Participating in the control reserve market with PV battery energy storage systems and power-to-heat application

— One way to enhance the penetration of renewable energies in residential homes is to use renewables in the heating sector. Integrated homes combine PV battery storage systems with heat pumps to use PV-generated energy for heating. During winter, storage systems and especially batteries in an integrated home are not used to their full capacity due to low solar radiation. This potential can be used to enhance the economics of integrated homes by applying a second use scheme. Second use describes the value stacking of home storage operation and participation on reserve markets, as it is the case for this publication. In Germany, markets for primary and secondary control reserve are the most promising for integrated homes. An advantage of integrated homes with power-to-heat coupling in comparison to standalone battery storage system is the additional flexibility to absorb negative control reserve power provided by the heating sector. This allows an extension of the operating limits of a power-to-heat coupled battery. Advantages of integrated homes in comparison to stand-alone battery systems are investigated. Results show that a dual-use operation with participation on the control reserve market can increase profitability of residential storage systems. The economics of the market participation are highly sensitive to numerous factors. Participating on the negative secondary control reserve market can lead to reduced annual cost up to 14.5 % in the investigated scenario. These savings are mainly driven by free-of-charge energy. If a system participates on the primary control reserve market, savings are mainly driven by additional revenues from market remuneration. Annual cost reductions up to 12.5 % are possible. Savings include costs for communication. Costs for market access are not minded.