer projects

3 NGTC: Who We Are Founded in 1992, NGTC is a not-for-profit organization NGTC is entirely financed through performing contracts OUR MISSION To carry out in partnership with the natural gas industry: applied research development technology transfer projects thereby contributing to the improvement of our clients competitiveness.

4 Natural Gas Industry & Energy Efficiency Programs and Technologies Natural Gas Utilities & Energy Efficiency Financial incentives for high-efficiency appliances Demand Side Management (DSM) programs R&D financing for more efficient technologies Energy tips published on websites, bill inserts Gas utilities are interested in offering «green options» to their customers by including hybrid renewable/gas technologies to their portfolio * Annual Fuel Utilization Efficiency, ** Energy Factor

5 Natural Gas Industry & GeoExchange TM Systems GeoExchange TM Systems Canadian gas utilities are noticing the emergence of geothermal projects on their franchise Different policies/strategies are adopted by different utilities There is no consensus on how the natural gas industry should/could be involved (climate-dependent) Possibilities of Integrating Natural Gas to GeoExchange Water-loop heating system (alternative presented by some utilities) Back-up for conventional electric GeoExchange TM systems Natural-gas absorption heat pumps

ROBUR GAHP-W and GAHP-W LB ROBUR Introduced in early 2007 on the North American market (together with air-source models) Only commercial geothermal absorption heat pumps in N-A

6 ROBUR GAHP-W and GAHP-W LB ROBUR Introduced in early 2007 on the North American market (together with air-source models) Only commercial geothermal absorption heat pumps in N-A Several thousand absorption heat pumps installed worldwide, a few hundred geothermal applications The absorption cycle has been optimized for better performance in multiple scenarios

7 What is it? Energy source Cycle Absorption Natural gas Generation (natural gas) Condensation Evaporation Absorption Vapour Compression Electricity Condensation Expansion Evaporation Compression (electricity) Simplified Absorption Cycle Simplified Vapour Compression Cycle

8 Chemical vs. Mechanical Compression Simplified Vapour Compression Cycle

9 Chemical vs. Mechanical Compression Simplified Absorption Cycle

10 Refrigerant and Environment Refrigerant Absorption Ammonia Vapour Compression R410A, R407C, R22, and others Refrigerants R410A (HFC): no ozone depletion potential, GWP*=1,890 R407C (HFC): no ozone depletion potential, GWP=1,610 R22 (HCFC): ODP** = 0.05, GWP=1,700 Ammonia has no ozone depletion nor global warming potential *GWP: Global warming potential, GWP CO2 = 1.0; **ODP: Ozone depleting potential, ODP R12 = 1.0

11 Operating Temperature Gas Absorption vs. Compression Heat Pump Higher achievable temperatures: DHW production capability Temperature lift is higher in heating Absorption 1 Heating mode, source temperature = -1 o C (30 o F) Vapour Compression 2 Outlet max. water temperature T, at outlet max. temperature 65 o C (149 o F) 15 o C (27 o F) 54 o C (130 o F) 6 o C (10 o F) Cooling mode, source temperature = 25 o C (77 o F) Outlet min. water temperature T, at outlet min. temperature 1. ROBUR GAHP-W LB 2. Climate Master GSW120 3 o C (37 o F) 5 o C (9 o F) 4 o C (39 o F) 6 o C (11 o F) * DHW: Domestic hot water

12 Performance and Geothermal Well Temperature Gas Absorption vs. Compression Heat Pump Steady performance throughout a wide range of temperatures The trend is similar in cooling mode 4.0 Heating COP of absorption and vapour compression heat pumps COP H (compression), G.U.E. (absorption) Vapour compression heat pump Absorption heat pump Evaporator inlet temperature ( o C)

13 Discussion on the Efficiency Although COP and GUE coefficients correspond to the «real» efficiency seen by the end-user, to fairly compare electric and absorption heat pumps, one should take into account: Power generation efficiency Transmission losses, etc. For instance, when electricity is generated by natural gas power plants (example, may vary from one location to another): Power plant efficiency = approx. 35% Transmission losses = approx. 5%* COP = 3.5 (listed COP) x 35% x 95% = 1.2 When taking into account how electricity is being produced, the disparity between electric and natural gas heat pump efficiency is narrowed * Several references stipulate numbers varying from 5 to 25%

14 CO 2 Emissions Emissions per MJ delivered by an electric heat pump (gco2eq/mj) Coal Electric HPs Emissions vs Electricity Source* Based on 2004 emissions data from Environment Canada Doesn't include transmission losses 50.8 Refined petroleum products Less emissions produced by NG heat pumps than electric heat pumps 41.5 Natural gas power plant 0.0 Hydro / Nuclear Emissions per MJ delivered by a natural gas heat pump (gco2eq/mj) * Hypothesis: COP(electric) = 3.5, GUE (absorption) = 1.3

15 Global Energy Picture Even for provinces such as British Columbia, Québec, and Manitoba where the main energy source is hydroelectricity, «green electricity» not used locally could be exported to other Canadian provinces or American states where it could displaced fossil fuel-based electricity There is a lack of readily available tool to estimate how natural gas heat pumps could be compared to electric heat pumps considering the global Canadian (and North American) energy picture

16 Initial Investment Cost Gas Absorption vs. Compression Heat Pump Ground heat exchanger is smaller and cheaper From 10% to 50% (may be crucial, especially for commercial and light industrial sector) Extracts less heat from the ground than electric heat pumps Heat pump unit purchasing cost is higher Could be from 40 to 65% more expensive Additional cost depends on design heating and cooling load For commercial and light industrial applications, the need for expensive transformers or back-up systems could be avoided Total investment cost is usually cheaper Total investment cost is 5 to 40% less expensive Drilling cost is higher than unit cost

