This calculator works out motor energy from horsepower, efficiency and run time. Horsepower is converted to mechanical output and divided by efficiency to estimate electrical input, unless a known input-watt value is used. Replace the example values with information from your own label, bill, drawing, product sheet or land record. Check the motor plate, pump efficiency and real daily run time; borewell head and water demand affect operation. The formula and every editable assumption remain visible so the result can be checked before it is used for planning. Keep the values and result together when you compare or share this planning scenario.
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Every input includes a simple explanation.
Private: calculations run in your browser. Saved scenarios, preferred electricity rate and land state stay on this device.
Use these as formula demonstrations only. Confirm the motor plate, input mode, efficiency and actual run time for your own installation.
| Example | Input basis | Monthly energy | Monthly cost | Yearly cost |
|---|---|---|---|---|
| 0.5 hp · 30 min/day | 0.5 hp ÷ 80% × 0.5 h/day | ₹55.95 | ₹55.95 | ₹671.40 |
| 1 hp · 1 hour/day | 1 hp ÷ 80% × 1 h/day | ₹223.80 | ₹223.80 | ₹2,685.60 |
| 2 hp · 2 hours/day | 2 hp ÷ 80% × 2 h/day | ₹895.20 | ₹895.20 | ₹10,742.40 |
Horsepower describes mechanical output; grid input also includes motor losses.
Efficiency must be replaced when the motor plate or manufacturer provides it.
Actual run time depends on water demand, storage and pump controls.
After finding running energy, separately plan the motor's starting surge for backup equipment.
These examples answer the calculation first without pretending every pump has the same input power. Replace horsepower, efficiency and runtime with the motor plate and operating record for your installation.
| Example | Inputs | Visible working | Answer |
|---|---|---|---|
| 0.5 hp · 30 min/day | 0.5 hp, 80% efficiency, 30 days | 0.5 × 746 ÷ 0.80 × 0.5 × 30 ÷ 1,000 | 6.99 kWh/month |
| 1 hp · 1 hour/day | 1 hp, 80% efficiency, 30 days | 1 × 746 ÷ 0.80 × 1 × 30 ÷ 1,000 | 27.98 kWh/month |
| 2 hp · 2 hours/day | 2 hp, 80% efficiency, 30 days | 2 × 746 ÷ 0.80 × 2 × 30 ÷ 1,000 | 111.90 kWh/month |
Rated power can be different from average power while the appliance is running.
Voltage, automatic on-off cycling and equipment condition can change real use.
Use this as a budget estimate. The appliance label, how often it runs and all charges on your tariff determine the real bill.
Read the meaning first, verify the important details, then avoid the most common planning error.
Horsepower is converted to mechanical output and divided by efficiency to estimate electrical input, unless a known input-watt value is used.
Check the motor plate, pump efficiency and real daily run time; borewell head and water demand affect operation.
Treating 1 hp as exactly 746 W from the grid ignores motor losses and can understate billed energy.
Updated 19 August 2026. Changes listed here describe this calculator release; they are not invented historical entries.