Optimal way to achieve renewable portfolio standard policy goals from the electricity generation, transmission, and trading perspectives in southern China

An important strategy to stimulate renewable energy consumption is adherence to renewable portfolio standard (RPS), which has cost advantages over feed-in tariff (FIT). China published its provincial RPS goals in 2018 and, since then, it has been pressurizing provinces to realise the goals. This study develops a mid-to long-term optimisation model for the area served by the China Southern Power Grid Corporation (CSPGC) based on power-plan constraints and RPS goals for 2016-2030. The results indicate an optimal method for the five provinces in the CSPGC area to achieve their RPS goals based on the power-plan constraints till 2030. For electricity generation, wind power development should precede solar power development; further, hydropower development is particularly significant for the region. To facilitate electricity transmission, the construction of transmission lines between Guangdong and Yunnan should be prioritised. In electricity trading, RPS policy implementation will cause Guangdong to buy more electricity from western provinces, aiding the completion of the West-East Electricity Transfer Project. Moreover, in the CSPGC area, RPS policy implementation will not significantly affect the total electricity supply cost due to the development of low-cost hydropower in the region.