A worked example: 8 kW in Washington, D.C.
An 8 kW system — about 19 × 425-watt panels — at Washington, D.C.'s assumed installed cost of $2.70–$3.55 per watt runs roughly $21,600–$28,400 before incentives. At about 1,300 kWh of production per installed kW, it would generate around 10,400 kWh per year. Valuing self-consumed electricity at the assumed $0.18/kWh retail rate and exports conservatively, first-year savings land near $1,543 — a simple payback of roughly 14–18 years.
There is no federal tax credit in that math: the Section 25D residential credit ended for systems installed after December 31, 2025. State or utility incentives, where they exist, would shorten payback from here.
Average cost of solar panels in Washington, D.C. by system size
Most Washington, D.C. quotes land between 6 and 12 kW. At the state's assumed $2.70–$3.55 per watt, here is what each size costs to install, what it produces, and how long it takes to pay for itself on electricity savings alone — no incentives applied.
| System size | Panels | Installed cost | Annual production | Est. payback |
|---|---|---|---|---|
| 6 kW | 15 | $16,200–$21,300 | 7,800 kWh | 14–18 yrs |
| 8 kW | 19 | $21,600–$28,400 | 10,400 kWh | 14–18 yrs |
| 10 kW | 24 | $27,000–$35,500 | 13,000 kWh | 14–18 yrs |
| 12 kW | 29 | $32,400–$42,600 | 15,600 kWh | 14–18 yrs |
Size should follow your electricity usage, not a round number — these are reference points, not a recommendation. Note that cost per watt rises on smaller systems, because permitting, labor and the inverter do not shrink with the array.
What solar costs per kWh in Washington, D.C.
Spread across a 25-year life, with 0.5%/yr panel degradation and no financing cost, solar electricity in Washington, D.C. works out to roughly 8.8¢–11.6¢ per kilowatt-hour. The Washington, D.C. retail rate this page assumes is 18.0¢. That gap — not the sticker price — is what determines whether solar pays here, and it is why a sunnier state with cheap electricity can be a worse investment than a cloudier one with expensive electricity. See how every state compares on cost per kWh.
Net metering and export rates in Washington, D.C.
The District requires full retail net metering with credits that roll over indefinitely.
Export rules are worth reading as an incentive, because they set what every kilowatt-hour you do not use on site is worth — see how Washington, D.C. compares with every other state on net metering.
Washington, D.C. solar incentives
D.C. SRECs have traded in the hundreds of dollars per MWh — a typical home system can earn thousands per year — and Solar for All serves income-qualified households. Verify current SREC prices.
The most valuable program is the most valuable srec market in the country. With no federal credit for 2026 installs, state and utility programs are now the whole picture — see the full Washington, D.C. incentives guide.
What changes a Washington, D.C. solar quote?
Equipment, roof condition, electrical upgrades, permitting, labor, system size, batteries and financing can all change the installed price. Savings also depend on the specific utility rate, how much solar electricity the home uses directly, and what the utility pays for exports.
Frequently asked questions
What is the average cost of solar panels in Washington, D.C.?
The average installed cost in Washington, D.C. runs $2.70–$3.55 per watt before incentives, which puts a 6 kW system at $16,200–$21,300, an 8 kW at $21,600–$28,400, and a 10 kW at $27,000–$35,500. Spread over a 25-year life, that works out to about 8.8¢–11.6¢ per kilowatt-hour, against a Washington, D.C. retail rate assumed at 18.0¢.
How much does it cost to install solar panels in Washington, D.C.?
Installation is not priced separately — the $2.70–$3.55 per watt above is a turnkey figure covering panels, inverter, racking, labor, permitting and interconnection. What moves it most in DC is roof complexity, whether the main panel needs upgrading, and whether a battery is included. Expect a site visit to change any online estimate, including this one.
How much do solar panels cost in Washington, D.C.?
Using an assumed installed cost of $2.70–$3.55 per watt, a typical 8 kW home system in Washington, D.C. costs roughly $21,600–$28,400 before incentives. Smaller and larger systems scale roughly with size, though small systems cost more per watt.
Is solar worth it in Washington, D.C.?
With Washington, D.C. electricity around $0.18/kWh and production around 1,300 kWh per installed kW per year, an 8 kW system could save roughly $1,543 in year one, for a simple payback of about 14–18 years with no federal credit. Whether that is "worth it" depends on your rate plan, export compensation, roof, and how long you plan to stay in the home.
How many solar panels do I need in Washington, D.C.?
It depends on your electricity usage, not your roof. At Washington, D.C.'s assumed 1,300 kWh per installed kW, a 6 kW system (about 15 panels at 425 watts) generates roughly 7,800 kWh a year, and a 10 kW system (about 24 panels) roughly 13,000 kWh. Compare that against your annual kWh from a utility bill — our calculator sizes it from your monthly bill in about a minute.
Does Washington, D.C. have net metering?
The District requires full retail net metering with credits that roll over indefinitely.
What solar incentives does Washington, D.C. offer in 2026?
D.C. SRECs have traded in the hundreds of dollars per MWh — a typical home system can earn thousands per year — and Solar for All serves income-qualified households. Verify current SREC prices. Note that the federal Section 25D residential credit ended for systems installed after December 31, 2025, so state, local and utility programs are now the main incentives for purchased systems.
Is there still a federal solar tax credit in Washington, D.C.?
No — the 30% federal residential clean energy credit (Section 25D) ended for systems installed after December 31, 2025 under the One Big Beautiful Bill Act. Leased or PPA systems may still benefit indirectly because the system owner can claim the commercial 48E credit through 2027.
Use this as a starting point
This page provides broad state assumptions, not a current market survey or binding quote. Before purchasing, verify applicable incentives, utility rules, installer licensing, warranties and financing terms.
Where these numbers come from
State assumptions are informed by public data and reviewed periodically (September 2026):