17 Energy Cost Gas Absorption vs. Compression Heat Pump Energy cost may be lower or higher, depending on Utility rates Climate (influence heat pump efficiency) Heating and cooling loads

18 GeoExchange TM and Natural Gas Technical Challenges Integration to Canadian buildings How to best integrate the absorption heat pump to HVAC/DHW geothermal systems? When does it compare advantageously to traditional heat pumps? Heating/cooling degree-days and design load, utility rates Training Required Certified plumbers Engineers/architects No Residential Heat Pump The only commercially available product in N-A targets large and multifamily residential, commercial, and light industrial facilities Heating capacity = 35.0 kw (120 MBH) Cooling capacity = 13.5 kw (3.8 tons)

19 GeoExchange TM and Natural Gas Non-Technical Challenges Market Maturity Lack of competition to stimulate the market Currently more expensive than traditional heat pumps, although total installation cost (including geothermal wells) is lower Lack of Visibility Low technology awareness Not mentioned in governmental energy efficiency programs Not covered by Canadian standards/norms Efficiency Programs/Grants Electric GeoExchange TM projects are heavily financed Governmental agencies and electric utilities offer grants Gas utilities still don t routinely finance GeoExchange TM projects

20 Absorption Natural Gas Heat Pump First Case Study in Canada Benny Farm Project 24-unit building located in a Montréal neighbourhood Equivalent of five 165-m wells (550 ft) Three (3) Robur GAHP-W heat pumps Provide heat for space heating and domestic hot water Occupation of the building is eminent Annual Energy Efficiency NGTC is measuring the heat pump efficiency for a 1-year period Building is heated, but there is no DHW consumption (no tenants) To date, G.U.E. > 130%

21 Summary Pros/Cons of the Technology When Compared to Traditional Heat Pumps + Higher achievable temperatures: DHW production capability + Steady performance throughout a wide range of temperatures + Lower drilling costs - Lower COP - More expensive - Know-how is not efficiently spread ± Life cycle cost ± CO 2 emissions

22 Concluding Remarks How could the natural gas industry further help the deployment of GeoExchange TM systems? 1. Favour the use of absorption heat pumps when it is: «Greener» and economically viable «Greener», but not economically viable, through financial incentives by appropriate authorities Not locally «greener», in the context where the electricity displaced by the use of natural gas heat pumps could be exported to areas where the electricity is generated by more polluting sources (power plants)

23 Concluding Remarks How could the natural gas industry further help the deployment of GeoExchange TM Systems? 2. Make electric GeoExchange TM Systems economically more attractive by reducing associated drilling costs Initial expenditure associated to geothermal wells may be excessive when the heating load is high (electric heat pumps) Electric GeoExchange TM Systems could be sized to meet the cooling load, and high-efficiency condensing furnace could shave peak heating hours Reduction in cost is imparted to the lower heat exchange area required

24 QUESTIONS? Geneviève Gauthier, Eng., M.S. Project Engineer (450) Stéphane Brunet, Eng., M.Sc. General Manager (450)

25 Heating and Cooling Performances Gas Absorption vs. Compression Heat Pump Lower performance (not considering power generation efficiency) Higher heating/cooling ratio: extra heat is available (DHW) Minimal performance required 1 Typical value Heating/cooling capacity ratio Absorption n/a G.U.E. H = G.U.E. C = Vapour Compression COP H =2.5 COP C =3.1 COP H =3.5 COP C = Federal regulations authorized by the Energy Efficiency Act 2. COP (Coefficient of performance): COP H/C = Heat produced (or extracted)/energy supplied 3. G.U.E. (gas utilization efficiency): G.U.E. = Heat produced (or extracted)/gas supplied * DHW: Domestic hot water

26 Economic Analysis Gas Absorption vs. Compression Heat Pump There is a lack of detailed case studies and economical analyses comparing the true cost of GeoExchange TM Systems using absorption heat pumps to those using compression heat pumps The following table compares the hypothetical life cycle analysis of residential GeoExchange TM Systems located in Vancouver, Edmonton and Montréal No absorption residential heat pump currently exists on the market The ratio of drilling cost/unit cost is inaccurate for larger installations; the cost of the unit(s) should be lower than the drilling cost It is expected that the life cycle cost would be even more favourable to absorption technology for multi-residential and commercial applications

27 Economic Analysis Life Cycle Cost (20 years) Doesn t take into account grants Absorption heat pump is economically viable in heating mode Doesn t take into account DHW production It is expected that the savings would be even greater with DHW Absorption Compression Space heating and cooling* Vancouver $19,200 $13,100 Edmonton $21,000 $35,300 Montréal $19,300 $18,600 Space heating only (adapted by NGTC) Vancouver $15,900 $12,600 Edmonton $20,100 $35,000 Montréal $15,200 $18,000 Diff. + $6,100 - $14,300 + $700 + $3,300 - $14,900 - $2,800 *M Kummert, M Bernier, A Costa, and J Paris, A comparison between geothermal absorption and compression heat pumps for space conditioning, International Journal of Environmental Studies, October 2007

GLOBAL WARMING IMPACTS OF GROUND-SOURCE HEAT PUMPS COMPARED TO OTHER HEATING AND COOLING SYSTEMS

- 1 - GLOBAL WARMING IMPACTS OF GROUND-SOURCE HEAT PUMPS COMPARED TO OTHER HEATING AND COOLING SYSTEMS Doug Cane, Principal and Brian Crossman, Associate, Caneta Research Inc.,Mississauga, Ontario, Canada