Over a four week period earlier this year, our Energy Efficiency Team worked with the plant operations and maintenance departments at our South Bend plant to fine tune our compressed air system. After collecting data, making adjustments, and analyzing results, we saw a 65% reduction in kWhs/production unit and a 68% reduction in compressor run time.
South Bend has a rotary screw compressor that originally maintained a 115-125psi pressure range with a load/idle operating mode. Over the duration of our tests, we changed the pressure range to 95-120psi and switched to a Load/Idle/Stop operating mode. The operating mode change allows the compressor to shut the motor off instead of idling between cycles when the plant is slow. Once the plant gets busier and the cycle times start to decrease, the compressor automatically switches back to idling.
Our maintenance team also went through the plant to identify and repair any air leaks they found. We used power meters to compare the air compressor’s energy usage and run times before and after the changes. With the success of this test in such a relatively short time, we’re currently using a similar process to assess compressor energy usage at other plants.
“These tests help make sure we are using the correct amount of energy and properly sized equipment for our operations,” said Nathan Onchuck, Energy Sustainability Engineer. “We operate many different sites across multiple states. Improving the energy efficiency of our production facilities allows us to more reliably service our customers and reduce the environmental impacts of our operations on our communities.”