Open-Circuit Solar Fuel Stability

The rising global mean temperature due to the increase in atmospheric CO2 concentration necessitates a shift to net-zero carbon emission energy systems.1 Decarbonization of the electric grid requires generation from renewable energy sources like solar radiation.2 The supply of energy from the sun is abundant; an hour of incident sunlight on Earth is enough to power the world for a year.3 However, electricity produced by solar photovoltaics is non-dispatchable and consequently the supply of solar energy is constrained by the intermittent nature of sunlight.4 Energy demand is also time varying with peak demand often occurring in the evening with low solar irradiance, necessitating for grid-scale energy storage to address the temporal mismatch between renewable energy supply and demand