Solar Panel Calculator for United States

Rooftop solar is mainstream across the United States, helped by the 30% federal tax credit and rising utility rates. This free solar calculator estimates your system size, payback period, ROI and savings in dollars using your local electricity rate and sun hours.

Calculate my solar payback in United States →

Solar at a glance in United States

With the 30% credit and rising utility bills, payback commonly lands in the 7–12 year range, then years of free electricity over a 25-year warranty.

CurrencyUS dollars (USD)
Typical electricity rate$ 0 per kWh
Installed cost≈ $ 3 per watt
Peak sun hours≈ 4.7 hours/day
Rooftop subsidy / credit≈ 30% (indicative)
Export / buyback≈ $ 0 per kWh

Indicative 2026 starting points — every figure is editable in the calculator, and results depend on your own bill, roof and installer quotes.

A typical 5 kW system in United States

At around $ 3 per watt, a 5 kW rooftop system costs roughly $ 12,500 and produces about 6,690 kWh in its first year at United States's 4.7 peak sun hours a day. Your real numbers depend on your roof, shading, panel choice and how much power you use during the day — run your own figures in the calculator to see your exact payback, net savings and ROI.

How the solar calculator works

  1. Your setup. United States and US dollars are pre-selected, with local electricity rate, install cost and sun hours filled in. Enter your monthly bill, or size the system from your appliances.
  2. Your roof. Search your address or tap “use my location”, then draw your roof on the satellite map — or just type its area. We check the system fits and read local sun hours from NASA data.
  3. Your results. Instantly see your payback period, net savings, ROI, system size, year-1 production and lifetime CO₂ offset — compare cash vs. a loan, and download a PDF report.

Common questions — solar in United States

How many solar panels do I need in United States?

It depends on your electricity use, roof space and local sun hours (about 4.7 peak sun hours/day here). A 5 kW system of high-wattage panels is a common starting point for a home — enter your bill or appliances and the calculator gives your exact panel count and system size.

Does United States have net metering?

Net metering rules are set state by state and utility by utility. Many states still offer full retail net metering; others (notably California under NEM 3.0) have moved to lower net-billing export rates, which favours pairing solar with a battery.

Are there solar subsidies or incentives in United States?

The federal Residential Clean Energy Credit covers 30% of system cost (in effect through 2032 under current law), and many states, utilities and municipalities add their own rebates. Enter your combined incentive percentage in the calculator.

How much does a solar system cost in the United States?

A typical 5 kW system is around $ 12,500 before incentives at about $ 3 per watt installed; after the 30% federal credit your net cost drops. Enter your rebate to see the net figure.

Is solar worth it in the US?

For most homeowners with a decent roof and the 30% credit, yes — you offset a rising utility bill and the system pays for itself well within its warranty. Enter your bill to check.

Work out your system size

Not sure how big a system you need? These guides work back from your monthly usage:

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