Energy offset
The percentage of your yearly electricity use that your solar panels produce — a 100% offset means generation equals consumption over a year.
Energy offset is the ratio of annual solar production to annual home consumption. A system sized for '100% offset' generates roughly as many kilowatt-hours over a year as the home uses, though it overproduces in summer and underproduces in winter.
Under full retail net metering, 100% offset can zero out your energy charges. Under net-billing tariffs like NEM 3.0, exported surplus is credited well below retail, so a battery — not a bigger array — is what captures the value of that overproduction.
Put it to work
See also