The Challenge
A metal casting foundry with three production sections — melting, moulding, and fettling — had attempted energy reduction initiatives three times in five years. Each produced modest results in isolation. Total energy consumption per tonne had declined only 4% over the period despite meaningful investment. The plant manager theorised that gains in one area were being offset by invisible losses in others — but without cross-plant visibility, the theory couldn't be tested.
The fettling section had twelve air-powered grinders that collectively consumed 28% of all compressed air. Seven of the twelve were running continuously during their shift regardless of whether they were actively in use. The moulding section had one compressor permanently loaded to supply a sand-conditioning circuit requiring only 15% of that compressor's capacity. The melting section had good energy discipline but was subsidising the other two sections' waste in the shared utility infrastructure.
What Changed
Section-level and machine-level air and electricity monitoring across all three production areas. A consumption heatmap by section, machine, and shift.
The heatmap made cross-section comparison immediate. Section management could see that fettling consumed 3.2× more utility per tonne than moulding. The intervention in fettling — auto-shutoff valves on grinder air supply during idle periods — was straightforward once consumption was attributed to specific machines. Compressor loading was optimised from six units to four simultaneously, based on actual demand profiles.
Results
within 8 weeks
5-year 4% trend reversed
across all three sections
“When energy initiatives produce modest results despite genuine effort, the problem is usually attribution, not ambition. Without the ability to see which section, which machine, and which time period is responsible for waste, improvements in one area are invisible against the noise of losses elsewhere. Visibility that connects cause to cost turns scattered efforts into targeted ones.”