Towards an intermittency-friendly energy system

Transcription

1 Towards an intermittency-friendly energy system Morten Boje Blarke, Ph.D, Assist. Prof., Aalborg Universitet

2 The pre-sustainable energy system Mobility Power exchange Power-only plants Electricity Electricity Fuels Cooling Heat-only boilers Heat Heating Resources Conversion Exchange Demand

3 The pre-sustainable energy system

4 Towards a distributed energy supply 16 central power plants 1985 decision: No nuclear Domestic natural gas availability from North Sea Energy 2000 in 1990, the world s first sustainable national energy plan The wind tale of context and opportunity

5 Towards a distributed energy supply Some 650 distributed cogenerators A cogenerator is a plant that efficiently coproduces heat and electricity, replacing individual boilers and central power plants An important part of life and reason in many local communities, most plants are operated non-profit by co-operative societies

6 Existing wind farms (on-shore, off-shore) Future options for off-shore farms (200 MW pies)

7 Intermittency calls for supply-demand intelligence 2008 (20 % wind) 2025 (50 % wind)

8 The first generation sustainable energy system (1G) Vindkraft Wind power etc. etc. Intermittent Diskont. elektricitet power Power Eludveksling Exchange Electricity Elektricitet Electricity Brændsler Fuels Power Kraftværker plants Kraftvarme Cogen Cooling Køling Boilers Kedler Heat Varme Heat Solvarme Solar heat etc. etc. Intermittent Diskont. varme heat Thermal Termisk Storage lagring Exchange Resources Conversion Demand and storage

9 Electricity demand Central power plants Distribution cogeneration Wind power MW

10 Electricity demand Total capacity Distributed capacity MW

11 Wind, Demand West Denmark, January MW January 2007

12 Wind, Distributed Generation, Demand West Denmark, January MW January 2007

13 Wind, Distributed Generation, Demand, Spot Market Price West Denmark, January MW January 2007

14 Two major intermittency adaption instruments 1. Progressively, since 2005, all distributed cogenerators below 5 MWe have been forced to operate on market conditions (spot market and balancing markets) 2. A new law (L1417) the electric boiler law stimulates the strategic use of electricity in district heating by reducing the tax on electricity used in electric boilers by 70% down to a level similar to that of competing fuels

15 R c = ( e ( e e e m ) m 2 )( d ( d d m ) d m ) 2 Exercise: Analyzing the intermittency-friendliness of distributed generation in a wind-rich energy system 1. The relocation coefficient: the statistical correlation between net electricity exchange between plant and grid, and the electricity demand minus intermittent renewable electricity production. 2. The relocation coefficient is useful for Policy analysis: Evaluating the overall intermittency friendliness of distributed generation with respect to a maximum relocation coefficient given by market conditions and operational strategies. 2. Project planning: Evaluating the intermittency friendliness of individual power producers, storage options, and electricity consumers. The relocation coefficient may be used to identify alternative options for increasing the intermittency friendliness of supply or demand.

16 Exercise results and discussion 60% 50% 51,7% 50,2% 48,4% 55,7% 56,9% 56,4% 40% 30% 30% 28% 26% 23% 23% DG share 30% Wind share DG Windfriendliness 20% 10% 21% 23% 24% 22% 26% 24% 0%

17 One of the most important research questions of the 21st century: How may the energy system become intermittency-friendly? - and which consequences will it have for society, economy, and the environment?

18 The pre-sustainable energy system

19 First generation sustainable energy system (1G) Vindkraft Wind power etc. etc. Intermittent Diskont. elektricitet power Power Eludveksling Exchange Electricity Elektricitet Electricity Brændsler Fuels Power Kraftværker plants Kraftvarme Cogen Cooling Køling Boilers Kedler Heat Varme Heat Solvarme Solar heat etc. etc. Intermittent Diskont. varme heat Thermal Termisk Storage lagring Exchange Resources Conversion Demand and storage

20 Second generation sustainable energy system (2G) Vindkraft Wind power etc. etc. Intermittent Diskont. elektricitet power Power Eludveksling Exchange Electricity Elektricitet Electricity Brændsler Fuels Tri- and Kraftvarme Quad-gen Mechanical Varmepumpe Heat Cooling Cooling Køling Heat Varme Heat Solvarme Solar heat etc. etc. Intermittent Diskont. varme heat Thermal Termisk Storage lagring Exchange Resources Conversion Relocation Demand and storage

21 Third generation sustainable energy system (3G) Fuel storage Mobility Vindkraft Wind power etc. etc. Intermittent Diskont. elektricitet power Power Eludveksling Exchange Electricity Elektricitet Electricity Brændsler Fuels Kraftvarme Tri- and Kraftvarme Quad-gen (el. QUAD) Mechanical Varmepumpe Heat Cooling Electricity storage Cooling Køling Heat Varme Heat Solvarme Solar heat etc. etc. Intermittent Diskont. varme heat Thermal Termisk Storage lagring Exchange Resources Conversion Relocation Demand and storage

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24 = % efficiency (COP = 3)

25 Cogenerator District heating Electricity grid

26 Cogenerator with thermal storage District heating Thermal Storage Electricity grid

27 Cogenerator with heat pump?? (something s missing!) District heating Compressor Expansion

28 Cogenerator with heat pump (e.g. ground heat) District heating Compressor Expansion

29 Cogenerator with heat pump - for which heat recovered from fluegasses is used for low-temperatur (integrated) heat source District heating Compressor Expansion

30 Cogenerator with heat pump, heat recovery, and cold storage District heating Compressor Expansion

31 Cogenerator with electric boiler District heating

32 A short-term future of cogeneration? District heating Compressor Expansion

33 Findings: The relocation coefficient Relocation Coefficient 0,6 0,55 0,5 0,45 0,4 0,35 0,3 0,25 0,2 0,15 0,1 0,05 0 Ref erence A B C D E F Options 1. Options for adding a heat pump or electric boiler increases the windfriendliness of the plant, currently at 0,50, up to 0, A small heat pump (that adds 20 % heat capacity) with cold storage (that increases Rc) is more wind-friendly than a full-size electric boiler.

34 Findings: System-wide CO2 emissions Net CO2 Emissions PMT A B C D E F Options 1. Options constrained by availability of lowtemperature heat source increase CO2 emissions. 2. Disallowing concurrent operation of heat pump and cogenerator helps. 3. Unconstrained options (ground source heat pump, electric boiler) reduce CO2 emiss.

35 Findings: Economic costs of heat production Levelized Economic Costs Per Unit Demand Sold 0,23 0,22 0,21 0,2 0,19 0,18 0,17 0,16 0,15 0,14 0,13 0,12 0,11 0,1 0,09 0,08 0,07 0,06 0,05 0,04 0,03 0,02 0,01 0 Ref erence A B C D E F Options 1. Economic costs (including carbon credits, avoided costs) of heat production increase from 7 % up to 84 %.

36 Findings: Relocation cost-effectiveness Levelized Economic Cost Per Increased Percentage R A B C D E F Options 1. Adding a cold storage increases cost-effectiveness. 2. Adding a small ground source heat pump and a cold storage could be the most costeffective of options 3. The most costeffective heat pump options are more cost-effective than the electric boiler option.