To address the challenges of heavy operation and maintenance electricity costs and difficulties in securing OM funds at rural sewage treatment stations in the rainy regions of eastern Guangdong

this paper proposes a grid-connected system design featuring oversized photovoltaic capacity and coordinated energy storage. The system operates under the principle of self-consumption of on-site generation and storage of surplus power

and adopts a power supply strategy based on photovoltaic priority

energy storage coordination

and grid power backup. Taking a 10 m³/d rural sewage treatment station in Puning

Guangdong as a case study

this paper completes load statistics

equipment selection

and sizing calculations for photovoltaic modules

energy storage

and inverters

and carries out nine-month cross-season operation monitoring.