Free tools
US home energy calculators
Updated for 2026. The federal credits for buying solar, batteries, EVs and home chargers have ended, so every calculator here starts from your state's real electricity price and shows its sources.
Calculators
- NewSolar lease vs buy calculatorCompare cash, loan and lease over the same years, including dealer fees and lease escalators.Open calculator →
- NewBattery backup calculatorPick the appliances you need in an outage and see how many batteries, how long they last and the cost.Open calculator →
- UpdatedSolar calculatorSystem size, installed cost and payback from your bill, for the US, Germany, India and the UK.Open calculator →
- UpdatedHome battery (BESS) calculatorBattery size, cost and payback for solar self-consumption, backup or time-of-use savings.Open calculator →
What changed for US households
Most online calculators still subtract a 30% federal credit. For systems installed in 2026 that credit no longer applies to homeowners who buy.
Where the numbers come from
- Federal credit for buying solar or a battery (25D)
- None for systems installed after December 31, 2025IRS FAQs on Public Law 119-21 · checked Oct 27, 2026
- Leased or PPA systems (48E, claimed by the provider)
- Provider may claim it; for most new solar leases the system must be in service by December 31, 202726 U.S.C. §48E(e)(4) and §48E(i) · checked Oct 27, 2026
- Federal credit for a new or used EV (30D / 25E)
- None for vehicles acquired after September 30, 2025IRS FAQs on Public Law 119-21 · checked Oct 27, 2026
- Federal credit for a home EV charger (30C)
- None for chargers placed in service after June 30, 2026IRS FAQs on Public Law 119-21 · checked Oct 27, 2026
Each calculator lists its defaults with a source and a check date. Change any input to match your own quote or bill.