Home

Home Energy Calculators

Most expensive home-energy mistakes happen before the purchase: a battery that is too small, a charger your panel cannot handle, a thermostat that takes years to pay off. Start with the Whole-Home Energy Calculator to see how your whole setup adds up. When you want to go deeper on one piece, the quick checks below answer one question in more detail, then point you to the products I have reviewed that actually fit.

Start here · All 7 categoriesWhole-Home Energy CalculatorWhat does your whole smart home setup add up to?Mix gadgets from every category and see the electricity your setup adds or saves, the net change on your monthly bill, how long your backup battery keeps the essentials on, and how much solar can refill it.Try the calculator →
ThermostatsEnergy MonitorsSmart EV ChargersSmart PanelsBattery BackupSmart PlugsSolar Panels

Quick checks

Single-question calculators that go deeper on one gadget.

Battery BackupHow big a backup battery do you need?Tick what has to stay on during an outage and see the kWh you need, plus the power stations that fit.Try the calculator →Smart EV ChargersCan your panel handle an EV charger?Check how fast a charger your electrical panel can likely support before you buy one.Try the calculator →ThermostatsHow fast would a smart thermostat pay for itself?Plug in your bill and see your payback time, plus the thermostat that fits your home.Try the calculator →

Each tool uses conservative, published assumptions and shows its math. They are a starting point, not a substitute for an electrician or installer quote.