Micro-Cogeneration: Is There a KW in Your Future?

Transcription

1 Micro-Cogeneration: Is There a KW in Your Future? Skip Hayden Renewable and Integrated Energy Systems Better Buildings by Design 2010 Burlington, February 2010 Natural Resources Canada Ressources naturelles Canada

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3 Integrated Energy Systems

4 Objectives Appreciate what micro-cogeneration is Understand the range of advanced microcogeneration technologies now impending on the North American marketplace Understand the potential energy, environmental and system advantages offered by micro-cogeneration See how you may have your own kw in your future.

5 ?? What are you looking for????

6 CCHT: Canadian Centre for Housing Technologies

7 CCHT Research Houses Located in Ottawa and operated by three agencies NRCan, NRC & CMHC Consists of two identical research houses and townhouse-type infodemo centre Houses Design Heat Loss > 40,000 BTU/hr Both houses are under Simulated Occupancy Protocol

8 Microgeneration A notion of generation both heat and power on site to serve the thermal load <50kW th and electrical <30kW el plus the grid May employ any combination of electrical generation and storage technologies that are on or off grid Technologies Stirling Engines, IC Engines, Fuel cells, microturbines, thermophotovoltaics, thermoelectrics, solar or combinations of the above

9 Micro-Cogen Concept

10 Benchmark Architecture (natural gas fueled, outdoor unit, current technology) Inputs: electricity from grid weather inputs Intelligent Home Load management Outputs: normal AC loads space heating occupancy inputs Inverter / Charger Battery DC Bus: AC Bus: grid parallel domestic hot water space cooling managed AC loads fuel IC engine + 3 way catalyst Variable Speed DC output Shaft driven heat pump Hydronic Interface Cogeneration System radiant floor heat pool heat distilled water (?)

11 Why Microgeneration? Latest Advances in Building Technologies Security of Power Supply Control Over Assets Economics Reduce need for new power generation facilities Reduce GHG s

12 Potential functions / specifications Occasional Stand-By Service : Drawn from battery storage for a couple of hours max during occasional grid interruptions Supplies managed loads such as refrigerator, freezer, well pumps, controls, alarms etc Availability of about 1000 hours over 10 years Competes with the idea of buying a gasoline generator Can recharge during night at lowest grid rates (Ontario model) Peak Rate Avoidance & Emergency Service : Drawn from engine during daily peak electricity pricing period (Ontario model) Supplies heating / cooling needs, domestic hot water and selected loads Availability of 4 to 6 hours x 5 days per week resulting in 13,000 hours over 10 years Satisfies need for independence and preserves occupant comfort during emergencies Theoretical potential to zero out electricity bill Continuous Cogeneration Service Stirling engines and fuel cells will run longer at lower capacity with higher inherent E/Q ratios May need electricity storage even more than the IC engine option above Non-reciprocating systems promise longer life with lower maintenance Off-Grid Luxury Service Architecture suitable for integration of solar- PV / wind and solar- thermal Propane or Bio-diesel capability for luxury market segment

13 Myths, Facts and Customer Mindset Myths: Grid interconnection is a must (it s doubtful customers will invest their own money to put electricity on the grid) High electrical efficiency is a must (E/Q ratio is more significant) 500 $/Kw must be attained (< 10 Kw it s irrelevant, it s the up front incremental cost premium and monthly charges relative to other alternatives that counts domestic cogeneration systems compete for disposable income like any other consumer purchase) Facts: Reliability, low maintenance, low noise and low emissions are very important Customer Mindset: It s an appliance - integrated products are essential We are surveying how Canadian customers value each function independence ; comfort ; value and image may sell

14 Microgeneration Technology Options PEM and SOFC Fuel Cells Stirling Engines Reciprocating Engines Thermophotovoltaics Thermoelectric others

15 Proton Exchange Membrane (PEM) Fuel Cells Modulating output Efficiency 35-45% Pure H2 or external reformer Field trials around the globe

16 Solid Oxide Fuel Cell (SOFC) Output 1-50 kw electric Internal reforming Efficiency 45-50%

17 Solid Oxide Fuel Cell Trial Fuel cell operated for over 2 months. Operating period covered mid-winter conditions (outdoor temperatures for a few days in the range of 10C to 20C) Shoulder season conditions Spring 2005 Summer conditions several days with no space heating. Fuel Cell was in good operating condition throughout the project, and on its return. Fuel Cell demo project was successful as it met the objectives of the project.

18 Electrical Wiring

19 Power Generation and Load Satisfied Test House Electricity Consumption and Supplies (Excluding Data Acqisition and Heat Dissipation) 20-Mar Fuel Cell Electricity supplied to House Fuel Cell Electricity Exported to Grid Utility Electricity supplied to House CCHT Test House Consumption 2 Power (kw) 1 0 0:00 2:00 4:00 6:00 8:00 10:00 12:00 14:00 16:00 18:00 20:00 22:00 0: Time

20 Stirling Engine External combustor Close to mass production Electric efficiency 10-25% Large field trials in Europe Seen as a replacement of heaters and boilers (& Central Generating Plant)

21 External Combustor Cogeneration Stirling Engine Gaseous or Liquid (bio) Fuels AC, and DC backbone Generates heat and electricity Optimize BOP Alternative renewable energy sources

22 EnMax Pilot Calgary, December 2007 AC WhisperGen generating 1kW, propane fired Provided both heat and DHW to the home this winter Integrated with radiant floor heating through a Latento TM latent heat exchange thermal storage tank

23 Stirling Engine MicroCogen System with Electrical Storage Demonstrating combination system integration (forced air space heat and DHW) Investigating performance advantage of lithium-ion vs lead-acid batteries Exploring economics and environmental impacts using typical house electrical and thermal profiles

24 Stirling Engine Trials 6 kw (~20,000 BTU/hour) heat generated 750W electrical generated; 575W useable on the grid 115kg; 400mm x 550mm x 850mm Startup time before core reaches 70 C ranges from 0-30 min, depending on setup. The shortest uses no cooling water until core is at 60 C Shutdown time is mins. Shortest uses fresh cooling water and dumps the heated cooling water. Since startup and shutdown times are long, it is most efficient to run the engine continuously.

