Voice of the industry: as with all manufacturing, foundries struggle to keep electric costs low. How has your plant reduced its cost of electricity? (Shakeout).

The low cost of electricity here in the Northwest makes private alternative generation a losing proposition. At Columbia Steel, we concentrate on efficiency improvements to keep electricity costs. down. Our local utility will furnish consultants to perform energy audits and make recommendations. They then provide substantial rebates for whatever improvements we implement. The state government also gives a 35% tax credit on the cost of energy projects.

For example, we installed a demand control system for our big arc furnaces. Furnaces are by far the biggest source of demand spikes and the only devices we can shut down intermittently without much harm.

With the utility's help, we also performed a complete lighting audit, evaluating every light bulb on the premises. We compared existing types, wattages and hours of use with the best current alternatives and developed a spreadsheet to show paybacks for upgrading each. With this as our guide, we replaced about 1000 fixtures, resulting in better quality light and lower energy use.

We just replaced two of our main air compressors (150 hp each) with more energy efficient equipment. One has a variable speed drive, the optimum way to accommodate variations in demand. Next we plan to add more air storage tanks and an intelligent control system that will manage all the compressors, turning them on or off in response to demand.

We examined our baghouses, replacing several fan impellers with more efficient designs, and then changing sheaves and belts to optimize fan speed, horsepower and airflow. More savings stemmed from automatic timers that interlock dust collectors with the equipment they serve and turn them off when not needed.

--Bruce Schacht, plant engineer, Columbia Steel Casting Co.

D&L Foundry is located in Washington, an area that touts the most inexpensive electricity in the nation. As a result, we did not suffer any rate increases during last year's energy 'crisis.' (Our public utility district owns and operates two hydroelectric dams on the Columbia River.)

However, while the power is inexpensive on a per kilowatt basis it is the primary energy source for our operation. We also pay significant charges for demand and power usage that is below a 0.95% power factor.

With this in mind, we have started to concentrate our efforts on optimizing our power usage by scheduling our melt demand on a more consistent basis throughout the day. We try not to create production situations that require surges of energy that up our usage and increase cost. We also have added power factor correction equipment to help monitor and maintain our power factor within the set tolerances.

--Jason McGowan, operations manager, D&L Foundry

Foundries can reduce their energy budget by improving the efficiency of plant energy use. The first step in this procedure is an energy audit. Do an inventory of plant equipment, production, environmental, lighting and office energy use. An audit allows you to identify potential energy conservation measures (ECM). After determining an ECM, such as upgrading a compressed air system to eliminate leaks, perform a feasibility study to solidify details, and identify actual costs and benefits. The strength of the feasibility study will provide justification for performing the upgrade.

An example of this technique in action is a foundry that performed an energy audit and realized that a cupola air scrubber was responsible for 51% of the electricity budget. In this case, the suggested upgrade wasn't complex--the foundry controlled scrubber operation during the on-peak hours of the day by increasing use during off-peak hours, which reduced the billing demand to 500 kw and the annual bill by 12% The improvement of the plant's bottom line was accomplished through a clearer understanding of the impact of electric rates on the cost of plant operations.,.and without a rate reduction.

--Robert Sugra, retired, PP&L EnergyPlus Co.

We've reduced electric costs at Varicast primarily through controlling usage. We have switched to off-peak melting at both plant locations to take advantage of the reduced rates it offers. When business is slow, this method works, but if you can't melt solely in the off-peak hours, you must pay the higher rates. This has reduced electric bills at each of our two plants by $5000/ month. However, some of these savings are offset by the higher labor rates for people working off-shift.

We've also looked into contracting with the electric company for a demand rate as opposed to a premium rate. This involves keeping peak demand below a certain point for the entire month in exchange for a lower rate.

--Tony Bella, director of technical services, Varicast, Inc.