Operation, optimization and additional market participation of households with PV battery storage system and power-to-heat application

Angenendt, Georg; Sauer, Dirk Uwe (Thesis advisor); Engel, Bernd (Thesis advisor)

Aachen : ISEA (2019, 2020)
Book, Dissertation / PhD Thesis

In: Aachener Beiträge des ISEA 139
Page(s)/Article-Nr.: 1 Online-Ressource (VI, 221 Seiten) : Illustrationen, Diagramme

Dissertation, Rheinisch-Westfälische Technische Hochschule Aachen, 2019

Abstract

Sector coupling allows the use of electricity from renewable sources in different sectors to reduce their greenhouse gas emissions. Among others, renewable electricity from domestic photovoltaic systems can be used in the heating sector through power-to-heat coupling. The power generated by the photovoltaic system is then used for space heating as well as hot water preparation. In this dissertation, a detailed simulation model of an integrated home consisting of a photovoltaic system, a battery storage and power-to-heat coupling is developed to investigate cost reduction potentials. Cost reduction can be achieved by advanced operation strategies, optimization of the component sizes and market participation.Operation strategies: This thesis presents advanced operation strategies for the electrical and thermal system and examines the gain in efficiency by combined operation strategies. Forecast-based operation strategies that reduce battery aging and costs are developed and compared to state-of-the-art operation strategies. The results of the thesis indicate that advanced operation strategies can reduce the annual costs of photovoltaic battery energy storage systems up to 12 %.Optimization of component sizes: The most important aspect to improve the economics of integrated homes is system sizing. Dimensioning of the different system components heavily influences the economics of photovoltaic battery storage systems with power-to-heat coupling. The thermal and electrical load profile as well as the solar radiation profile must be considered to find optimal component dimensions. An optimization tool is presented that finds the most economic sizing for each system component. The results indicate that integrated homes with optimized component sizes and advanced operation strategies are economically competitive to households with fossil heating concepts. Additional market participation: During winter, storage systems in integrated homes are not used to their full capacity due to the low solar irradiation. These unused capacities can be used to improve the economics of integrated homes by implementing a second-use scheme. Second-use describes the value stacking of home storage operation and participation on energy markets, e.g. the control reserve market. Besides enhanced economics, a participation in the control reserve market can improve grid stability and hence support further integration of renewable energies. A major advantage of integrated homes with power-to-heat coupling in comparison to standalone battery storage is the additional flexibility to absorb the negative control reserve power, provided by the heating sector. This allows an extension of the operating limits of a power-to-heat coupled battery. This thesis presents a dual-use operation of an integrated home participating in the primary and secondary control reserve markets. Results show that a dual-use operation can increase the 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 net cost reductions of up to 12.5 % are possible.