Impact of Photovoltaic Plant Tilt on the Need for Storage

This paper explores the application of optimizing tilt of photovoltaic (PV) plants as a statewide strategy to best match the California statewide load over the year and thus minimize storage requirements for a carbon-free grid. Through a simple cost model and energy balance model examining PV + storage in isolation, we show that, even though horizontal trackers produce the lowest cost electricity when the timing of generation is ignored, high-tilt PV plants have the potential to reduce overall system cost substantially by reducing the required storage capacity and by better utilizing surplus electricity. California should consider tilted PV configurations in capacity expansion planning and consider PV electricity pricing or incentives that encourage new PV installations that better match the seasonal load to reduce storage requirements.