⚡ Quick: jump to your motor size
5 HP 7.5 HP 10 HP 15 HP 20 HP 25 HP or use the custom calculator below ↓
⚡ Energy Cost

Motor Running Cost Calculator

Calculate exactly how much electricity your motor consumes — per hour, day, month and year.

⚠️ Most factories underestimate motor costs. A single 10 HP motor running double shift can cost over ₹2.5 lakh/year in electricity. If you have 20–30 motors on the floor, that's ₹50–75 lakh/year — often untracked until the bill arrives.
Enter motor nameplate kW rating
1 HP = 0.746 kW
Typical: 75–85% for industrial motors
IE2: 88–92% | IE3: 91–95%
Industrial tariff in India: typically ₹6–12 per kWh
📊 Running Cost Breakdown
Actual Power Draw
—
Cost per Hour
—
Cost per Day
—
Cost per Month
—
⚡ Annual Electricity Cost
—
Monthly Energy Consumption
—
Formula Used:
Actual Power (kW) = Rated kW × Load% ÷ Efficiency%
Cost = Actual Power × Hours × Tariff (₹/kWh)
💡 IE3 Upgrade Saving: Replacing a standard IE1 motor with IE3 (premium efficiency) can cut running cost by 5–8%. At this consumption, that's roughly —/month saved — payback in 12–24 months on most motor sizes.

How This Calculator Works

Estimates electricity cost based on rated power, actual load, motor efficiency and your tariff. Most motors don't run at nameplate rating — load factor and efficiency are the two factors that make the real difference.

Load Factor: A 7.5 kW motor driving a pump at 80% load actually draws about 6 kW of mechanical power.

Motor Efficiency: An IE2 motor at 90% efficiency means 10% of input electricity is lost as heat — so actual electrical draw is higher than mechanical output.

Calculate for Your Specific Motor Size

Pre-populated calculators with worked examples for the most common HP sizes:

HPkWTypical Use
5 HP →3.7 kWSmall pumps, fans
7.5 HP →5.5 kWMedium pumps, compressors
10 HP →7.5 kWCompressors, conveyors
15 HP →11 kWLarge pumps, mixing tanks
20 HP →15 kWBig compressors, blowers
25 HP →18.5 kWHeavy industrial drives

💰 Related Cost Calculators

⛽ Diesel Generator Running Cost 🔧 Compressed Air Cost ⚡ Electricity Cost Calculator 💧 Pump Power Calculator 🏭 Motor Energy Cost 🔄 HP to kW Converter

📘 Related Guides

Motor Running Cost Formula

The electricity cost of running a motor depends on three things: how much power it actually draws, how many hours it runs, and your electricity tariff. The nameplate kW is a starting point — load factor and efficiency are what give you the accurate number.

Actual Power (kW) = Rated kW × (Load Factor ÷ 100) ÷ (Efficiency ÷ 100) Energy per Day (kWh) = Actual Power × Hours per Day Cost per Day (₹) = Energy per Day × Tariff (₹/kWh) Cost per Month (₹) = Cost per Day × Working Days Cost per Year (₹) = Cost per Month × 12

Worked Example — 10 HP Motor

Motor: 10 HP = 7.5 kW  |  Load: 80%  |  Efficiency: 90%  |  Hours: 8/day  |  Days: 26/month  |  Tariff: ₹8/kWh

Actual Power = 7.5 × 0.80 ÷ 0.90 = 6.67 kW
Daily Energy = 6.67 × 8 = 53.3 kWh/day
Monthly Cost = 53.3 × 26 × ₹8 = ₹11,093/month
Annual Cost = ₹11,093 × 12 = ₹1,33,120/year

How to Reduce Motor Running Cost

  • Install Variable Frequency Drives (VFDs) on pumps and fans — saves 20–50% on variable-load motors
  • Upgrade to IE3 or IE4 premium efficiency motors — payback is typically 1–3 years
  • Ensure motors are correctly sized — an oversized motor running at 40% load wastes significantly more energy
  • Schedule motor operation during off-peak tariff hours where time-of-day pricing exists
  • Regular bearing and winding maintenance prevents efficiency loss over time
  • Consider power factor correction — poor PF increases kVA demand charges on your electricity bill

Common Motor Running Cost Reference Table

Monthly electricity cost at ₹8/kWh, 80% load factor, 90% efficiency, 26 working days/month.

