grand coulee dam
Sweeping savings and quick ROI

Seize the Savings

A fresh approach yields sweeping savings for a quick ROI

Hydroelectric power plant benefits from having an ongoing compressed air energy audit.


At a plant manufacturing turbines for hydro-electric power plants, excess capacity had been a source of comfort for many years despite recommendations for system updates. Four modulating, twenty-year old compressors, two 75 hp, two 25 hp, supplied the system—without central controls—causing excessively high energy costs. When a new plant engineer came on board, he took a closer look at the energy efficiency. Having attended a Kaeser Compressed Air Seminar, he knew a systems approach could unlock significant savings.


Kaeser ran a KESS (Kaeser Energy Saving Simulation) using supply side audit data and designed a complete system solution that would dramatically reduce the specific power from 62.0 kW/100 cfm to 17.5 kW/100 cfm. New energy efficient compressors, an air receiver, as well as a system master controller were installed. The new system has the same number of compressors and total horsepower as before, but it provides even more flow.


The Sigma Air Manager (SAM) master controller monitors the four new compressors and selects the most efficient combination of units to meet the plant demand. With its built-in SAC Plus software, SAM continually tracks energy consumption so the plant benefits from having an ongoing compressed air energy audit. As a matter of fact, the specific power has been reduced more than anticipated—all the way down to 16.7 kW/100 cfm.

  • Annual Energy Costs of Previous System: $59,780 per year
  • Reduction in Specific Power: 45.3 kW/100 cfm
  • Annual Energy Cost Savings: $22,680 per year
  • Additional Savings in Maintenance Costs: $7,240 per year 
  • Total Annual Savings: $29,920
  • Simple Payback Period: 14 months