How much electricity does an energy efficient oil expeller save in a mustard oil mill?
About 7.4 kW for every hour it runs. BEE's Alwar report replaces a 60 HP expeller with a 50 HP energy efficient one of the same 48 by 8 inch size, saving 22,200 kWh over 3,000 hours a year. That is 15 t CO2 on today's grid, not the report's 20 t. Payback about 3.4 years.
Old against new, as BEE measured them
- Old expeller: 60 HP rated, 48 by 8 inch, drawing up to 40 kW at full feed.
- New expeller: same size, 50 HP rated, expected to draw up to 32.5 kW.
- What changes: double reduction gearing, a better gearbox and bearings, and an energy efficient motor. The report puts the gain at 5 to 10 percentage points of efficiency.
- Run: 10 hours a day, 300 days a year.
The money
- Saving: 10 HP, 7.4 kW, x 3,000 hours = 22,200 kWh a year. The report's annexure uses the measured 40 to 32.5 kW, 7.5 kW, which gives 22,500.
- At Rs 4.8 a kWh: Rs 1.07 lakh a year.
- Cost: Rs 2.92 lakh for the expeller, Rs 0.37 lakh for taxes, fitting and transport, Rs 0.37 lakh for panel and cabling: Rs 3.65 lakh.
- Payback 3.4 years at 2011 prices; about 10 days to change over.
- Most mills run 4 to 20 expellers, so this is usually a phased replacement.
Prove it on your own expeller
The saving is the difference in rated horsepower, which assumes both motors work equally hard. Put a sub-meter on one old expeller for a week and record kWh per quintal of cake pressed, then do the same after the swap. If oil recovery also improves, as the report expects from the gearing, record oil out per quintal too: that is money the kWh figure misses.
One expeller and a ten expeller mill
- One: 22,200 kWh x 0.675 = 15.0 t CO2 a year
- Ten: 222,000 kWh, 150 t CO2, Rs 10.7 lakh at the report's tariff
- The report says 20.0 t for one, using an older grid factor
Grid at CEA's FY 2025-26 factor, an estimate.
What Senseible does here
Senseible reads your electricity bills into monthly records linked to each bill, with CO2 for the units, so a phased expeller change shows up month by month. Planning to borrow for the expellers? The green loan check lists what a lender asks for.
- Green loan readiness check
- Alwar mustard oil mills: kWh per quintal
- Flat belt or V-belt on an expeller
- Edible oil carbon footprint per litre
Sources: BEE, Detailed project report: energy efficient expeller in oil mills, Alwar oil mill cluster (2011, SAMEEEKSHA), CEA CO2 Baseline Database, version 22.0
Last reviewed 2026-11-01. Report figures are from a BEE SME programme project report; costs and paybacks are at the report year's prices. Check today's tariff and a current quote.