Applications and economics of combined PV and battery systems for commercial & industrial peak shifting

In this study, combined PV and battery systems were designed based on typical load profiles for nine commercial and industrial (C&I) end-users. The battery systems were used to manage monthly utility demand charges. Our model optimizes battery capacity and PV charging, with the objective of minimizing monthly peak energy demand charges. We demonstrate system performance within the utility territories of Connecticut Light and Power and California´s Pacific Gas and Electric (PG&E). The cross comparison between California and Connecticut illustrates the effects of varying rate structures and solar potential on the value of energy storage systems. Our research demonstrates that adding battery storage is economically viable, without subsidies, at current prices in California. By 2025 battery storage is anticipated to allow for significant economic and operational benefit in California and to reach viability in Connecticut. We find substantial synergies when combining PV and battery, compared to each system separately.