Motor Size 8 hrs/day 12 hrs/day 16 hrs/day 24 hrs/day
1 HP (0.75 kW)₹1,109₹1,664₹2,219₹3,328
2 HP (1.5 kW)₹2,219₹3,328₹4,437₹6,656
5 HP (3.73 kW)₹5,530₹8,295₹11,059₹16,589
7.5 HP (5.6 kW)₹8,296₹12,443₹16,591₹24,886
10 HP (7.5 kW)₹11,093₹16,640₹22,186₹33,280
20 HP (15 kW)₹22,186₹33,280₹44,373₹66,560
30 HP (22.4 kW)₹33,165₹49,747₹66,330₹99,494
50 HP (37.3 kW)₹55,275₹82,912₹1,10,550₹1,65,825
100 HP (74.6 kW)₹1,10,549₹1,65,824₹2,21,099₹3,31,648

* Approximate values. Use the calculator above for exact figures with your specific load and efficiency values.

Frequently Asked Questions

Use the formula: Actual Power (kW) = Rated kW × Load Factor% ÷ Efficiency%. Then: Cost = Actual Power × Hours × Tariff (₹/kWh). For example, a 7.5 kW motor at 80% load, 90% efficiency, 8 hrs/day at ₹8/kWh: Actual Power = 7.5 × 0.80 ÷ 0.90 = 6.67 kW. Daily cost = 6.67 × 8 × 8 = ₹427. Always use actual load factor, not nameplate rating alone.

A 10 HP (7.5 kW) motor running 8 hours/day for 26 days/month at 80% load, 90% efficiency and ₹8/kWh tariff costs approximately ₹11,093/month. Running double shift (16 hrs/day), that rises to around ₹22,186/month — or ₹2.66 lakh/year. Use the calculator above with your exact tariff and operating hours for a precise figure.

Load factor is the percentage of the motor's rated power it actually uses in operation. A 10 kW motor driving a pump at 70% of capacity runs at 70% load factor. Most industrial motors operate between 70–85% load. Calculating cost using nameplate kW (100% load) overestimates actual electricity consumption by 15–30%.

IE ratings are international efficiency classes for electric motors. IE1 (standard) is the least efficient at 80–87%. IE2 (high efficiency) reaches 86–92%. IE3 (premium efficiency) is 89–95%. IE4 (super premium) exceeds 95%. Most older Indian factory motors are IE1. Upgrading to IE3 reduces electricity consumption by 3–8%, which typically pays back in 1–3 years on continuously running motors.

The most impactful methods are: (1) VFDs on pumps and fans — saves 20–50% on variable-load motors, (2) Upgrading to IE3/IE4 motors, (3) Correct motor sizing — oversized motors at low load are inefficient, (4) Scheduling heavy loads in off-peak tariff hours, (5) Power factor correction to reduce kVA demand charges, and (6) Regular maintenance to prevent winding and bearing losses.

A 5 HP (3.73 kW) motor running 24 hours/day at 80% load, 90% efficiency and ₹8/kWh tariff: Actual power = 3.73 × 0.80 ÷ 0.90 = 3.32 kW. Daily cost = 3.32 × 24 × 8 = ₹636/day. Monthly cost (30 days) = ₹19,085/month. Annual cost = ₹2,29,018/year. For a single-shift 8-hour operation, the monthly cost is approximately ₹5,530.

📦 Embed this calculator on your site

Free for any blog, forum or LinkedIn post. Copy this snippet and paste it where you want the calculator to appear. Attribution to Anedya Enterprise is included automatically.

↗ Preview
Paste anywhere — the iframe auto-detects context and renders in compact embed mode with the Powered-by Anedya Enterprise attribution.