Application Study on Foundry Industrial Load Participation in Virtual Power Plant Valley-filling

By the end of 2025, the installed photovoltaic capacity in Zhejiang Province reaches 64.29 GW, making photovoltaic power the largest power source in the province. With the high penetration of grid-connected photovoltaic power, photovoltaic output is often mismatched with load demand during holiday low-load periods, when industrial and commercial electricity consumption decreases. This mismatch may cause reverse power flow and voltage limit violations, leading to prominent photovoltaic accommodation challenges. This paper proposes a market-oriented trading optimization strategy for foundry industry loads participating in virtual power plant valley-filling. It explores the valley-filling potential of the traditional foundry industry and constructs an electricity cost model for production scheduling optimization considering peak-valley price differences and valley-filling subsidies. By guiding foundry enterprises to implement off-peak production, the proposed strategy reduces enterprise electricity costs and improves photovoltaic accommodation efficiency. The feasibility of county-level small foundry clusters participating in valley-filling is verified, and the proposed model shows potential for wider application.