Running our home on solar power alone was fine until evening rates started eating into the savings. I added a 10kWh lithium-ion battery last spring, mainly to shift energy from daylight into peak hours. The installer mounted it beside the inverter in our garage and connected it to the rooftop solar system. Setup took one afternoon; the app was paired before dinner, and I could see solar production, battery state of charge, and household consumption immediately.

The biggest change is what happens between 4:00 and 9:00 p.m. Before the battery, we pulled from the grid while cooking, running the dishwasher, and cooling the house. Now the battery covers that window. On sunny days it reaches 100% by mid-afternoon, then discharges after sunset. My monthly bill dropped by 25–35%. The exact amount varies, but avoiding expensive peak electricity has been more valuable than I expected. My battery payback will take time, yet the savings are visible enough to keep me happy with the purchase.

I did have one troubleshooting moment. The battery stopped discharging during a cloudy evening, even though the app showed 42%. I found that the backup reserve had accidentally been set to 40% during a firmware update. Lowering it to 15% restored normal discharge, and support confirmed nothing was wrong with the hardware. That incident taught me to check settings before assuming a battery fault.

I considered expanding the system, but this lithium battery is enough for our evening loads. The price of li ion battery was not small, and I compared solar storage quotes before ordering. Still, using more of my solar energy feels better than exporting everything and buying power back at the highest rate.