25 Stirling Engine Efficiency

26 IC engines Proven technology Integration with forced air and water based heating systems Electrical output 1-6 kwelect Large field trials in Japan

27 Hybrid IC Sngle-Cylinder Engine HE Condensing Furnace System Generate 1kW electric & 3.25/18kW thermal power (only heat condensing) 50% of generated electricity was used to satisfy the house demand; the rest was exported to the grid Operated reliably and with high efficiency at CCHT for 4 weeks Second generation under development modulating output and back up power + space/water heating Extremely quiet

28 Hybrid ICE/HE Furnace System CCHT Results Cost of Heating System Operation Breakdown of Electrical Supply and Demand Climate Energy System High Efficiency Furnace Two Stage Furnace Locked to High Outdoor Temperature Exported Electricity Oct Oct Nov Nov Dec Dec Dec Jan Jan Feb Feb Mar Mar Apr Apr Oct Oct Nov Nov Dec Dec Dec Jan Jan Feb Feb Mar Mar Apr-06 Date and Time Daily Heating System Cost of Operation ($/day) Average Dailiy Outdoor Temeprature ( C) 22-Apr-06 From Engine From Grid House Electrical Demand Electricity (kwh/day) 5 0 Date and Time

29 IC Micro-Cogen Aisin 6 Kw electric at 35% efficiency 10:1 turndown Low NOx Outdoor installation Very long maintenance interval

30 Borehole Storage to Manage Excess Heat

31 Micro-Cogen Integration Micro-cogeneration technologies to supply space and water heating requirements, along with electricity at overall efficiencies of 90% This potentially large (several million) distributed source would be a highly efficient way to reduce requirements for new large electricity generation with at least a 3-fold reduction in carbon emissions Further coupling this with cost-effective borehole storage for heat and later extraction with a heat pump could further double the emissions reduction Advanced, interactive smart controls are required to ensure optimally efficient energy generation and utilization within the residence and the grid This is an important step on the road towards net-zero housing

32 PHEV (Plug-in Hybrid Electric Vehicle integrated with house, micro-cogen and grid Micro-cogen system charging PHEV at night Driving green and efficiently during day Micro-cogen unit PHEV feeding electricity back to grid during peak A/C demand

33 Seasonal Storage for Excess Heat with Micro-turbine

34 Thermophotovoltaics (TPV) & Thermoelectrics (TE) Ceramic, heated by flame with recirculation and evne O2 enrichment (membranes), becomes a highly luminous, tuned source, emitting light and generating electricity through a PV cell Self powered appliances Cascading TPV and TE Setting up commercial prototype with client for water heating

35 Balance of plant To provide optimal operational conditions for optimal combined heat and power generation To be generic and simple* To minimize the MG interruptions To minimize water heater burner operation (cycling)

36 Vanadium-Redox Battery Energy Storage Canadian Manufacturer: VRB Power Systems Inc. First prototype unit shipped to customer site Specs: 3.3 kw max power output for 3 hours (10 kwh) Assess characteristics and performance Completed over 3000 hours and 120 full charge/discharge cycles at 60% depth of discharge No performance degradation observed so far System (VRB-ESS)

37 Conventional Fluorescent Lighting Efficient Lighting Coal-fired Electricity Generation Efficiency 20 % x 30% Overall efficiency = 6% CO 2 equiv effic = only 3% (coal-fired electicity)

38 Integrated Gas Lighting System Eliminate need for electricity by generating light directly by burning natural gas in optimized visually-radiant burner as a central source in building Distribute the light throughout the building by means of light pipes Capture rest of heat for space/wtr htg Co-gen without electricity generation!

39 Opportunities for Micro-CHP The preliminary results are very promising Special attention should be given to building integration A suitable thermal cooling will broader the application An optimal control strategy based on AI technologies should be developed High electrical efficiency is of little importance Exported electricity must have some value Virtual utilities Effective for peak shaving capabilities Potential for retrofit and combination with existing energy systems Incremental for high efficiency Combination with alternative generation systems

40 Review of Objectives Appreciate what micro-cogeneration is Understand the range of advanced microcogeneration technologies now impending on the North American marketplace Understand the potential energy, environmental and system advantages offered by micro-cogeneration See how you may have your own kw in your future.

41 This is a technology whose time is coming quickly

42 Microgen 2008 First International Conference and Workshop on Micro-cogeneration Systems and Applications April 29-May 1, 2008 Ottawa, Canada

43 For further information, contact me (Skip Hayden) Senior Research Scientist, D/S&T Director Integrated Energy Systems SBC, CETCO, NRCan 1 Haanel Drive Ottawa, Canada K1A 1M1 tel: (613) fax: (613) skip.hayden@nrcan.gc.ca