About GreenEnergyCalc
Free, accurate calculators for solar panels, EVs, battery storage and home energy — built for homeowners who want real numbers, not a sales pitch.
Why we built this
GreenEnergyCalc exists because we couldn't find a single good, free, unbiased calculator for solar panels that didn't try to sell us something.
Every tool we found was either buried behind a lead-generation form, produced wildly optimistic numbers to get us to request a quote, or was so simplified it was useless for real decision-making. So we built our own.
What we offer
34 free calculators covering solar savings, payback period, ROI, EV vs gas costs, home battery storage, heat pump savings, federal tax credits and more. Every calculator uses real electricity rate data, actual sun hours by state, and current incentive information from official sources including the EIA, NREL and IRS.
Our principles
- No lead generation. We never ask for your contact details or sell your information to solar installers.
- No inflated numbers. Our calculators use conservative, documented assumptions — and explain every variable.
- Free, always. Every calculator on this site is free to use, no signup required.
- Transparent methodology. We show exactly how every calculation works so you can verify it yourself.
- No advertising influence. We do not accept payment for editorial coverage. Raptive display ads fund the site — they have no influence on calculator results or article content.
Our team
Mark covers residential solar economics, federal clean energy incentives and EV total cost of ownership. He holds a B.S. in Mechanical Engineering (University of Michigan) and a Certified Energy Auditor credential. Before joining GreenEnergyCalc, he spent four years as an analyst at a Midwest regional utility evaluating distributed energy resource programmes.
View full bio and articles →Supporting research, data updates and calculator accuracy reviews. Our editorial contributors include energy industry researchers, utility finance analysts and clean technology writers with combined experience spanning solar installation economics, EV fleet management and US clean energy policy.
Editorial policy
All calculator tools and articles are produced independently. We do not accept sponsored content, paid placements or affiliate commissions from solar installers, EV manufacturers or energy companies.
Tax-related and incentive content is cross-referenced against current IRS guidelines, DSIRE and official state programme documentation before publication. This content is intended for informational purposes only and does not constitute tax, financial or professional advice. Readers should consult a licensed tax professional for their specific situation.
Data sources used across the site include the U.S. Energy Information Administration (EIA), National Renewable Energy Laboratory (NREL), Solar Energy Industries Association (SEIA), IRS publication guidelines and the Database of State Incentives for Renewables & Efficiency (DSIRE). Where data changes, we update affected pages and revise the lastmod date in each article.