Firm Photovoltaic Generation through Battery Storage, Overbuilding, and Proactive Curtailment

With the prevailing recognition and implementation of carbon-neutral policies, the proportion of solar photovoltaic (PV) in the energy mix continues to rise. To mitigate the negative impact of variable PV power injection into the power grid, firm solar power generation strategies receive more and more attention. This paper elaborates on a counter-intuitive but effective solution to reduce the firm-generation cost of PV, namely, battery storage, overbuilding, and proactive curtailment. A simulation case study considers a 1-MW PV plant in the cold climate of Harbin, China, whose annual generation equals the annual energy demand of a 0.17 MW constant load. Results show that a 3x-oversized PV plant paired with battery storage and proactive curtailment can reduce its firm-generation cost by 79.67% as compared to a PV plant with no overbuilding but with proactive curtailment and larger battery storage. In a future power grid dominated by variable renewable energy, battery storage, overbuilding, and proactive curtailment are profoundly rewarding.