Carbon-free Electricity Supply in a Cournot Wholesale Market: Israel

Abstract

We develop a two-stage model to analyze a Cournot wholesale electricity market in which competing firms use photovoltaics augmented with batteries (PVB) or combined cycle gas turbines (CCGTs) to meet time-varying demands. Capturing the complex interactions of output and investment decisions made by multiple profit-maximizing PVB and CCGT firms, our model yields the market’s long-run equilibrium of capacity mix and short-run equilibrium of electricity generation and price levels. Accounting for the sun’s irradiation that determines solar generation level, our model computes the battery cost reduction necessary for batteries entering the optimal capacity mix. Using Israel as a case study, we show how declining battery cost may cause PVB firms to displace CCGT firms, resulting in carbon-free electricity supply as a market-based outcome. The battery cost threshold initiating this outcome is ~24% of CCGT’s capacity cost, implying that natural gas is a transitional fuel in Israel’s pathway to deep decarbonization.