How time-of-use (TOU) electricity rates affect solar battery economics
If your utility has TOU rates, the per-kWh rate that you pay for electricity will change depending on the time of day. Electricity will cost more during “peak hours” when demand for electricity is high, typically in the late afternoon and evening. Electricity rates are lower during the daytime when home electricity use is lower and solar panels are at their most productive. If your utility uses TOU rates, you can benefit from home energy storage by using electricity from your solar batteries during peak hours when utility electricity rates are at their highest.
TOU rates are becoming more common in the U.S., with California leading the way. Under a new solar policy, any homeowner who installs solar panels in the Golden State will automatically be required to pay TOU rates instead of a single per-kWh rate.