Bidding in German Electricity Markets—Opportunities for CHP Plants

Abstract

Since the liberalisation of the German energy markets, supply companies strive to gain additional revenues by trading in different electricity markets. Thus, trading strategies have to be adjusted to lower but more volatile energy prices caused by a rising share of renewable energy feed-in. Due to the increasing importance of combined heat and power (CHP) plants, an energy supply company is considered that operates a CHP plant with heat storage. A new modelling approach is presented to support generation companies scheduling their participation in two sequential electricity markets, the balancing market and the day-ahead spot market. In both markets, specific bidding procedures for trading exist. To derive optimal bidding strategies for CHP plants, we formulate the bidding problem as an innovative and detailed multistage stochastic programming model taking into account the sequencing of market clearing. The optimisation model simultaneously determines the operation of the CHP plant and heat storage device. An exemplary case study illustrates the benefit from coordinated bidding in sequential electricity markets.