About Solar Straight
The problem this was built for
Search for a solar calculator and almost every result is a lead-generation business. The calculator is the bait. You type in your address, you get an encouraging number, and the form asks for your phone number to "send your full report". That contact detail is the actual product: it is sold to installers, often several at once, and the calls start the same day.
Two things follow from that business model. The estimate has to be optimistic, because a realistic one produces fewer leads. And you cannot see the workings, because a visible assumption is an assumption you might argue with.
This site sells nothing and collects nothing, so it has no reason to flatter the answer. Sometimes it tells you solar will never pay for itself where you live. That is a real result and you deserve it before you spend an evening with a salesperson.
What makes the numbers different
The largest single difference is the federal tax credit. The 30% Residential Clean Energy Credit ended for home purchases after 31 December 2025, and a great many calculators and sales scripts still apply it. On a typical system that is around $7,800 of imaginary money and roughly three years of imaginary payback.
The second is exported power. Assume every surplus kilowatt-hour earns full retail and a too-large system looks sensible. Net metering is being rolled back across the US, so this calculator values exports at zero and counts only the electricity you would have bought anyway.
The third is that roofs have a size limit. Sizing purely from a bill can conclude you need 25 kW of panels. That is not a recommendation, it is the model running past physical reality, and the calculator says so.
The full workings are on the methodology page, including the assumptions that could make the estimate wrong.
Who built it
Sastihari S, software engineer & builder. I build calculators and analysis tools, most of which exist because I wanted an honest answer to something and could not find one that was not attached to a sales funnel.
I am not a solar installer. I do not sell panels, take commission, or have any relationship with a company that does. I have no financial interest in your answer being yes.
I am also not a licensed financial or tax adviser, and nothing here is personal financial advice. See the disclaimer.
How it stays free
Running costs are small: the underlying data comes from free US government APIs and hosting a site like this is inexpensive. The intended support is ordinary display advertising, which does not require knowing who you are.
Your inputs are used to calculate your result and are not stored, sold or passed to installers. There is no account, no newsletter and no follow-up. See privacy.
Corrections
If a number here looks wrong, tell me and I will check it. Tax law and net metering rules change, sometimes abruptly - the federal credit ending is exactly that kind of change. Being told about an error is more useful to me than being right.
Last updated 2026-08-20.