February, 1999

Superior Controls engineers are successfully integrating a major automation project to control and monitor equipment associated with two, 5-megawatt, gas-fired turbine generators.

With the advent of energy deregulation throughout New England, many heavily energy-dependant manufacturers and communities have been installing their own gas-fired turbines to produce both electricity and steam. These turbines can produce electricity at rates as low as .04 cents per kilowatt-hour or about 60% the going rate for industrial customers.

One Superior Controls customer, a major New England based manufacturer, will rely on the two turbines to generate 80-to-100% of their electric needs, as well as to produce 50,000 lbs. of process steam. Each turbine uses high pressure natural gas to continuously run at 15,000 RPMs. Each turbine is attached to a generator nominally rated at 4000 KW. The 900-degree F exhaust is directed into a Heat Recovery Steam Generator (HRSG) to produce a steady supply of 135 PSI steam. Parallel equipment is used to ensure that the customer can utilize both the turbine-generated power while continuing to draw a nominal load from the local utility.

An existing Bailey Distributed Control System (DCS), previously installed for the fossil fuel boilers, was expanded to control the feedwater loop and the exhaust diverter valve.

Allen-Bradley programmable logic controllers (PLCs) monitor and control the equipment associated with the two turbines and the Balance of Plant (BOP). The BOP PLC monitors and controls the HRSG, ventilation, fire detection systems, and the electrical load shedding system. This entire project- which is on a fast track- will be implemented in approximately four months.