The impacts of storing solar energy in the home to reduce reliance on the utility

There has been growing interest in using energy storage to capture solar energy for later use in the home to reduce reliance on the traditional utility. However, few studies have critically assessed the trade-offs associated with storing solar energy rather than sending it to the utility grid, as is typically done today. Here we show that a typical battery system could reduce peak power demand by 8–32% and reduce peak power injections by 5–42%, depending on how it operates. However, storage inefficiencies increase annual energy consumption by 324–591 kWh per household on average. Furthermore, storage operation indirectly increases emissions by 153–303 kg CO2, 0.03–0.20 kg SO2 and 0.04–0.26 kg NOx per Texas household annually. Thus, home energy storage would not automatically reduce emissions or energy consumption unless it directly enables renewable energy. Tariff structures and network constraints might incentivize storing solar energy in the home to reduce reliance on utilities. This study shows that storing solar energy rather than exporting it to the utility grid could increase electricity consumption as well as CO2, SO2 and NOx emissions.