Sizing output around your household
What a typical 4-person household actually uses
A 4-person household in an average-size home typically uses somewhere around 6,500 to 8,000 kWh a year, though this swings a lot based on home size, climate, and whether anyone in the house has an EV. Occupant count alone doesn't tell the whole story, which is why this calculator also asks about your home and appliances. A DOE report on federal solar performance found an average energy ratio of 74.6% across its sample, a useful reference point when sizing a system against expected usage.
Why square footage matters alongside occupants
Occupants drive appliance and hot water use, but square footage drives heating, cooling, and lighting load independently, so a 4-person household in a 3,500 square foot home uses noticeably more than the same family in a 1,600 square foot home. Larger homes also tend to run more zones of HVAC, which compounds the difference. For a broader national baseline, the EIA's own household electricity data puts the average US residential customer at 10,791 kWh a year, though that figure covers all household sizes combined, and all-electric or larger homes often run higher.
How much an EV or pool changes the picture
Charging an EV at home for typical annual mileage adds roughly 3,200 kWh a year to a household's electricity usage, which is close to doubling the usage of a smaller household on its own. A pool with a pump and heater adds a smaller but still meaningful amount, especially in warmer climates where the pump runs longer each day. If an EV purchase is on the horizon rather than already part of your household, the EV charging load addition calculator can model that added usage in more detail before you commit to a system size.
Choosing a target offset instead of defaulting to 100%
Not necessarily every household should size to offset 100% of usage. Many households target somewhere between 80% and 110% of usage depending on local net metering rules, roof space, and budget, so it's worth treating 100% as a starting point rather than a fixed target. Check the output vs usage gap analyzer if you already have a system and want to see how close it comes to your actual usage.
What to do with this number next
Once you have a target output figure, compare it against what a specific system size would realistically produce using the annual output estimator, or head back to the performance and output hub for related tools. The payback period calculator takes that same figure and turns it into a year-by-year savings timeline.