Solar financial feasibility analysis that shows its assumptions

What a solar financial feasibility analysis answers

A solar financial feasibility analysis answers one question with care: what is this decision worth to you, in dollars, over its life? A good one shows the base case, the realistic range around it, and the one or two assumptions doing most of the work. A sales proposal shows a single number. We show the number and how it was built, on an assumptions page you can check line by line.

This discipline covers homes, businesses, farms and public bodies, and it doesn’t change based on who’s paying for the panels. Our fee doesn’t depend on whether you buy.

The questions this discipline answers

• What will this cost over its life, including financing, inverter replacement and roof timing?
• What is each kilowatt-hour worth under my actual tariff, used on-site versus exported?
• How do a lease, a PPA, a loan and a cash purchase compare over the same years?
• What happens to the answer if rates rise more slowly than the proposal assumes?
• For a business: what does a missed federal credit deadline do to the return?
• For a battery: what is backup power, time-shifting or demand reduction actually worth here?

The assumption that moves the answer most

Here’s an illustrative example. A system saves $1,500 in its first year and loses half a percent of output each year. If electricity prices rise 2% a year, 25 years of savings add up to about $45,000. At 5% a year, the same system “saves” about $66,600. That’s a $21,600 difference from one assumption, before anyone has looked at the panels.

A proposal that assumes 5% isn’t necessarily wrong. It’s making a choice, and you deserve to see that choice and what happens if it doesn’t come true. Our rate stress-testing guide shows the method.

Why the math changed in Kentucky in 2026

• No federal credit for homeowner-owned systems. The residential clean energy credit ended for expenditures after December 31, 2025.
• Two prices per kilowatt-hour. Newer net metering customers of KU and LG&E receive export credits of $0.07534 and $0.07089 per kWh, kept at those levels in the PSC’s 2026 rate-case orders. Power you use on-site avoids the full retail energy charge, so the share you consume yourself drives the value.
• Higher rates. LG&E and KU rates rose in January 2026 under the PSC’s rate-case decision, which raises the value of every kilowatt-hour you don’t buy.
• A commercial deadline. Under the 2025 federal budget law, solar projects that didn’t begin construction by July 4, 2026 generally must be placed in service by the end of 2027 to claim the business credits. Sourcing restrictions also apply to projects beginning construction after 2025. Confirm eligibility with your tax adviser.
• Storage on its own clock. Battery credits for business owners follow a different, longer schedule than solar.

How the three services differ

Service	Best for	Core question	Timeline
Proposal Second Opinion	Homes and single buildings with a quote	Is this proposal fair, and do its numbers hold up?	5 business days
Commercial Feasibility Study	Businesses, manufacturers, public bodies	Does on-site solar work under our tariff, load and deadlines?	3–5 weeks
Battery & Storage Economics	Anyone considering storage	What is a battery worth here, and from which source?	7–10 business days

If you’re comparing ownership options on your own first, try our lease, PPA, loan or cash comparison tool. To see what our reports look like, browse the sample reports.

Where this discipline stops

We build independent financial estimates for evaluation by you and your qualified advisers. We don’t give tax, legal or investment advice, and we don’t arrange financing. When a number depends on tax treatment, such as depreciation or credit eligibility, we write it down as a question for your CPA and model the scenarios they confirm.