Conserving energy to reduce costs.

In an era of increased competition, every penny counts in cost reduction. One area that foundries are focusing on, as evidenced by three of the eight presentations of the Marketing/Management Div., is energy conservation.

In his paper on deregulation in the electric industry (095), R. Sugra, PP&L EnergyPlus Co., L.L.C., used the experiences of a foundry to give a better understanding of how the price of an electric commodity can be reduced, and how additional reductions in bottom-line energy costs can be achieved through the more efficient use of electricity throughout a plant.

According to Sugra, the first step in reducing costs is to find out where and how energy is being used through the performance of an energy-efficiency audit. Next, a feasibility study is performed, which is more detailed and identifies the costs and benefits of implementing an upgrade. If the plant operator chooses to move forward on the strength of the feasibility study, design and engineering follows. Finally, the construction phase occurs in which the focus between the foundry and utility is on transmission and distribution, energy management, metering, and financing for such projects.

With an audit, the subject foundry discovered that a scrubber on its cupola was using 58% of the total plant electric requirement and was responsible for 51% of the electrical budget, or $164,736/yr. Through the control of the scrubber operation during peak hours of the day, the billing demand was reduced to 500 kW, and the annual bill was reduced by more than 12%.

In their paper on energy conservation in foundries (032), India's R. Singh, HMT, Ltd., and V. Singh, BM Enterprises, discussed how foundrymen increase their profitability by modifying their existing production facilities and adopting energy-efficient technologies that will have greater impact on reduced energy consumption and optimization.

With energy costs making up 10-15% of a foundry's operating cost, evaluation of energy performance is a logical starting point of any conservation program, according to the authors. It is important to know the actual amount of energy consumed in a particular activity, and the installation of an energy monitoring system is the most important tool in achieving this goal. This measuring tool can detail how and what quantity of energy is used in mass-consuming areas such as melting, compressor house, ovens and ladle heating, auxiliary equipment, and molding and coremaking.

The melting, holding and processing of metal consumes 50-75% of a foundry's total energy consumption. The consumption could be minimized by 58% through effective and judicious management of melting practice.

The high cost of operating an air compressor can be reduced by running it at a pressure no higher than what is required, avoiding leakage from the air line, cleaning the suction air filter frequently and installing oversized motors.

The authors suggested replacing traditional electric- and oil-heating ovens with ovens using infrared lamps and a thermax heating system. Also, energy saving devices tested on mercury, sodium and fluorescent lamps have shown 20-30% cuts in the monthly energy bill.

In his paper on preparing a foundry for electric industry restructuring (117), E.M. Cooley, TU Electric/Lone Star Gas, provided foundries a foundation upon which to build energy-purchasing strategies for the future.

These strategies, which also prepare foundries for taking advantage of the new electricity markets, include:

* know the basics of electricity generation and delivery - Since electricity consumption changes with the time of day and the seasons, the generation assets must be large enough to supply consumption peaks that may last only 6-8 hrs for a few days each year. This is the reason electricity prices are higher at some times of the day for a few days each year. Delivery to a facility normally accounts for 30-50% of the total cost of electricity;

* understand the potential electrical market in your geographic area - Characteristics that affect the pricing of electricity include season weather patterns, the size of the electric generating capacity reserve margin, historical prices and the attitude of the regulatory bodies;

* document and understand the way you use electricity-Energy consumption is driven by production needs and your ability to move production to off-peak periods. Controlling demand peaks also can impact your electricity cost;

* identify non-price issues you want your provider to address - Decide if you want to pay for such services as energy audits, assistance with technology applications, power quality analysis and assistance, advice on how to purchase less expensive energy, special billing services and cash incentives for efficiency improvements;

* know your tolerance for risk - In restructured, open-access electricity markets, the price volatility risk can rest in several places and because of the just-in-time delivery nature of electricity, may be much greater.

Also featured were presentations on the AFS CD-ROM project and metalcasting engineering systems.