Emerson’s optimization technology helps Young Unit 1 improve ramp rate by 70 percent

June 3, 2008

Pittsburgh, June 3,  — At Minnkota’s Milton R. Young station, use of Emerson Process Management’s SmartProcess Unit Response Optimization (URO) technology is translating into dramatic operational gains, including a 70 percent improvement in ramp rate. These performance improvements are helping the station generate megawatts more efficiently as part of the Midwest ISO in which it now participates.

The Young station is owned and operated by Minnkota Power Cooperative, which provides electricity to 11 associated distribution cooperatives in eastern North Dakota and northwestern Minnesota. Young Unit 1, located near Center, N.D., is the primary source of electric energy for approximately 110,000 customers. This lignite-fired, 250-MW unit, which began operation in 1970, is equipped with a Babcock & Wilcox (B&W) cyclone boiler and General Electric steam turbine generator.

For years, Young Unit 1 operated as a base-load unit in which megawatt production levels remained relatively constant. This changed when Minnkota recently started participating in the Midwest ISO, an operating environment in which revenue is dependent on a station’s ability to respond quickly and efficiently to constantly changing load demand. This environment was particularly challenging for Young Unit 1, which was now also required to offset megawatts whenever recently added wind farms are unable to meet demand.
Previously, Unit 1’s response to load setpoint changes often resulted in over/undershoot and lagging load response, both of which contributed to lost revenue. To help resolve this issue, in the fall of 2007 Minnkota implemented Emerson’s SmartProcess URO technology to meet fluctuating demand more efficiently. The SmartProcess URO solution, which uses actual plant operating data to create a model of process response and unit characteristics, has been running continuously ever since.

The results have been dramatic – a 70 percent improvement in ramp rate, from 2 MW/min. to 7 MW/min.; a 2-megawatt reduction in over/undershoot; and a 4-PSI average decrease in throttle pressure, contributing to overall machinery health. As an additional benefit, the SmartProcess solution has also been instrumental in helping Young Unit 1 pass its routine turbine steam inlet valve tests.

“Because the Young Station is now participating in the Midwest ISO, we need to ramp to setpoint more quickly, with reduced variability in megawatts and pressure,” explained Dana Stumpf, technical supervisor, Minnkota Power Cooperative, who adds that the SmartProcess URO solution will be installed this year at Young Unit 2. “Emerson’s SmartProcess Unit Response Optimization technology has significantly improved unit response, which is critical to our capability to operate more profitably.”

The SmartProcess URO is part of Emerson’s comprehensive suite of optimization technologies seamlessly embedded within the Ovation expert control system. Incorporating fuzzy logic, advanced analytics and model predictive control, these technologies offer adaptive improvement solutions which help utilities achieve optimized equipment performance for emissions compliance, temperature control, efficiency and overall continuous operational improvement.

Using nonlinear dynamic feedforward and model prediction, the SmartProcess URO builds upon Ovation’s existing unit coordinated control capability to further enhance the boiler and turbine response for tighter overall control and more efficient operation. Use of SmartProcess URO technology translates into additional revenue opportunities for power generators by enabling units to more accurately hit targeted setpoints with minimal megawatt overshoot, thereby contributing to reduced fuel costs; helping units quickly ramp to targeted setpoints and allowing them to generate revenue as quickly as possible; and enabling units to follow load demand, making it possible for them to compete in the ancillary power services market.

“Emerson understands that the power generation industry’s operational and financial climate has never been more demanding,” said Bob Yeager, president of the Power & Water Solutions division of Emerson. “Because of its ability to dynamically optimize plant operations during constantly changing demand, our SmartProcess optimization technologies can help power producers improve plant economics and achieve a timely return on their optimization investment.”