Formula Used
Direct current: Power watts = Voltage × Current.
Single phase: Power watts = Voltage × Current × Power factor.
Three phase: Power watts = √3 × Line voltage × Current × Power factor.
Energy: kWh = Watts × Seconds ÷ 3,600,000.
The calculator also applies quantity, duty cycle, and efficiency. Cost equals kWh multiplied by tariff. Emissions equal kWh multiplied by the emission factor.
How to Use This Calculator
- Select direct current, single phase, or three phase.
- Enter voltage, current, and operating time in seconds.
- Add power factor for alternating current loads.
- Enter efficiency, duty cycle, quantity, tariff, and emissions factor.
- Press calculate to view kWh, watts, cost, and emissions.
- Use CSV or PDF download options for reporting.
Example Data Table
| System | Voltage | Current | Seconds | Power Factor | Power | Energy |
|---|---|---|---|---|---|---|
| Direct Current | 12 V | 5 A | 60 | 1.00 | 60 W | 0.001000 kWh |
| Single Phase AC | 230 V | 10 A | 120 | 0.92 | 2116 W | 0.070533 kWh |
| Three Phase AC | 400 V | 16 A | 300 | 0.85 | 9422.3 W | 0.785192 kWh |
About This Electrical Energy Calculator
This tool helps estimate energy use from voltage, current, and time in seconds. It is useful when a device runs for short intervals. Many meters show power in watts. Many bills show energy in kilowatt-hours. This calculator links both ideas in one place.
The form supports direct current, single phase alternating current, and three phase alternating current. You can enter power factor for alternating current loads. You can also adjust duty cycle, efficiency, quantity, tariff, and emissions factor. These options make the result more practical for workshops, labs, pumps, chargers, heaters, motors, and field tests.
Why Seconds Matter
Some electrical tests are short. A relay may run for ten seconds. A motor may start for a few seconds. A heater may pulse many times each hour. Using seconds avoids rough hour estimates. It also helps compare small energy events with large monthly totals.
The calculator first finds real power. For direct current, power is voltage multiplied by current. For alternating current, power factor adjusts the real working power. For three phase systems, the square root of three is used with line voltage and line current. The final energy is found by multiplying watts by seconds and then dividing by 3,600,000.
Practical Planning Value
A small kWh number can still matter. Repeated events can add up across many machines. The cost result shows how each run affects a bill. The emissions estimate gives a quick environmental view. The watt-hour and kilojoule values help technical users compare batteries, heat, and mechanical work.
Use accurate readings for best results. Measure voltage under load when possible. Use true RMS meters for alternating current. Enter the correct power factor for motors, transformers, and electronic supplies. If power factor is unknown, use a conservative estimate. Review the example table before running your own case. Then export the CSV or PDF report for records, audits, or client notes. Keep assumptions visible when sharing calculated reports.
This calculator is an estimator. It does not replace certified metering. Wiring condition, harmonics, voltage drop, waveform shape, and meter accuracy can change real results. Still, it gives a clear starting point. It makes quick energy math easier, especially when time is measured in seconds.
FAQs
1. How do I calculate kWh from voltage and current per second?
Find watts first. Multiply voltage by current. Add power factor for alternating current. Then multiply watts by seconds and divide by 3,600,000. The result is kilowatt-hours.
2. Why is 3,600,000 used in the formula?
One kilowatt-hour equals 1,000 watts used for 3,600 seconds. That equals 3,600,000 watt-seconds. Dividing watt-seconds by 3,600,000 converts the result into kWh.
3. Should I use power factor for direct current?
No. Direct current normally uses voltage multiplied by current. The calculator uses a power factor of 1 for direct current, even when another value is entered.
4. Which voltage should I enter for three phase systems?
Enter line-to-line voltage for the three phase option. The calculator then applies the square root of three with current and power factor.
5. What does duty cycle mean?
Duty cycle is the percentage of time the load is active during the entered period. Use 100 for continuous operation. Use lower values for pulsed or intermittent loads.
6. Why does efficiency change the energy result?
Efficiency adjusts the useful or delivered energy estimate. A lower efficiency means less useful output from the same apparent electrical input. Use 100 when losses are unknown.
7. Can this calculator estimate electricity cost?
Yes. Enter your tariff per kWh. The calculator multiplies energy in kWh by that tariff. The result is an estimated running cost for the entered seconds.
8. Is this calculator suitable for official billing?
No. It is an estimator for planning and comparison. Official billing needs certified metering. Real systems may vary because of waveform quality, harmonics, meter accuracy, and voltage changes.