Electricity Calculator
Calculate electrical power consumption, energy costs, and efficiency. Determine electricity bills, power usage, and energy savings for your home or business.
Power & Usage Settings
Common Appliances
Typical Electricity Rates
Electricity Cost Analysis
Cost Breakdown
Energy Consumption
Environmental Impact (Annual)
Energy Saving Tips
How to Use the Electricity Calculator
To calculate your electricity costs accurately:
- Enter the power rating of your appliance or device
- Specify how many hours per day and days per week it operates
- Input your electricity rate from your utility bill
- Adjust the efficiency factor if needed (100% for most appliances)
- Click "Calculate" to see detailed cost and energy consumption analysis
- Use the preset buttons for common appliances and typical rates
Calculation Methods
Energy Consumption Formula
Energy (kWh) = Power (kW) × Hours of Use × Efficiency Factor
Cost Calculation
Cost = Energy Consumption (kWh) × Electricity Rate ($/kWh)
Power Conversion
- Watts to Kilowatts: Divide by 1,000
- Horsepower to Watts: Multiply by 746
Environmental Impact
CO₂ emissions are calculated using an average grid emission factor of 0.5 kg CO₂ per kWh, which varies by region and energy source mix.
Example: Air Conditioner Cost
Given: 3,000W air conditioner, 8 hours/day, 7 days/week, $0.12/kWh
Calculation:
- Daily Energy: 3 kW × 8 hours = 24 kWh/day
- Daily Cost: 24 kWh × $0.12 = $2.88/day
- Monthly Cost: $2.88 × 30 days = $86.40/month
- Annual Cost: $2.88 × 365 days = $1,051.20/year
Result: Running this air conditioner costs approximately $86.40 per month during peak usage.
Frequently Asked Questions
How do I find my electricity rate?
Check your electricity bill for the rate per kWh. It's usually listed as "Energy Charge" or "Supply Charge." Rates vary by location, time of use, and consumption tiers.
What affects appliance efficiency?
Age, maintenance, and type of appliance affect efficiency. Motors and transformers typically operate at 80-95% efficiency, while resistive loads (heaters, incandescent bulbs) are nearly 100% efficient.
How can I reduce my electricity bill?
Use energy-efficient appliances, adjust thermostat settings, unplug devices when not in use, switch to LED lighting, and consider time-of-use rates to shift usage to off-peak hours.