Optimal allocation of renewable power sources for outbound supporting in trans-regional power transmission of China

AbstractThe large-scale absorption of renewable energy is key to promoting the low-carbon transition of power system, but renewable resources are far away from load centers in China. In recent years, China has been advancing the construction of trans-regional power transmission channels to achieve renewables’ grid interconnection. Outbound supporting power sources are the essential infrastructure to ensure effective operation of these channels, and their optimal allocation need nationwide systematic research. This paper constructs a trans-regional dispatch and supporting power source optimization allocation model involving seasonal characteristics, load profiles, and renewable energy policies. It rationally allocates the planned renewable installed capacity between local supply and outbound supporting, and a total of 79.0 GW of wind power, 31.0 GW of photovoltaic power, and 26.3 GW of hydropower capacities would been allocated for outbound supporting in the 14th Five-Year Plan period. Meanwhile, it provides optimal hourly regional power output and line transmission plans at minimal cost. The results indicate that the newly added hydropower in Southwest and Yunnan, and wind and solar power in Northwest and North, are the key guarantees for East and South to achieve renewable power absorption responsibility targets; the thermal power would fluctuate significantly during some seasons for renewable power absorption, bearing great peak-shaving pressure.