Savings and payback
See your solar savings at a low usage level, where a standard-size system often produces more than needed, and whether right-sizing makes more financial sense.
How it works
Step 1
500 kWh a month is pre-filled as a common low-usage benchmark; adjust it if your actual usage differs.
Step 2
See the right-sized system for your usage, and if you enter a standard system's production, exactly how much excess it would produce. For more on right-sizing, see the low usage home savings calculator, or the solar panel calculator for detailed sizing.
A standard 6.5 kW system would fully offset a 500 kWh a month home's bill, with about 3,490 kWh a year of excess production beyond what's needed, so a smaller, less expensive system would likely make more financial sense than installing a size meant for higher-usage households, as covered on the payback period calculator. The US Department of Energy's homeowner's guide to going solar walks through the same decision step by step.
For full offset at 500 kWh a month, roughly 6,000 kWh a year, a system around 4.1 kW would match usage closely, about a third smaller than the 6.5 kW example used elsewhere on this site. A right-sized system like this typically costs less upfront while still fully covering the bill. If you have not sized the system yet, start with the system size by monthly kwh usage and bring its kilowatt figure back here.
It depends on your utility's net metering policy. Some utilities credit excess production at full retail value, others at a lower wholesale rate, and some cap how much can roll over, so oversizing doesn't always pay off proportionally. Check the bill credit rollover calculator for how unused credits carry forward under your specific policy. Utility rates drive the whole savings calculation, and the US Energy Information Administration's electricity data track them state by state.
It's below the typical US household average of 800 to 1000 kWh a month, more common for smaller homes, apartments, single occupants, or households without major electric loads like AC or EV charging. See the 1000 kWh a month calculator for the more typical benchmark. The production figure behind this estimate comes from the real world vs nameplate output gap calculator, which models output for your location and roof.
Questions
A standard 6.5 kW system would fully offset a 500 kWh a month home's bill, with about 3,490 kWh a year of excess production beyond what's needed, so a smaller, less expensive system would likely make more financial sense.
For full offset at 500 kWh a month, roughly 6,000 kWh a year, a system around 4.1 kW would match usage closely, about a third smaller than the 6.5 kW example used elsewhere on this site.
It depends on your utility's net metering policy. Some utilities credit excess production at full retail value, others at a lower wholesale rate, and some cap how much can roll over, so oversizing doesn't always pay off proportionally.
It's below the typical US household average of 800 to 1000 kWh a month, more common for smaller homes, apartments, single occupants, or households without major electric loads like AC or EV charging.
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