The short version
- Cash has the lowest lifetime cost and the longest wait to break even.
- A loan keeps ownership — and therefore any tax credit — while spreading the cost, at the price of interest.
- Leases and PPAs mean no upfront cost, no ownership, and no tax credit for you.
- Selling the house is where third-party-owned systems get complicated. Ask about transfer terms before signing, not when you list.
The four structures
| Cash | Loan | Lease | PPA | |
|---|---|---|---|---|
| Upfront cost | Full | $0 – low | $0 typically | $0 typically |
| You own the system | Yes | Yes | No | No |
| Tax credit goes to | You | You | The lessor | The provider |
| You pay for | — | Loan repayments | Fixed monthly rent | Power produced, per kWh |
| Maintenance | You | You | Provider | Provider |
| Lifetime cost | Lowest | Middle | Higher | Higher |
Cash
The cheapest way to own solar, and the one that makes the payback calculation simplest: no interest, no escalator, no third party. You carry the maintenance responsibility and you claim any incentives you qualify for.
The real question is not whether cash is cheapest — it is — but whether that capital is better deployed elsewhere. Compare the effective return of the solar system against what the same money would do in your other options. For many households solar competes well; for some it does not.
Solar loan
You own the system, so you keep the incentives, and you spread the cost. The trap is the dealer fee: many advertised low-rate solar loans carry an origination fee, often a substantial percentage of the amount financed, folded into the price rather than shown separately.
Three things to check on any solar loan:
- The cash price versus the financed price. If the financed price is higher, the difference is the fee. Ask for both.
- Whether the payment schedule assumes you apply a tax credit as a lump sum. Many do, and the payment jumps if you don't — which matters a lot if the credit turns out smaller than assumed, or unavailable.
- Whether it is secured against your home. Some are. That changes the risk profile entirely.
A home equity loan or line of credit is sometimes cheaper than a branded solar loan for the same reason: no dealer fee. Worth pricing both.
Lease and PPA
A lease rents you the equipment for a fixed monthly payment. A PPA sells you the power the system produces at an agreed price per kWh. In both, a third party owns the array, claims the incentives, and handles maintenance.
The appeal is genuine: no capital outlay, no maintenance responsibility, immediate savings if the payment is below your old bill. For a household with little tax liability — where an ownership credit would be worth little anyway — the gap narrows considerably.
The terms that decide whether it is a good deal:
- The escalator. Many agreements raise the payment annually, often 1–3%. Over 20 years a 3% escalator nearly doubles the payment. If your utility rates rise more slowly than that, your savings shrink year over year and can invert.
- Term length. Typically 20–25 years. That is a long commitment attached to your roof.
- Production guarantee. What happens if the system underproduces? Is there compensation, or just an estimate that was optimistic?
- End of term. Do you buy it, renew, or have it removed — and at whose cost?
What happens when you sell
This is the part that gets skipped in the sales conversation and matters enormously later.
- Owned system (cash or loan). It is part of the house. It generally supports resale value, because the buyer inherits lower running costs. A loan secured against the property is normally settled at closing like any other lien.
- Leased or PPA system. The agreement has to be transferred to the buyer, who must qualify and agree to take it on — or you buy the contract out, sometimes for a significant sum. Buyers who don't want it can walk. Agents in high-solar markets will tell you this delays deals.
If there is any chance you will move within the term, read the transfer clause before you sign, and ask what a buyout would cost at year five and year ten.
Choosing
- Have capital and tax liability?Cash usually wins on lifetime cost, with a loan close behind if you would rather keep the capital.
- Want ownership without the outlay?A loan — but price the dealer fee, and compare against home equity borrowing.
- Little or no tax liability, and want it simple?A lease or PPA becomes more competitive, since the credit was worth less to you anyway. Scrutinise the escalator.
- Moving within a few years?Think hard before any 20-year agreement attached to a house you plan to sell.