Solar Calculator

Solar Calculator

Calculate how much power you need with these solar calculators to estimate the size and the cost of the solar panel array needed for your home energy usage. Ideally, you will know your total kilo-watt hours (kWh) used for the past 12 months or the average monthly kWh used each month. Check your electric bills or contact your local utility for your kWh used.The cost and size of a solar panel system depends on your current and future energy consumption, your location, the types of solar panels and components to be installed, and the availability of rebates and incentives.

Monthly Electric Bill Estimate

Actual Energy Use Quote

Select your monthly electric bill for a general online estimate of how much solar power your need

Use this Solar Calculator to determine a precise system size for your actual energy use. Refer to the definitions below for explanation.

1. Your kWh used per year: kWh/year[?]
2. Solar Hours per Day (see map below):
3. % of Electricity Bill to Offset: %
Solar Array Size Estimate: kW [?]

4. Estimated Cost per Watt [?]
Solar Array Cost Estimate: $

Find Solar Kits

Once you know how many kilowatts kW you need, choose your size to see solar kits for sale at SunWatts. These pre-engineered systems qualify for tax credits and rebates. We can also custom design a solar system just for you!



Solar Power Map of the United States

Find your Solar Hours per Day using the color-coding on this map. Enter the value for your location into the solar calculator.

solar-radiation-map of the USA

The solar map uses insolation, a measure of solar radiation energy received on a given surface area in a given time. This is typically measured in kilo-watt hours per square meter per day (kWh/m2/day). The map shows the average daily total solar radiation throughout the United States. The U.S. Department of Energy, National Renewable Energy Laboratory (NREL) developed it.