Energy Calculators
Explore our collection of free calculators designed to help you make smarter energy decisions and save money.
Solar Payback
Calculate how many years it will take for energy savings to equal the initial cost of your solar panel system.
Battery Storage
Size home battery systems, estimate backup duration, and calculate savings from solar self-consumption and time-of-use arbitrage.
Bill Estimator
Calculate your monthly electricity bill based on appliance usage with support for flat and tiered rate structures.
Water Heater
Compare operating costs between tankless, heat pump, and traditional tank water heaters for your household.
HVAC Sizing
Calculate the right size heating and cooling system for your home based on square footage, climate, and insulation.
Carbon Footprint
Estimate your annual CO2 emissions from electricity, gas, driving, and flights, with tips to reduce your impact.
Pool Energy
Estimate energy costs for pool pumps, heaters, and hot tubs with savings tips for variable-speed pumps and solar covers.
Insulation ROI
Calculate the return on investment for insulation upgrades with payback periods and 10-year savings projections.
Smart Thermostat
Estimate savings from upgrading to a smart thermostat based on your HVAC costs, occupancy patterns, and current thermostat.
EV Charging
Estimate your electric vehicle charging costs at home or public stations and compare to gas costs.
Appliance Payback
Determine how long it takes for a new energy-efficient appliance to pay for itself through utility savings.
Vampire Load
Estimate the annual energy cost and waste from electronics that draw phantom power when switched off.
Heat Pump vs Furnace
Compare operating costs between heat pumps and traditional furnaces for your climate and home.
Lighting Retrofit
Calculate energy savings and payback period when upgrading to LED lighting from fluorescent or HID.
Motor Torque/HP
Convert between electric motor horsepower, torque, and RPM for performance analysis.
Space vs Central Heat
Calculate which heating method costs less for your situation—space heaters or central heating.
Generator Sizing
Determine the right generator size for your home or business based on your essential loads.
Steam Pipe Loss
Calculate heat loss from uninsulated steam pipes and potential savings from adding insulation.
Solar Sizing
Calculate the right solar panel system size based on your electricity usage, roof space, and energy offset goals.
Wire Gauge
Calculate the proper wire gauge for electrical circuits based on current, distance, and acceptable voltage drop.
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