About Energy Payoff
A free set of home energy calculators, written because the ones already out there were quietly wrong.
Why this site exists
Ask the internet whether home solar is worth it and you get a payback period. Almost every one of those numbers still subtracts a 30 percent federal tax credit. That credit, Section 25D, ended on December 31, 2025 under the One Big Beautiful Bill. There was no phase down and no transition period. A household that installs solar in 2026 gets nothing.
A calculator that still applies it shortens the payback by roughly three years. That is not a rounding error. It is the difference between an upgrade that pays for itself while you still live in the house and one that does not. Every tool here uses the rules as they actually are, and says so on the page.
Where the numbers come from
Electricity prices are residential averages by state. Solar output is the annual energy a kilowatt of panels produces in that state, which is mostly a question of sunshine and roof angle. Installed cost per watt starts at the national average and you can move it, because the only cost that matters is the one on your own quote.
These are state averages, not your street. Two houses in the same city can differ by a third depending on roof shade, orientation and which utility bills them. Treat every figure here as the shape of the answer, then get a written quote for the answer itself.
What this site does not do
It does not ask for your phone number, it does not pass your details to an installer, and it does not sell leads. Nothing you type is sent anywhere - the math runs inside your own browser, which is why the numbers change as you type rather than after a wait.
The site carries advertising. That is the whole business model, and it is the reason the tools can stay free and unregistered.
What is here
There are five tools now: solar, home EV charging against gasoline, heat pumps against gas, oil, propane and baseboard, attic insulation, and what individual appliances cost to run for a year. All of them ask the same question - what does this cost, what does it save, and when does it break even - and all of them answer it with your own state rather than a national average.
Two of them say something the industry would rather they did not. A heat pump loses to cheap natural gas in cold states, and the federal credits that paid for solar, heat pumps and insulation all ended on December 31, 2025. Nothing here subtracts money that no longer exists.
Contact
Corrections are welcome, particularly on state figures. Write to hello@energypayoff.com or use the contact page.