Energy Units, Cost and Payback

These calculators turn power and price into energy and money. Convert watts and hours to kWh, convert between MWh and kWh, price a device’s electricity, and judge a solar purchase by payback period or loan payment.

Tools in this group

• Electricity Cost Calculator (kWh) — Enter the watts, the hours of use and your price per kWh to see what an appliance costs to run, or enter a bill to find your price per kWh.
• kWh Calculator (Watts to Kilowatt-Hours) — Enter the power of a device and how long it runs to get the energy in kWh and Wh per day, month and year.
• MWh to kWh Conversion (Energy Unit Converter) — Enter an amount of energy and pick the units to convert between MWh, kWh and other energy units.
• Solar Loan Calculator — Enter the system cost, down payment, interest rate and term to see the monthly payment and total interest.
• Solar Payback Calculator — Enter the system cost, size and your electricity price to find the payback time and the savings year by year.