Solar panel payback in Delaware

12.5 years for a typical home solar system in Delaware to pay for itself, with no federal tax credit.

A 9.0 kW system sized for the average home here, which uses 929 kWh a month, costs about $25,200 at $2.80 per watt. It saves about $1,879 in its first year, and after 25 years it is $37,224 ahead. That is slow. The system still ends up ahead, but a higher quote or a shaded roof could erase most of the gain.

Prices updated October 2026 from EIA, AAA and BLS data.

Your state

Electricity price

¢/kWh

Monthly electricity use

kWh

System size

Installed cost

$/W

2026 quotes average $2.60 to $3.00.

State and local incentives

Rebates or state tax credits.

Export credit

% of retail

Output, rate increases and upkeep

Yearly output per kW

kWh/kW

Output used as it is made

The rest goes to the grid. Higher if you are home by day.

Yearly electricity price rise

U.S. prices rose 5% in the past year.

Panel output loss per year

Inverter replacement in year 12

Set to 0 if your inverter warranty runs 25 years.

How Delaware compares

Delaware ranks 19th of 51 for solar payback, fastest first. The fastest is Hawaii at 5.9 years. At U.S. average figures, payback is 12.3 years.

Two things set payback: what each kWh is worth and how many the panels make. Delaware ranks 19th for electricity price, most expensive first, at 18.48¢/kWh, and 27th for sunshine, at an estimated 1,300 kWh a year per kW of panels. Expensive power does the work here; sunshine is below the U.S. average of 1,350 kWh per kW.

The calculator assumes power sent to the grid earns 75% of the retail price, typical of net metering. Your utility's tariff sets the real rate, and a lower credit slows payback.

Every neighboring state pays back faster, led by New Jersey at 8.9 years.

State	Electricity	Sun, kWh/kW	Payback
New Jersey	25.19¢	1,300	8.9 yrs
Maryland	21.41¢	1,300	10.2 yrs
Pennsylvania	21.72¢	1,250	10.5 yrs
Delaware	18.48¢	1,300	12.5 yrs

More for Delaware

EV charging cost in Delaware vs gas: an EV saves $1,078 a year on fuel.
Heat pump vs gas in Delaware: a heat pump saves $23 a year.

What these numbers assume

A 9.0 kW system, sized to cover about 100% of a typical home's yearly use.
$2.80 per watt installed, paid in cash, with no state or local incentives entered.
No federal tax credit: Section 25D ended for systems placed in service after December 31, 2025.
Half the output used in the home as it is made; the rest credited at 75% of the retail price.
Electricity prices rising 3% a year, panels losing 0.5% of output a year, and a $2,000 inverter replacement in year 12.

Change any of them in the calculator above to match your own bills. The formulas are on the main solar payback calculator.

Sources

Electricity price: EIA Electric Power Monthly, Table 5.6.A (July 2026 data).
Household use: EIA 2025 retail sales divided by customers.
Installed cost: 2026 residential marketplace averages.
Output per kW: MeterMath estimate for a south-facing fixed roof system, rounded.
Export credit: MeterMath assumption for typical net metering.
Tax credit status: Public Law 119-21.