Energy Saving Measures Implemented in Auxiliary Motors in a Medium Scale Foundry - A Case Study

Abstract

Energy Efficiency Improvement in Auxiliary Motors in a medium scale foundry industry resulted energy savings in sand plant cooler and shot blast machine as below:
1. Sand Plant Cooler Motor
Existing Motor: 20 HP, Energy consumption = 11.6 kWh (hourly basis)
New Energy-Efficient Motor: 20 HP, Energy consumption = 10.0 kWh (hourly basis)
Daily Energy Savings for 20 hrs / day: 11.6 − 10.0 = 1.6 kWh x 20 = 32 kWh/day
Energy Savings Percentage: ≈ 14% through design modification and improved motor efficiency.
2. Shot Blast Machine – Impeller Motor
Existing Motor: 20 HP, Energy Consumption = 8.7 kWh
New Energy-Efficient Motor: 20 HP, Energy Consumption = 7.7 kWh.
Daily Energy Savings for 12 hr/ day : 8.7 − 7.7 = 1.0 kWh x 12 = 12 kWh/day
Energy Savings Percentage: ≈ 11.5% through design modification and improved motor efficiency.
The combined replacement of these two motors results in 44 kWh/day savings. Over 300 operating days per year, this translates to 13,200 kWh/year, reducing both operating costs and carbon footprint. CO2 reduction achieved per annum is 9.372 ton and its oil equivalent is 1.135 mtoe.