Analysis of the tripartite evolutionary game in the marketization of China's renewable energy-based electricity prices

The evolution of China's renewable power pricing regulation from subsidy-driven fixed feed-in tariffs (FIT) to market-oriented, quota-based renewable portfolio standards (RPS) is a crucial institutional transformation designed to advance the low-carbon energy transition. The government's price regulation of mandatory and non-mandatory quotas has a direct impact on the optimal production decision-making behavior of renewable and coal-fired power producers, which determines the effective substitution of fossil energy by renewable energy in China, and relates to the successful realization of the low-carbon energy transition. This article presents the construction of a tripartite evolutionary game model under both non-mandatory and mandatory quotas, employing MATLAB software to simulate and assess the effectiveness of a tradable green certificate (TGC) system in the presence of mandatory quotas. Based on stable equilibrium strategies, we discuss the impact of FIT on green certificate trading under four different subsidy withdrawal strategies and three quota and penalty scenarios. The results indicate the following. First, when renewable power producers certify and engage in green certificate trading, coal-fired power producers purchase green certificates, and the government implements mandatory quotas, the participants in the game achieve an equilibrium strategy combination. Second, the findings validate the effectiveness of the RPS-TGC model (i.e., the green certificate trading system in the presence of mandatory quotas) for electricity price regulation. Third, the root cause of the failure of China's current voluntary green certificate trading system is the government's non-mandatory quotas. Accordingly, it is proposed that the marketization of renewable electricity prices in China needs to adopt a fast-then-slow exit of FIT subsidies, with renewable energy power quotas set at 20% and penalty standards set at 1.5P.