Then we’ll try out a pilot project just to make sure it isn’t just ‘salesman talk.’ We just tried out new lamps in our lighting fixtures in the plant. If it works in the entire plant like it did in the pilot, we stand to save almost $33,000 a year.”

The plant recycles all possible manufacturing waste. This not only reduces landfill costs, but sometimes adds a little income. Items recycled in one way or another include wood pallets, cardboard, computer equipment and metal chips from the machining processes. Hinze and Chandler also turned a critical eye to manufacturing processes. In one operation, by changing from grinding to hard turning, they cut the cycle time in half, reducing electricity consumption and increasing productivity. Going from electric heat to natural gas reduced cost on the carburization process. When the price of natural gas went up, they purchased regeneration U-tubes to cycle waste heat back into the system to reduce consumption. Automating the cooling system with variable frequency drives allowed them to shut off pumps when there was no demand.

Chandler concludes, “We’re constantly looking for ways to reduce energy costs. Our owner is concerned with environmental protection and recycling, so it’s just a company mindset. Sometimes it’s hard to do a project, but we do it when it makes sense.”

The many reasons for increasing energy efficiency and thereby reducing consumption include numerous environmental and social goals, but reducing expenses still ranks as number one when businesses and other entities look at the situation. Another example of reducing electrical energy consumption lies outside the walls of a manufacturing plant—it’s the invisible workings of a municipal swimming pool. Municipalities are large energy users from water and wastewater treatment to facilities. The pumps that keep water for swimming fresh and clean are another source of energy use—and expense.

Swimming in costs

Tim Friend, plant supervisor of the South Windsor, Conn., community swimming pool complex was keenly aware of the operating expense of running a 10 horsepower, a 20 horsepower and two 30 horsepower pumps used in cleaning the million-plus gallons of water contained in the facility’s three pools. The water must be constantly pumped through a series of filters 24 hours per day, every day in season. The pumps previously operated at full horsepower constantly.

“We wanted to lower our high power bills,” says Friend. “We knew we were wasting energy via running the pumps at full power—especially after hours. Fewer impurities are in the water when nobody is swimming, so by slowing the flow at night, we knew we could still maintain adequate filtration in the pool and the same levels of water quality.”

So, Friend consulted with Brian Robinson, a sales engineer with FlowTech Inc., a South Windsor, distributor of ABB products who had assisted on previous projects in the water treatment plant. They evaluated the impact that implementation of ABB variable frequency drives would have on the problem.

After installation, the pump speeds were set back using the on-board time clocks that initivisitate pre-programmed, pre-set speeds in the VFDs. Pumps were programmed to run at 90 percent power during open-pool hours, and to ramp down to 60 percent for 12 hours each night after pool close. These settings were anticipated to yield an energy consumption reduction of more than 65,000 kilowatt-hours (kWh) per season—and save the pool more than $7,000 in operational cost annually.

To view the accompanying sidebar article to this story, "How to Get Management Approval", go to www.automationworld.com/view-4000.