Water Motor Electricity Cost Calculator
Water motors and pumps run daily in most Pakistani homes. Enter your motor size, daily running hours and electricity tariff to find out how many units it uses per month, what it costs you monthly and yearly, and the cost per hour of running.
Cost across tariff slabs (same usage)
| Tariff Slab | Rate (Rs/unit) | Monthly Units | Monthly Cost |
|---|
How to use
- Select your motor size (0.5, 1, 1.5 or 2 HP) or choose custom wattage and enter the watts from the motor rating plate.
- Enter average daily running hours and how many days per month the motor runs.
- Set the motor loading percentage (80% default) and your tariff per unit, or use a quick-pick slab.
- Click Calculate Cost to see monthly units, monthly and yearly cost, cost per hour, the slab comparison table and saving tips.
How the estimate is calculated
Motor HP is converted to watts using 1 HP = 746 watts. Effective power draw equals rated watts multiplied by the loading percentage. Daily units (kWh) equal effective watts divided by 1000, multiplied by daily running hours. Monthly units equal daily units times days per month. Cost is units multiplied by your tariff in Rs per unit. Yearly cost equals monthly cost times 12.
Note: this is an estimate. Actual consumption depends on voltage fluctuations, motor age and condition, actual loading, and the exact tariff slabs and taxes on your electricity bill.
Frequently Asked Questions (FAQ)
How is the water motor electricity cost calculated?
Motor size in HP is converted to watts using 1 HP = 746 watts, then multiplied by the loading percentage to get effective watts. Daily units equal effective watts divided by 1000, multiplied by daily running hours. Monthly units equal daily units times days per month. Cost is units multiplied by your electricity tariff in Rs per unit.
How many units does a 1 HP water motor use in one hour?
A 1 HP motor is rated at 746 watts, so at full load it uses about 0.75 units (kWh) per hour. With the default 80 percent loading used by this calculator, it uses about 0.6 units per hour. Enter your own tariff to see the cost per hour for your motor.
Why does the calculator ask for motor loading percentage?
A water motor rarely draws its full rated power all the time. Actual draw depends on pump condition, pipe length and how hard the motor works. The default of 80 percent gives a realistic estimate; set it lower for an oversized motor that runs lightly, or 100 percent for a heavily loaded motor.
What does the slab comparison table show?
The table shows your monthly cost at the same motor usage across four sample tariff slabs: 1-100 units, 101-200 units, 201-300 units, and 301+ units. It helps you see how the monthly cost changes as your tariff slab changes. Sample rates are used because official slabs change; check your own electricity bill for your exact rate.
How accurate is the estimate?
It is an estimate, not an exact bill figure. Actual consumption varies with voltage fluctuations, motor age and condition, actual loading, and the exact tariff slabs and taxes on your bill. Use the custom wattage and custom tariff fields to get the closest result.