Most homeowners choose to store their solar energy by using a solar battery. Technically, you can store solar energy through mechanical or thermal energy storage, like pumped hydro systems or molten salt energy storagetechnologies, but these storage options require a lot. Adding solar energy storage typically costs between $12,000 and $20,000. For example, a Powerwall battery costs about $15,500 fully installed by Tesla, whereas a Panasonic EverVolt. Solar energy storage systems are becoming more popular every year and it's no surprise why - here are just a few of the benefits of installing. If you live somewhere that experiences frequent electric grid power outages, or if your utility uses Time-of-Use rates, then solar battery storage will be a worthwhile investment for you. Otherwise, solar batteries are still pretty expensive, so they won't pan out.