Solar Lease vs Buy vs PPA on Long Island — Which Math Actually Works

Four options, not two

The "lease vs buy" framing on a solar proposal is usually too simple. On Long Island in 2026 there are really four common paths: cash purchase, $0-down solar loan, solar lease, and PPA (power purchase agreement). Each shifts ownership, incentive flow, and bill-savings math in different ways — and the right answer depends on your tax situation, your time horizon in the home, and how you want to think about the system.

Long Island Solar Installation Pros provides solar installation help — we are not a licensed installer and we do not sell financing products. This guide walks through how each path actually works so you can read what an installer's proposal is showing you.

Cash purchase — usually the cleanest math

You pay for the system outright (or via a separate home equity loan / HELOC at your own bank). You own the equipment. You keep every active state and federal incentive directly — including the New York State 25% residential solar equipment credit (capped at $5,000) and any active federal residential program at the time of installation.

Federal residential incentives have changed — the IRS Residential Clean Energy Credit applied to qualified property installed from 2022 through December 31, 2025 and is not available for property placed in service after that date. The NY State 25% credit remains active and works the same way regardless of how the system is financed. The cash math typically produces the shortest payback period and the highest lifetime savings — at the cost of the upfront capital.

When cash works best: homeowners with the available capital, sufficient NY State tax liability to use the credit (or the willingness to use the five-year carryforward), and a multi-year time horizon in the home.

$0-down solar loan — the most common product, with fine print

You sign a loan that finances the full system cost. You own the equipment (the loan is collateralized by the system, not your home, in most products). The loan is amortized over a long term (often 25 years). Many $0-down products include a reamortization clause: the loan assumes a percentage of the principal will be paid down within ~18 months via the federal tax credit, and the monthly payment after that reamortization point is calculated assuming the credit was applied.

This is where 2026 matters: pre-existing $0-down loan structures often assumed the IRS Residential Clean Energy Credit would apply. For projects placed in service after December 31, 2025, that credit is not available. If the loan reamortization assumed the credit and the credit does not exist, the monthly payment after month 18 may not match what the original proposal quoted.

Also watch for the dealer fee. Solar loans typically include a dealer fee built into the system price — often 15–25%+ of the cash-equivalent. It is real money, and it is usually disclosed if you ask directly.

When $0-down loans work best: homeowners with stable income who want predictable monthly payments and either (a) confirm a federal credit is in force at the time of install, or (b) accept the post-reamortization payment as a possibility.

Solar lease — you do not own the system

The leasing company owns the equipment. You pay a fixed monthly lease payment (sometimes with an escalator clause that raises the payment over time). The leasing company keeps any active state and federal tax incentives and most other tax benefits. Your savings come from a guaranteed lower electric bill, not from owning the system.

Leases can work for homeowners who do not have New York State tax liability to use the NY credit, who do not want to handle the capital outlay, and who want a single fixed monthly number. They typically produce lower lifetime savings than cash or loan purchases, but they do not require capital or tax-credit-friendly income.

Read leases carefully: the escalator clause (does the monthly payment go up over time?), the term length, what happens if you sell the home before the lease ends, and who handles warranty service. Lease transfers at home sale are a real issue — buyers sometimes ask for them to be paid off, which can affect the sale price.

PPA (power purchase agreement) — buy the kilowatt-hours, not the system

A PPA is similar to a lease in that you do not own the system. The difference is that instead of paying a fixed monthly lease payment, you pay a per-kWh rate for the electricity the system produces (the developer-owner keeps the incentives, you get a guaranteed rate, often with an escalator). If the system produces less than expected, you pay less.

PPAs are more common on commercial installations than residential on Long Island, but they exist for residential. The math is similar to a lease: lower lifetime savings than ownership models, but no capital outlay and no incentive-eligibility requirements on the homeowner side.

Which one for which home

You have the capital and tax liability to use the NY credit, and you want to maximize lifetime savings: cash purchase.

You want predictable monthly payments and either qualify for the NY credit or accept the federal-sunset risk on $0-down reamortization: $0-down loan, with the loan reamortization clause confirmed in writing.

You do not have NY State tax liability or do not want the capital risk: lease or PPA, with the escalator clause and transfer terms confirmed.

You plan to sell the home within a few years: cash or loan. Leases and PPAs introduce transfer friction that can complicate a sale.

Incentives change and eligibility varies — confirm details with the program administrator and a qualified tax professional. This is not tax advice.