Capacity configuration of hydropower-PV complementary station that is robust to the inter-annual variability in streamflow and PV energy

Conventional methods for sizing variable renewable energy (VRE) capacity integrated into hydropower are fed with several typical weather days or a single weather year dataset, which reduce computational complexity while neglecting the inter-annual variability of VRE and streamflow and yielding potentially unreliable results. This study proposes a novel tractable long-term model at hourly resolution to investigate the potential of hydro–VRE complementary operation for load following, reliable electricity supplying and to size the VRE capacity integrated into the hydropower stations . This methodology was applied to an actual hydropower-photovoltaic (PV) complementary station in China. We found that (1) PV capacity integrated into the hydropower is highly sensitive to the inter-annual variability of streamflow and PV energy; the PV capacity sized based on single-year-simulation ranges from 446 MW to 725 MW. (2) The PV deployment capacity based on 12-year-simulation is 510 MW. Compared with the PV deployment capacities based on single-year-simulation, it enables better hydropower-PV complementary load following performances and an average increase of 2.06 × 10 5 MWh in the annual electricity supply.