Steel Plant Controls Power Demand

Steel-bar producer Republic Technologies International recovered the installed cost of a demand management system in a Canton, Ohio, facility in under 6 months and projects ongoing cost savings up to $70,000 monthly.Electric power costs of $2.7 million per month are a significant share of operating expenses.

By Staff March 1, 2001

Steel-bar producer Republic Technologies International recovered the installed cost of a demand management system in a Canton, Ohio, facility in under 6 months and projects ongoing cost savings up to $70,000 monthly.

Electric power costs of $2.7 million per month are a significant share of operating expenses. The contract with its electric power provider includes a demand limit, above which the price of power significantly rises. A curtailment clause gives the utility the option to mandate immediate reduction of load to base levels.

The solution was to inhibit or shed electric furnace loads to control power demand. The specified system totals electric meter pulses and projects demand within the 30-minute fixed-demand interval. Furnace operators select priorities to determine the system’s actions based on the demand forecast.

The new system utilizes a redundant pair of processors with backup communications modules tied into the existing control Ethernet. Remote I/O panels at the three furnaces use a redundant fiber-optic loop to communicate with the processors. In addition, a new power monitoring system on the plant mains provides additional power-quality data.

For more information on power monitoring and control systems from Rockwell Automation, circle 453 on the Reader Service Card.

From Pure Power, Spring 2001