By house size

How many panels a home of a given floor area needs. A rough proxy — your bill is the better input.

By electric bill

The better question: how much solar it takes to offset what you actually pay each month.

By system size

What a system of a given size costs, covers and produces.


Planning figures at 400 W per panel, 1,400 kWh per kW per year and $2.50–$3.50 per watt. Your own state will differ.

Get the number for your actual roof

A free, no-obligation estimate based on your address and bill. Under a minute.

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