Comment

April 2009

Fossil fuel group boosts power automation

At Bechtel, an architectural engineering firm in Frederick, Md., Henrik Johansen is assistant chief engineer of instrumentation and control who designs power plants and buys power systems. As a member of the ISA77 fossil fuel power standards committee, he realizes power automation needs more standardized documents to help these kinds of companies.

Many plants have older and experienced operators retiring. The concept of having an automation start-up and automatic shutdown system to assist younger inexperienced operators in the plant operation with on-line feedback is important. Given the sequence falls under best operating practices the belief is repeatable start-ups will result in less energy use during startup.

That is why the ISA77 committee is forming a new subcommittee, ISA77.22, on power plant automation to help those in the industry with standardized terminology and methodology and standardized concepts. “We can’t give specific guidance in how to control a power plant; every plant is unique, and we can’t cover every permutation,” Johansen said. “But we still have to be engineering things unique to each individual application. If we can work in the vein of the other ISA77 series standards, we can publish something helpful and in a consistent framework.”

“End users see the importance of power plant automation as a means to address aging workforce and energy efficiency issues,” said Dan Lee, senior application consultant at ABB in Wickliffe, Ohio, and co-chair of ISA77.  The main purpose of this technical report is to “provide advice and guidance for the development of fossil power plant automation,” Lee said. “The start-up and shutdown sequence is process dependent.”

Where plant automation systems have been implemented with past technology, Lee said, “renewed interested seems to be based on a group of industry peers who have seen successful and unsuccessful practices and are interested in taking the lessons learned to see if they can improve the application.” However, the committee is not planning on developing a standard but rather a technical report or recommended practice, he said.

The goal of the document is to clearly define the terms, architectures, engineering design, and documentation of plant automation systems, Lee said. The committee expects to provide process specific sequences as examples. The document will help end users and suppliers to better understand the scope and purpose of a plant automation system.

Startup, shutdown applications

While the other ISA77 standards talk about various aspects of controlling a power plant, the new document will relate to automating the startup and shutdown of a power plant—just one more aspect in the overarching automation of starting and stopping of sequences, Johansen said.

“Generally speaking, the higher level automation you want to do, the easier it gets as you get a framework to build it on,” he said. “Europe and Japan have done this before. By building a framework to automate the start and stop, operators will be free to do other things, such as having more repeatable control for a plant. There will not be individual operator idiosyncrasies; it’ll be a standardized way of bringing a plant up and down.”

The committee’s initial effort is to define basic principles and the level of automation; the members intend to address three processes: combined cycle, Rankine cycle (drum boiler), and supercritical once-through boilers, Lee said.

Since meeting for the first time at ISA EXPO in Houston last year, the committee has set an aggressive deadline. At the second meeting in February, the committee prepared some rough drafts of thought processes that “may or may not be part of the standard we’ll post on the web site for the committee,” Johansen said.

“Further down the road, we might divide the standard in pieces and have different people write those. It’s always easier to critique and edit when you have a starting point.”

So far, the ISA77.22.01 committee has prepared the document’s outline, including its scope and purpose. The next meeting is 11 May at the ISA POWID Symposium in Chicago. Lee said a first draft could be ready around fourth quarter 2009, but the committee has preliminarily set fourth quarter 2011 as the published date for this document.

Ellen Fussell Policastro (efussellpolicastro@isa.org) writes and edits Standards.