Energy Efficiency Calculator
Estimate electricity usage, operating costs, efficiency ratings, carbon emissions, and potential savings for any appliance, home, or business — instantly, with no sign-up required.
Results
Visual Indicators
Interactive Charts
Rendered live with HTML5 Canvas — no external chart libraries.
Standard vs. Energy-Efficient Comparison
| Metric | Standard Appliance | Energy-Efficient Appliance |
|---|
Energy Saving Tips
Personalized recommendations based on common efficiency gaps.
Replacing incandescent bulbs with LEDs cuts lighting energy use by roughly 75–85%.
Use smart plugs or power strips to cut phantom loads from idle electronics.
Certified models typically use 10–50% less energy than standard equivalents.
Sealing attics and walls reduces heating and cooling loads significantly.
Automatic setbacks can save 8–15% on heating and cooling costs annually.
Setting your water heater to 120°F reduces standby heat loss and cost.
Weatherstripping doors and windows prevents conditioned air from escaping.
Offsetting grid consumption with solar can reduce long-term electricity bills.
Automate on/off schedules for devices that don't need to run continuously.
Modern high-SEER systems can cut cooling costs by 20–40%.
Engineering Formulas
The exact equations used by this calculator, with worked examples.
Energy (kWh)
Example: A 1,500 W space heater run for 3 hours uses 1,500 × 3 ÷ 1000 = 4.5 kWh.
Electricity Cost
Example: 4.5 kWh × $0.16/kWh = $0.72 for that session.
Annual Consumption
Example: A device using 1.2 kWh/day consumes 1.2 × 365 = 438 kWh/year.
CO₂ Emissions
Example: 438 kWh × 0.855 lb/kWh ≈ 374 lb CO₂/year.
Efficiency Percentage
Example: A motor delivering 850 W of useful work from 1,000 W input is 85% efficient.