1. What is an Energy Usage Calculator?

Definition: This calculator estimates the energy consumption in kilowatt-hours (kWh) based on power consumption in watts and usage time in hours.

Purpose: It helps homeowners, businesses, and energy-conscious individuals understand and monitor their electricity usage.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( E \) — Energy in kilowatt-hours (kWh)
• \( P \) — Power consumption in watts (W)
• \( t \) — Time in hours (h)

Explanation: The formula converts watt-hours to kilowatt-hours by dividing by 1000 (since 1 kWh = 1000 Wh).

3. Importance of Energy Calculation

Details: Understanding energy usage helps in budgeting electricity costs, comparing appliance efficiency, and reducing carbon footprint.

4. Using the Calculator

Tips: Enter the device's power consumption in watts and the duration of use in hours. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: How do I find my appliance's power consumption?
A: Check the label on the appliance or its manual. Many devices list power in watts.

Q2: What if my device shows amps instead of watts?
A: Multiply amps by voltage (usually 120V in US) to get watts (P = I × V).

Q3: How can I estimate monthly energy costs?
A: Multiply kWh result by your electricity rate (found on your utility bill).

Q4: What's a typical kWh usage for household appliances?
A: Refrigerators use about 1-2 kWh/day, LED bulbs 0.01 kWh/hour, AC units 3-5 kWh/hour.

Q5: Why divide by 1000 in the formula?
A: Utility companies bill by kilowatt-hours (1000 watt-hours), making it a standard unit.