Free Solar Energy Calculators
Estimate your savings, payback period, and solar output — instant results for your location.
- No signup
- No email capture
- Instant results
- Independent data
Solar Savings Calculator
Adjust any input — savings, payback, and the 25-year chart update in real time.
Your inputs
Cumulative Savings Over 25 Years
Skip ahead to the question you came for
Three of the most-used solar calculators, one click away.
All Solar Calculators
11 free tools covering savings, cost, payback, ROI, sizing, tax credit, batteries, EV charging, and more.
Solar Panel Savings Calculator
Estimate how much you could save with solar panels based on your monthly electricity bill and location.
OpenSolar Installation Cost Estimator
Estimate the gross cost, federal tax credit, and net cost of installing solar panels at your home.
OpenSolar Payback Period Calculator
Calculate how many years it will take for your solar system to pay for itself.
OpenSolar Panel System Size Calculator
Calculate the right solar system size, number of panels, and roof area based on your monthly electricity usage.
OpenSolar Tax Credit Calculator
Calculate the federal Investment Tax Credit (ITC) value for your solar system, including any battery storage.
OpenSolar ROI Calculator
Calculate the 25-year return on investment, net present value, and yearly returns from your solar installation.
OpenSolar Loan vs Cash vs Lease Comparison
Compare the 25-year total cost of paying cash, financing with a loan, or leasing a solar system.
OpenSolar Battery Storage Calculator
Calculate the payback period and value of adding battery storage to your solar system.
OpenSolar + EV Charging Calculator
Calculate how much you save by charging your EV with solar power instead of fueling a gas car.
OpenNet Metering Savings Calculator
Calculate your annual net metering credit value based on monthly solar production and home consumption.
OpenSolar Panel Output by Location
Estimate annual and monthly solar production for your system size based on your state's peak sun hours.
OpenHome Energy Calculators
Understand and shrink your existing electricity bill — heat pump vs furnace, appliance costs, and a whole-home energy audit.
Electricity Cost Calculator
Calculate your monthly and annual electricity costs based on your usage and state's average rate.
Home Energy Audit Calculator
Estimate your annual home energy costs by category and identify the biggest savings opportunities.
Heat Pump vs Furnace Cost Comparison
Compare the operating cost of a heat pump vs. a fossil-fuel furnace over 15 years.
Home Appliance Energy Cost Calculator
Calculate the monthly and annual energy cost of common household appliances based on your electricity rate.
Authoritative data, transparent math, zero sales agenda
We do not sell solar, do not capture leads, and do not partner with specific installers. The goal is a neutral first answer you can test against real quotes.
Free, no signup
All calculators run locally in your browser. No email captures, no follow-up sales.
Neutral, not a funnel
We are not a solar installer. Calculators give you a starting point, not a quote.
Authoritative sources
Rates from EIA · sun hours from NREL · tax credit rates from the IRS and DOE.
Clear answers to a $15,000–$40,000 question
What Solar Energy Calcs is, how we source our numbers, and why we built it this way.
Solar & Home Energy Calculators is an independent calculator-first resource for homeowners researching solar panels and home energy efficiency. Every calculator runs entirely in your browser with no signup, no sales pitch, and no personal information required.
We pull our reference data from the U.S. Energy Information Administration (EIA), the National Renewable Energy Laboratory (NREL), and the Department of Energy. Federal tax credit values are based on the current Internal Revenue Code under the Inflation Reduction Act.
All our calculators give you instant estimates as you adjust the inputs — no submit buttons, no waiting. Use them to compare scenarios, stress-test assumptions, and decide whether the next step (getting installer quotes) is worth your time.
Frequently asked questions about our calculators
Common questions about data sources, accuracy, and what to do with the estimates.