Payback if you move or sell before the system pays for itself

The two-clock worksheet

Step 1: unrecovered cost at sale equals net system cost minus cumulative savings up to the sale year. Use your own valued savings (with the export haircut from the calculation guide), not a brochure figure. Step 2: compare that unrecovered balance with what an owned, paid-off system plausibly adds to a sale in your market, using the evidence below as a range to test, not a promise. Step 3: decide whether the gap is a price you accept for the years of savings and the roof decision itself, or a reason to choose a smaller system, a different structure, or to wait. If the system is financed, the loan balance at sale replaces part of this math: a buyer rarely assumes a loan, so the payoff at closing comes out of your proceeds, and the structure guide covers how leases and PPAs compare, and the leased-solar sale guide walks the transfer, buyout and fixture-filing steps a sale triggers.

Worked example: selling in year four

Use the California illustration from the calculation guide: a $23,600 system saving $3,965 a year when all production is valued at the retail price. After four years the savings clock has recovered 4 times $3,965, which is $15,859, leaving an unrecovered balance of $23,600 minus $15,859, which is $7,741. Under the haircut version of the same system ($2,775 a year), four years recover $11,100 and the unrecovered balance is $12,500. The sale question is therefore concrete: would an owned 8 kW system, four years old with its production records and warranty paperwork in hand, plausibly add something in the $7,700 to $12,500 range to this home sale? The evidence below says premiums in that range have been observed for smaller systems in older data; it does not say your buyer will pay it.

What the sales evidence actually says

The most cited evidence is the Lawrence Berkeley National Laboratory multi-state study of roughly 22,000 home sales from 2002 to 2013, about 4,000 of them with solar. It found that homes with owned photovoltaic systems sold at a premium, averaging roughly $4 per installed watt, or about $15,000 for the typical 3.6 kW system in that dataset. Read the limits before you use the number: the sales are from 2002 to 2013, when systems were smaller and scarcer; the premium is an average across markets that varied; and the study measures what buyers paid then, not what a buyer will pay for your system, on your street, in your year. The honest use of the study is as a plausibility check on the worksheet, not as a second savings figure to add into payback. Appraisers have formal methods for valuing solar in a sale; a generic premium per watt is not one of them.

Each study behind that number, what it counted, how fast the premium fell as systems aged, and how lenders treat owned, financed and leased panels are read one by one in the home value evidence guide.

Making the sale clock work in your favor

Buyers and appraisers discount what they cannot verify, so the paperwork is the lever you control. Keep the contract and proof the system is owned and paid off, the production history from your monitoring app, the panel and inverter warranty documents and their transfer terms, and the utility interconnection agreement. A leased or PPA system transfers a contract rather than conveying an asset, and transfer terms, buyer qualification, and escalators become negotiation points that an owned system does not raise; if a move within the contract term is likely, weigh that friction before choosing a structure, using the lease, buy, or PPA guide. Timing also matters: a premium, where one exists, attaches to a working system with remaining warranty, so a sale in year four with records is a different proposition from a sale in year nineteen without them.

Frequently asked questions

Should I skip solar if I might move in five years?

Run the worksheet first. In a high-price state the savings clock alone can recover a large share of the cost in five years, and the unrecovered balance may be small enough that even a modest premium, or none, leaves the decision close. In a low-price state with a long payback, the same move is a stronger argument for a smaller system or for waiting.

Can I add the expected premium into my payback calculation?

Keep it out of the headline payback. A premium is uncertain, market-dependent, and only realized at sale, while bill savings are contractual arithmetic. Present the two clocks side by side, as this page does, and let the gap inform the decision.

What if the system is leased?

Then there is usually no asset to sell and no premium to claim; the buyer is asked to take over the remaining contract. Transfer fees, credit checks, and escalator terms decide how much friction that adds, and they are in your agreement, not in any study.

Sources

Lawrence Berkeley National Laboratory, Selling into the Sun and related photovoltaic home premium research: a multi-state analysis of roughly 22,000 sales from 2002 to 2013 (about 4,000 with solar), finding an average premium near $4 per watt, about $15,000 for a typical 3.6 kW system in the dataset. Worked example arithmetic is this site illustration, verified by calculation on October 15, 2026, using the EIA California price and production midpoint from the checked state record. Page checked October 15, 2026.

Next: payback by state and solar tax credit status.