Price arbitrage optimization of a photovoltaic power plant with liquid air energy storage. Implementation to the Spanish case

The large deployment of photovoltaic power planned in Spain for 2030 will strongly affect electricity prices. The rapid transition toward higher shares of intermittent renewable energy is challenging. Energy storage will be most probably necessary to enhance renewable sources manageability, to balance the grid and to guarantee electricity supply security. A PV power plant (100 MWp) located in Spain has been modelled to simulate its instantaneous energy generation. In parallel, two types of Liquid Air Energy Storage plants (adiabatic and enhanced with combustion) have been explored as alternative for storing PV energy when market prices are not interesting and selling it when prices are higher. A simple arbitrage algorithm has been specifically designed at this end. A techno-economic analysis allows determining the optimum size of the storage plant in terms of benefits. The study reveal that benefits may reach 17 (SIC)/MWh of sold energy in the case of LAES plant enhanced with natural gas combustion, although the resulting CO2 emission factor would be slightly larger than the Spanish grid average. Alternatively, burning bio-methane will ensure zero emissions, but it would be profitable provided the fuel cost is less than 41 (SIC)/MWh. (C) 2021 Elsevier Ltd. All rights reserved.

Automated summary

The large-scale deployment of photovoltaic power planned in Spain by 2030 will have a significant impact on electricity prices. Energy storage is likely necessary to manage the increasing share of intermittent renewable energy and ensure grid balance and electricity supply security. Techno-economic analysis reveals potential benefits and challenges associated with different storage options, such as Liquid Air Energy Storage plants.