Estimate solar system cost by size and price per watt, before and after the 30% federal tax credit.
Estimate only. Prices, sun hours and rates vary by location and installer.
We multiply system size (in watts) by your cost per watt for the gross price, then apply the 30% federal tax credit for your net cost.
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Solar is quoted per watt installed — multiply by your system size for the gross price, then subtract the 30% federal tax credit. An 8 kW system at $3/watt is $24,000 gross, about $16,800 after the credit. Cost per watt is the number to compare across installers; anything well above $3.50 deserves scrutiny.
Often $2.50–$3.50 per watt installed; an 8 kW system runs ~$20,000–28,000 before the credit.
The federal residential clean energy credit cuts 30% off your system cost on your taxes.
Yes — quotes are usually all-in per watt.
No — get local installer bids.