⚡ WattCosts

Solar Savings Calculator

What rooftop solar would actually save you — sized from your bill, priced at 2026 installed costs, and honest about the expired federal tax credit.

Estimate

Your yearly usage (from the bill)
System size needed
Estimated installed cost
First-year savings
Simple payback
25-year net savings (flat rates)

Assumptions kept deliberately simple and visible: production stays constant (panels actually degrade ~0.25–0.5%/yr), electricity rates stay flat (they have mostly risen), full retail credit for exported power (true under 1:1 net metering; California NEM 3.0 and some other states credit exports at much less). No federal tax credit is applied — the residential credit (25D) expired December 31, 2025. State incentives, where they exist, improve these numbers.

How this is calculated

Yearly usage = bill × 12 ÷ rate. System size (kW) = usage × offset ÷ production factor. Installed cost = size × $/W. First-year savings = offset share of your yearly bill. Simple payback = cost ÷ yearly savings. The production factor bundles your local sun, panel orientation, and shading into one number — a real installer quote replaces it with a site-specific simulation.

The 2026 reality check

Most solar calculators online still assume the 30% federal tax credit. It's gone for purchased systems — Section 25D expired at the end of 2025 — which lengthened typical paybacks by several years overnight. What still helps: falling hardware prices (US average ≈ $2.58/W installed in 2026), state-level rebates and property-tax exemptions, net metering where preserved, and lease/PPA arrangements where the financing company claims the commercial-side credit (Section 48E) and shares part of it as lower payments. The result: solar in 2026 is a genuinely good deal in high-rate, high-sun states and a marginal one elsewhere — which is exactly what the calculator above will tell you.

FAQ

Is there still a federal solar tax credit in 2026?

Not for systems you buy — the 30% residential credit (Section 25D) expired December 31, 2025. Leased/PPA systems can still benefit indirectly via the commercial credit (48E). Many states kept their own rebates and net-metering programs.

Is solar still worth it without the credit?

It depends almost entirely on your rate and sun. At 30¢+/kWh, payback is often 6–10 years even without the credit; at 13¢/kWh with average sun it can exceed 15 years. That's why this calculator asks for your actual bill and state.

How many panels is that?

Divide the system size by ~0.4 kW per panel: a 6 kW system is roughly 15 modern panels, needing about 30 m² (330 ft²) of unshaded roof.

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