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Will solar actually save you money?

Estimate system size, cost, payback, and 25-year return before you talk to an installer. The result is a planning estimate, not a quote.

Your home details

Use your bill and replace the planning defaults with current figures where possible.

No email required No sales calls Editable assumptions
Your estimate
Why bother? Because knowing your ballpark numbers before talking to installers means you won't get oversold a system that's too big - or overpay for one that's right-sized.
System size - kW Estimated solar array
Gross install cost - Before any incentives
Net cost after entered credit - Defaults to 0%; verify eligibility
Annual savings - Year 1 electricity savings
Payback period - Years to break even
25-year ROI - Estimated total return

Ready to compare real quotes?

Use the state guide to identify the tariff, incentive and utility questions that belong beside this estimate.

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Editorial guide. No quote request or personal details required.

Transparency

How the calculator works

The assumptions are shown so the estimate can be checked and adjusted rather than treated as a black box.

System size

Monthly electricity consumption is estimated from your bill and the electricity rate shown in the form. State selection supplies a planning default and a peak-sun assumption informed by US EIA data and NREL PVWatts. Replace the rate with the figure on your bill.

Install cost

The installed cost per watt is editable and should be replaced with a current local cash quote. A visible multiplier is applied for non-standard roof types. Any tax credit is entered by the user and defaults to zero because eligibility and current law must be verified.

Annual savings

The estimate assumes the system offsets 90% of annual electricity consumption. Savings use the selected state electricity rate and a 3% annual escalator.

25-year ROI

Net cost after the tax-credit percentage entered in the form is subtracted from cumulative savings over 25 years. The credit defaults to zero. Savings are escalated at 3%/year for electricity inflation and reduced at 0.5%/year for panel degradation; both assumptions are disclosed planning inputs, not forecasts.

Important: These are estimates only. A proper site assessment will account for roof orientation, shading, local permitting costs, and utility-specific net metering policies. Use these numbers to gut-check installer quotes - not as a final answer.