Savings and payback

Savings calculator at 5% rate inflation

See your complete year-by-year savings table at 5% annual rate inflation, a higher-growth scenario above the historical average, from year one through year 25.

Current status: the 30% federal residential solar tax credit (Section 25D) expired for systems placed in service after December 31, 2025. If you're buying with cash or a loan in 2026 or later, use your full system price with no credit subtracted. Only subtract 30% if your system was placed in service by the end of 2025.

Your numbers

1 Starting savings and cost
Use the result from the solar savings calculator if needed.
Add this to also see your break-even year and total return multiple at 5% growth. 0% federal credit is the accurate default for a new purchase in 2026 or later; use 30% off only if your system was placed in service by 12/31/2025.

How it works

One input, the full table

Step 1

Enter your year one savings

Use the result from the solar savings calculator as your starting point.

Step 2

Get every year at 5%, instantly

This locks in a higher-growth scenario and shows every year from 1 through 25. Compare against the 3% scenario to see the difference a higher rate makes.

Step 3

Add your system cost for break-even and return

Optionally enter your net system cost to also see the exact year you break even at 5% growth, plus your total return as a multiple of what you paid. The US Department of Energy's homeowner's guide to going solar walks through the same decision step by step.

Understanding the 5% scenario

When to reach for a 5% assumption

Use 5% if you're in a region that has recently seen faster-than-average rate increases, or if you want to stress-test your savings projection against a more aggressive but still plausible scenario. It sits meaningfully above the 2 to 3% historical US average, making it a useful upside case rather than a default expectation. Utility rates drive the whole savings calculation, and the US Energy Information Administration's electricity data track them state by state.

What the full table shows

Starting at $1,800 in year one, annual savings grow to about $2,792 by year 10 and $5,805 by year 25, more than tripling the starting figure. The cumulative 25 year total comes to about $85,909, compared to $65,627 at the 3% scenario shown on the 3% rate inflation calculator, a difference of roughly $20,282. If you have not sized the system yet, start with the system size by annual kwh usage and bring its kilowatt figure back here.

How aggressive is 5%, really

It's on the higher end of plausible. Historical US averages run closer to 2 to 3%, so 5% represents a genuine upside scenario rather than a typical expectation. It's most useful for understanding the range your savings could fall into rather than as your primary planning figure.

Seeing the full picture across scenarios

Check the 7% rate inflation calculator for an even more aggressive case, or the rate increase sensitivity calculator to see all the scenarios side by side against the same starting figure. The production figure behind this estimate comes from the real world vs nameplate output gap calculator, which models output for your location and roof.

Questions

Frequently asked

Use 5% if you're in a region that has recently seen faster-than-average rate increases, or if you want to stress-test your savings projection against a more aggressive but still plausible scenario. It sits above the 2 to 3% historical US average.

Starting from $1,800 in year one, the 5% scenario totals about $85,909 over 25 years, compared to $65,627 at 3%, a difference of roughly $20,282 for the same starting figure.

Annual savings grow from $1,800 in year one to about $2,792 by year 10 and $5,805 by year 25, more than tripling the starting figure by the end of the period.

It's on the higher end of plausible. Historical US averages run closer to 2 to 3%, so 5% represents a genuine upside scenario rather than a typical expectation, useful for understanding your range rather than as a primary planning figure.

Related tools

Keep exploring rate scenarios

Savings at 3% rate inflation Savings at 7% rate inflation Rate increase sensitivity Rate inflation projection tool Cumulative savings graph generator Year by year savings breakdown Lifetime savings, 25 year All savings and payback tools