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Rappahannock County DominionREC Installer core area

Solar panels in Washington, Virginia: 1,328 kWh per kW per year

A south-facing kilowatt of panels in Washington makes about 1,328 kWh a year, 2.8% below the Virginia median. Power here comes from Dominion or REC; the numbers below use the Dominion rate of 15.20¢ per kWh (2025 average). Your bill shows which one serves you.

1,328

kWh / kW / year

PVWatts, south-facing

4.93

Peak sun hours / day

annual average irradiance

10,624

kWh / yr from 8 kW

a common home system

15.20¢

Dominion price

2025 residential avg

Monthly solar production per kW in Washington, VirginiaKilowatt-hours per month for a 1 kW south-facing system. Peak in Jul, low in Dec.050100150Jan88Feb94Mar116Apr123May124Jun124Jul138Aug122Sep118Oct105Nov93Dec82
NREL PVWatts v8, 1 kW DC, fixed roof mount, azimuth 180°, tilt 25°, 14% losses. Jul makes about 1.7× Dec.

Seasonality

Monthly solar production in Washington

Virginia net metering carries excess credits forward for 12 months, so Jul's surplus offsets Dec's shortfall. Systems are sized to annual usage rather than to the lowest month. How the calculator models net metering; the current rules by utility are on this Virginia incentives page, maintained by the installer behind this site.

Capacity factor: 15.2%. Elevation about 260 m. Compare every town on the city list, or see how roof direction, tilt and shade change the number.

Payback in Washington

Solar cost and payback for an average home in Washington

Assumes 1,038 kWh a month (≈ $158) at Dominion Energy's 2025 average price, Washington's PVWatts production, 3% annual rate growth and $2.78/W installed, no federal credit. Dollars are nominal. Change any of it in the calculator, or compare every utility in Are solar panels worth it in Virginia?

Run it with your bill

9.4 kW

System size

$26,132

Est. cost

$2,073

Year-1 savings

11.5 yrs

Break-even

$62,073

25-yr savings

$35,941

Net benefit

undiscounted

Utility

Electric utilities serving Rappahannock County

Rappahannock County is split between utilities. Rates are calendar-year averages; see all Virginia utilities for the full table.

UtilityTypeAvg price ¢/kWhAvg kWh / monthData year
Dominion EnergyInvestor-owned utility15.201,0382025*
Rappahannock Electric CooperativeElectric cooperative15.491,1952025*

Questions

Questions about solar in Washington

How much electricity does a solar system produce in Washington?
About 1,328 kWh per year for every kilowatt of panels on a south-facing roof, according to NREL's PVWatts. An 8 kW system would make roughly 10,624 kWh a year. East- or west-facing roofs make less; the calculator applies those factors.
Who is the electric utility in Washington?
EIA's service-territory data lists Dominion Energy and Rappahannock Electric Cooperative for Rappahannock County. Boundaries run through the locality; your bill shows which one serves you. Dominion's 2025 average residential price was 15.20¢ per kWh.
Is solar worth it in Washington?
For an average Dominion home (1,038 kWh a month), the default assumptions give a 9.4 kW system costing about $26,132 with a break-even around 11.5 years and $35,941 net benefit (nominal) over 25 years. Your bill, roof and shade change that; the calculator lets you enter them. The statewide picture is in “Is solar worth it in Virginia?”.
Where does the sun data come from?
NREL PVWatts v8 (8.5.0), using the 1110333.csv typical-year weather dataset for grid cell 1110333, about 3 km from the town center. Inputs: 1 kW DC, fixed roof mount, 180° azimuth, 25° tilt, 14% system losses. Typical-year data doesn't change year to year.

Solar production in towns near Washington

Sources: NREL PVWatts v8 (8.5.0, typical-year weather); EIA Form 861 2025 utility data and service territories; U.S. Census Bureau place coordinates. Formulas and assumptions on the methodology page.