New applications: Digital control grows in power plant construction

By Control Engineering Staff December 6, 2006

Providers of digital control systems and fieldbus networks like to discuss the savings these systems can offer over older hard-wired analog approaches, but to realize the full impact, effective networks have to be designed into the plant from the outset. The electric utility industry, long a conservative bastion of analog technology, is putting the benefits of digital networking and control to work in its current construction activity. The latest announcement is from Plum Point Power Partners for their new pulverized coal-fired plant in northeastern Arkansas. They have selected Emerson Process Management ‘s Plant Web architecture with Ovation expert control system as the backbone of the new operation.

The new 665 MW plant will use an IHI subcritical boiler and Toshiba turbine, all controlled by Ovation using 138 FOUNDATION Fieldbus segments and 58 Profibus -DP segments to network all the intelligent field instrumentation. While this technology is not new, its application in power plants has just started in the last year with a rebound in new plant construction. ( Click here to read an earlier article.) Plant designers, including Black & Veatch in this case, now understand the savings available over older technologies and are putting them into practice.

“Emerson’s PlantWeb digital plant architecture has been proven across a number of industries to lower installation costs, ensure a fast startup, and improve ongoing plant operations and maintenance,” says Bob Yeager, president of the power and water solutions division at Emerson. “There is growing recognition among power producers that these technologies translate into tangible economic and operational advantages.”

Emerson’s order books bear this out in that Plum Point is only one of seven new power plant projects they report having received during 2006, and the year is still not over. These projects total 5,505 MW of new generating capacity and will all begin commercial operation within the next five years. These add to Emerson’s existing installed base controlling more than 35% of all electricity generated in the U.S., according to the company’s estimates.

— Control Engineering Daily Daily News Desk Peter Welander , process industries editor