Is solar worth it? Payback in every state

How the payback is worked out

Each state is priced on the cheapest plan open to any household from its largest utility modeled on HomeWattCost (the state’s average price where no utility is modeled), with the same engine as the solar payback calculator:

• Production: hour by hour from PVWatts (NLR, formerly NREL) for a south-facing roof at the state’s center of population, losing 0.5% a year as panels age.
• Use: the state’s typical home, hour by hour, so the model knows how much solar is used as it is produced and how much is exported.
• Price: $4.0 per watt installed, the 2024 US median before incentives (Berkeley Lab), so $28,000 for 7 kW. No federal tax credit: the residential credit ended for systems installed after 2025.
• Savings: the bill on the plan with and without solar, rising each year at the state’s average price rise over the last ten years (EIA).

The export rule decides what the power you send to the grid is worth, and it varies by utility and by year of connection. So every state is shown under two rules that bound the answer: full net metering, where each exported kWh offsets a kWh bought at the plan’s own prices, and no export credit, where only the solar you use as it is produced saves anything. Most real rules fall between the two.

Sunshine matters less than the price

A kW of panels produces 1,831 kWh a year in Nevada and 912 in Alaska, 2.0 times as much. The average price of electricity differs more: from 12.3¢ a kWh in North Dakota to 44.3¢ in Hawaii, 3.6 times as much (EIA, last 12 months). What a solar kWh saves is the price it replaces, so the fastest paybacks under net metering are in Hawaii, Massachusetts, New York, California, while sunny states with cheap power, or with plans whose midday hours are cheap, pay back slowly. In Nevada, even full net metering does not pay the system back within 25 years at this price.

Net metering, though, is not what new customers get everywhere. In Hawaii: net metering closed to new customers in October 2015. In California: net billing for new customers since April 15, 2023. For a new system there, the answer lies between the two columns of the table, with exports credited below the retail price.

The export rule

In the typical home modeled here, a median 49% of a 7 kW system’s output is used in the house as it is produced; the rest is exported, mostly around midday when the house uses little. Under net metering those exports are worth the retail price; with no credit they are worth nothing, and the first-year saving falls from a median $1,445 to $795. With no export credit the system does not pay back within 25 years in 21 of the 51 states. Some states have replaced net metering for new customers with lower export credits, so check the rule your utility applies today; the utility’s solar or interconnection page states it. The Utility Rate Database records an export rule for 20 of the plans below.

What changes the answer for your home

• Your price per watt. Berkeley Lab found the middle 60% of 2024 home systems cost between $3.0 and $5.2 per watt; every quote is different, and the payback scales roughly with it.
• Rebates and credits. State and utility incentives, where they exist, come straight off the price.
• Your plan. On a time-of-use plan, solar saves the price of the hours it produces, often off-peak; on a tiered plan it removes the dearest kWh first. The calculator prices both.
• Your roof and your use. Shade, orientation and a home that uses more at midday all change how much is produced and how much is used directly.

Not included: batteries, financing costs, inverter replacement, maintenance, and any change to your plan’s fixed or minimum charges for solar customers. The methodology describes how plans and the typical home are modeled; see also is a time-of-use plan worth it?