Abstract
The European Energy Exchange (EEX) day ahead spot market for electricity in Germany shows significant
variations in prices between peak and off-peak hours. Being able to shift electricity production from offpeak
hours to peak hours improves the profit from CHP-plant operation significantly. Installing a big thermal
store at a CHP-plant makes it possible to shift production of electricity and heat to hours where electricity
prices are highest especially on days with low heat demand. Consequently, these conditions will
have to influence the design of new CHP-plants. In this paper, the optimal size of a CHP-plant with thermal
store under German spot market conditions is analyzed. As an example the possibility to install small
size CHP-plant instead of only boilers at a Stadtwerke delivering 30,000 MWh-heat for district heating
per year is examined using the software energyPRO. It is shown that, given the economic and technical
assumptions made, a CHP-plant of 4 MW-el with a thermal store participating in the spot market will be
the most feasible plant to build. A sensitivity analysis shows to which extent the optimal solution will
vary by changing the key economic assumptions.
© 2009 Elsevier Ltd. All rights reserved.
| Original language | English |
|---|---|
| Journal | Applied Energy |
| Volume | 86 |
| Pages (from-to) | 2308–2316 |
| ISSN | 0306-2619 |
| DOIs | |
| Publication status | Published - 2009 |
| Externally published | Yes |
Keywords
- Cogeneration
- CHP
- Feasibility study
- Spot market
- Thermal store
