Solar and Energy Calculators
Estimate solar savings, system size, and household energy costs.
Number of Calculators: 6
- Solar Panel SavingsEstimate your solar panel payback period and lifetime savings from your system cost and electric bill.
- Electricity CostEstimate your monthly and yearly electricity cost from your usage in kWh and your rate per kWh.
- Voltage DropCalculate how much voltage is lost over a wire run based on its gauge, length, material, and current.
- Ohm's LawSolve for voltage, current, or resistance from the other two using Ohm's Law, plus the resulting power.
- Solar Panel System SizeEstimate the solar system size (in kW) and number of panels needed to offset your electricity usage.
- Solar CO2 SavingsEstimate the CO2 emissions your solar system avoids each year, using the EPA's own greenhouse gas equivalencies.
Guided Journeys
Some of these calculators are also part of a guided journey — a connected chain that carries your numbers forward automatically. A journey may include steps from other categories too.
Solar Savings Journey
Start Journey →Before you can tell whether solar panels are worth it, you need to know what you're actually paying for electricity today, how big a system would even cover that usage, and what payback period that system offers. This journey starts by estimating your current monthly bill from your usage and rate, carries that same usage figure into a system-size estimate (how many kW and panels you'd need), then carries the resulting bill total into the solar payback calculator so you get a real payback period without having to dig up a utility bill or size a system yourself.
- Estimate Your Current Electric Bill
- See What Size System You Need
- See Your Solar Payback Period