CaSolarHow to compare price per watt
Divide the solar-only cash price by the DC capacity of the panels in watts. A $20,000 solar-only quote for 8 kW DC is $2.50 per watt. If a second quote is $26,500 for 8.4 kW DC and includes a separately priced $5,500 battery, its solar-only portion is $21,000 and also works out to $2.50 per watt. These prices illustrate the calculation.
If storage or non-solar work is bundled without a separate price, ask the installer for an itemized total. Even when two quotes have the same price per watt, their warranties, equipment and included work can differ.
Request an itemized quote
You can copy this note into an email to an installer of your choice.
Could you send a written cash quote before incentives, with the panel count and DC system size? Please list the battery, main-panel upgrade and roof work separately, and say which circuits the battery can back up. Please include the utility rate and battery mode used for the first-year savings estimate. If you offer financing, please include the full payment schedule and total of payments.