Solar calculator for District of Columbia
Panels, system size, cost and payback for District of Columbia, from your own power bill.
The average District of Columbia home uses 639 kWh a month and pays 17.7 cents per kWh, which puts District of Columbia at above-average electricity prices, which helps solar savings. District of Columbia has both a heating and a cooling season, so the bill swings both ways and a full year of bills gives a better answer than one month. A south-facing fixed array there makes about 1,391 kWh per installed kW a year, and the worst winter month still gets 2.9 peak sun hours a day. Drop in your own bill below and the numbers on this page are replaced by yours.
A worked example for District of Columbia
Take the average home: 639 kWh a month, which is 7,668 kWh a year, at 17.7 cents per kWh (EIA, 2024 residential averages, as of 2026-11). Sized to cover all of that use, the tool returns 5.5 kWdc and 14 panels, needing about 294 square feet of roof. The installed estimate is $13,726 (national median, EnergySage H2 2025), yearly savings are about $1,357, and simple payback is 10.1 years, with no incentive applied.
Sun and yield in District of Columbia
We use 1,391 kWh per installed kW per year for District of Columbia, from NREL PVWatts v8 for the state's largest city at a 20 degree south-facing tilt (via TheGreenWatt, as of 2026-11). The darkest month averages 2.9 peak sun hours a day, which matters if you plan to go off-grid or size a battery. A different roof angle or heavy shade changes this, so treat it as a starting point.
Incentives
The 30% federal tax credit ended for homeowner purchases after December 31, 2025, so none is applied here. See the tax credit guide. Look up District of Columbia and your own utility for net metering terms and any local programs before relying on a payback number.
Planning estimate. Permits, interconnection approval and a licensed electrician are required for grid-tied systems.
Questions
How many solar panels does a District of Columbia home need?
The average District of Columbia home uses 7,668 kWh a year (EIA 2024). At about 1,391 kWh per installed kW, covering all of it takes 5.5 kWdc, or 14 panels. Your own bill will move that up or down.
How much does solar cost in District of Columbia?
For the average-home example the installed estimate is $13,726 at the national median of $2.49 per watt (EnergySage, H2 2025, as of 2026-11). We have no sourced District of Columbia price multiplier, so local quotes will differ.
Is there a federal solar tax credit in District of Columbia?
The 30% federal tax credit ended for homeowner purchases after December 31, 2025. Check your state, utility and local programs separately.
Where does the District of Columbia sun figure come from?
1,391 kWh per kW per year and 2.9 winter peak sun hours come from NREL PVWatts v8 runs for District of Columbia's largest city, compiled by TheGreenWatt (as of 2026-11). Real yield varies across the state.
Is my bill uploaded?
No. Your bill is read in your browser and never uploaded.