Flexibility options of CHP: bringing together renewable energies and efficiency (German example) Adi Golbach 1
The question Growing share of fluctuating wind and solar power is changing the generation requirements How does cogeneration fit into these requirenments? 2
Development of RES supply share in Germany Electricity Final Energy Heat Car fuels 3
RES objectives of the German Energiewende 90% RES-share in electricity consumption Historical development and targets 80% 70% 60% 50% 40% 30% Historisch EEG12 EEG14 oberer Wert EEG14 unterer Wert Trend aktueller Plan 20% 10% 0% 4
Load/ Capacity [GW] Growing needles call for flexibility 20 % Wind & Solar 40 % Wind & Solar 80 % Wind & Solar red green Elt. Load Generation Wind & Solar Source: Prof. Dr.-Ing. habil. Ingo Stadler/ Westfalen Wind GmbH 5
1 352 703 1054 1405 1756 2107 2458 2809 3160 3511 3862 4213 4564 4915 5266 5617 5968 6319 6670 7021 7372 7723 8074 8425 Perspectives 2030 expected Residual loads (blue) 79 % RES-Generation (scenario RES association) GW Szenario 2030 120 100 80 60 40 20 - (20) (40) (60) Last Erzeugung Wind, PV & Laufwasser Residuallast Source: Norbert Krzikalla et al. (BET): Möglichkeiten zum Ausgleich fluktuierender Einspeisungen aus Erneuerbaren Energien, April 2013 Folie 6
7 Does cogeneration fit into these new requirenments?
CHP load in GW Outdoor temperature Example CHP load in 2005 Hours on one year Source: FfE, CO2-Verminderung in Deutschland, 2009 8
Load in kw Electricity and heat demand over the year Office building 12,000 m³ Electricity Heat Source: Transferstelle Bingen 9
¼ hour load kw el Electricity demand over one day Example appartment house Quelle: Transferstelle Bingen 10
Load curve of a District heating system 100% 80% 60% 40% 20% 0% 0 730 1460 2190 2920 3650 4380 5110 5840 6570 7300 8030 8760 11 Source: Prognos
Sorted annual heat load curve district heating CHP design & operation without heat storagge Boiler CHP h 12
Sorted annual heat load curve district heating CHP design & operation with heat storage Boiler CHP h 13
Market as control center : EPEX-Prices indicate the relative scarcity Example. Week 12-19.8.14 Power exchange prices give incentives to switch CHP on or out Convent. PP solar Wind Hydropower Bioenergy Power load Electr. demand /MWh Negative Prices: unflexible must-run - power plants overburden the export market Source: -- power price EPEX-Spot
Example CHP plant flexible operation 420 kw existing + 1.562 kw additional Schedule winter week: many operating hours Due to higher capacity more CHP heat production higher overall efficiency EPEX price Power production demand-oriented operation: tranquility for the low price time Heat production Heat storage recharging and discharging in the daily rhythm
Spring Week: low number of operating hours Bedarfsorientierter Operation at high Betrieb möglichst zur price hours only Hochpreiszeit Heat storage: bridging rest together with small CHP 16
17 Example of a Danish CHP with heat stoarag (Ringkøbing)
Heat load MW Heat oriented CHP design & operation 62.5 50.0 37.5 Sorted annual heat load Boiler 25.0 12.5 0.0 CHP Days of the year 18
Heat load MW Power oriented CHP & operation 62.5 62.5 Jahresdauerlinie des Wärmebedarfs 50.0 37.5 25.0 50.0 37.5 25.0 Sorted annual heat load Heizkessel BHKW 12.5 12.5 CHP 0.0 0.0 Days Jahrestage of the year (d) Jahresdauerlinie des Wärmebedarfs 19
Heat load MW Wärmeleistung MW Monvalent design 62.5 62.5 50.0 50.0 BHKW 37.5 25.0 37.5 25.0 CHP 12.5 12.5 0.0 0.0 Days Jahrestage of the year (d) 20
District heat production in % of maximum Low Correlation between CHP and solar power In cold and very cold hours PV generation is low. PV generation in % of maximum Source: Prognos AG 21
District heat production in % of maximum Correlation between DH CHP and wind power In cold and very cold hours wind power generation is low. High wind power generation in the transition period. Wind power generation in % of maximum Source: Prognos AG 22
CHP Roadmap compatible with RES development? Business level economic potential Reference Scenario Target Scenario Socioeconomic potential 185 TWh/a CODE2 CHP Roadmap CHP potential CHP compatible power generation
The heat view CHP is not only the most efficient way of power production but also the most efficient way of heat production. As heat will be needed for room heating and industrial processes also on the long run in the future, the electricity produced as a by-product to heat (i.e. in cogeneration) has the same ecological value as wind or solar power, because not using this electricity source would mean squandering it. Saving energy is the best energy source. 24
Some more aspects CHP can very well interact with electrical heat pumps CHP generate electricity in high price hours HP use electricity in low price hours Power-to-heat systems CHP can also use wind gas from power-togas -systems
Some pictures
27 Modern CHP with a heat storage
Biogas CHP with gas storage 1,500 m³ biogas storage 1200 kw el 1224 kw th CO2 saving 7,000 ton per year 28
2 medium sized CHP plants in Denmark with heat storage tanks 29
30 The future
31 Cogeneration for the people
The future of electricity production today will be decentralized tomorrow: Cleaner, cheaper, more reliable 32
Summary With growing shares of fluctuation power production from wind and solar more and more flexible production technologies are needed to cover the residual loads. Modern CHP technologies are flexible and different to electricity only power plants also high efficient. The CHP electricity will be produced in times with low wind and solar power production and high electricity prices, which indicate the relative scarcity on the market. By use of appropriate heat storage tanks the heat produced in cogeneration with electricity can be used later, as heat demand pattern is different from the residual electricity demand pattern. With CHP the residual electricity demand can be completely covered and thus security of supply be ensured without power-only-plants, i.e. without any compromise regarding energy efficiency. So we do not need new power only plants in future, neither for energy efficiency nor for security of supply. A growing CHP share means an intelligent and cost effective interaction between covering electricity supply and heat supply considering all objectives security of supply, economy, decarbonisation using limited energy resources as efficient as possible. 33
Thank you for your kind attention more Information and connection: adi.golbach@kwkkommt.de www.kwkkommt.de (German) Linkedin: Adi Golbach (English) 34