Layered Automation Helps Chart College's Course
As can be expected, WMU is always building onto and upgrading its facilities in order to retain its status as one of the nation's top 100 public universities. The most recent project undertaken at WMU involves the new construction of the Energy Resource Center (ERC), which will serve two new WMU facilities.
The ERC will provide steam and chilled water to the new 330,000-sq-ft College of Engineering and the 50,000-sq-ft Paper Pilot Plant. Both facilities are part of WMU's new Parkview Campus, a 20-acre site that is located about four miles away from the main campus. The Paper Pilot Plant opened in October 2002, while the main College of Engineering building is scheduled to open in September 2003.
WMU relied on Armstrong Service Inc. (ASI) to accomplish the turnkey project and to act as the single source for all phases of the project, including engineering, procurement, project management, commissioning, training, and follow-up engineering.
Built to ServeOriginally, WMU planned on the development being an own-and-operate project. ASI was part of a competitive analysis to choose a company that would build and operate a steam, electric, and cooling plant under a 30-year contract with WMU. ASI won the analysis and was chosen to build and operate the plant, with construction beginning in 2000. Later in construction, due to financial reasons, WMU chose a more traditional model of operation while retaining ASI to design and build the boiler/chiller plant, which is called the ERC.
"We were looking to get out of the energy-producing business," said Ray Kezenius, senior project engineer at WMU. "We were hoping to have ASI do a turnkey operation where they would be the utility and do the construction, and we would just buy energy and chilled water from them. In midstream we had to change our approach, but we worked it out so ASI would act as a general contractor to design and build the ERC, but we would pay for it."
ASI's project developer for WMU was Bruce Billedeaux. As project developer, Billedeaux provided preliminary engineering and financial forecasting for optimization projects, while working as a team member with the business developer to provide solutions for WMU. "It just so happens that on the WMU project, I was also the project manager, which meant I was responsible for construction and commissioning of the project," said Billedeaux. Basically he oversaw every aspect of the project.
The end result is the ERC, which is an unstaffed 10,000-sq-ft free-standing building that houses both the chiller and boiler plants. The boiler plant consists of two 400-hp watertube boilers and one 350-hp firetube boiler rated for 150-psi steam. The boilers are capable of burning multiple fuels to provide redundancy and economic stability, and the condensate system uses gravity return and steam-powered pumps.
"ASI came up with some unique ideas on fuel flexibility. We've got natural gas, as well as No. 4 fuel oil backup, so we have flexibility to switch to different fuels, if need be," said Kezenius. "The boilers have been up and running, and so far things are going well. We have been providing steam to the College of Engineering construction site, where we have some of our air handlers that are being used to provide temporary heat."
At press time, work was just being completed on the chiller plant. The ERC has three 700-ton chillers with primary and secondary pumping systems. Two of the chillers are variable speed and one is a high-efficiency constant speed. The chilled water system is entirely variable speed and dynamically adjusted for energy savings.
During construction, it was determined that the College of Engineering would not be able to use the free cooling configuration that was in the initial design; therefore, a condenser water storage sump was added to the ERC to allow for winter operation of the chilled water system.
ASI took growth into account when designing the ERC, and space has been provided for an additional chiller if needed in the future. A yard adjacent to the ERC has also been enclosed so there's room to evolve into a bigger facility in the future. "We also ran additional chilled water lines in anticipation of future expansion of the College of Engineering. The main line is in place, so it will just be a matter of tying in to the ERC. We tried to plan for future growth and cover all our bases," said Kezenius.
A Substation is BornIn addition to the ERC, ASI was also responsible for constructing a 10-MW substation and 15-kV underground electrical distribution system, which, along with the ERC, will serve the new College of Engineering and Paper Pilot Plant. The Paper Pilot Plant, which opened last fall, houses a modern, high-speed paper coater acquired from Boise Cascade Corp's Portland, OR facility. The coater will be the only such equipment in North America that is not affiliated with a private company.
As Billedeaux noted, "We don't normally build substations." But WMU was an exception. What happened is that early on in the project, WMU wanted ASI to build a cogeneration plant. The university already had a cogeneration plant on its main campus, and the thought was to have another one on the smaller Parkview Campus.
"The problem is that in West Michigan, all the nighttime power is coal and nuclear, so the energy cost is about 2.5 cents/kW," said Billedeaux. "The problem is the smaller cogeneration plant would've needed natural gas reciprocating generators, which are expensive to maintain and operate. When we did our analysis, we said they should put another turbine in the central power plant, and they could wheel power during the peak daytime periods from the central plant nearly free of distribution charges if they built a 120-kV transmission-level substation. It's an 8-year simple payback on a substation that's going to be there for more than 30 years."
ASI did not design the substation; rather, it acted as the construction manager and hired specialist Glenn Keates of Cummins and Barnardto to design and build the substation. "We just told them how big it had to be," said Billedeaux.
A Layered ApproachAs mentioned earlier, the ERC is unstaffed. "The intent all along was to have the ERC be a remotely operated and monitored facility," said Kezenius. "There's a big money savings when you don't have to send a boiler operator to be stationed out there. The ERC will run independently and our people will check in on it periodically."
In order to be remotely operated and monitored, ASI installed the Armstrong "Energy Optimization System" (EOS), which is comprised of the Armstrong optimization software running on the Tridium "Niagara" framework.
"EOS acts as a supervision layer over distributed controls in the plant. We are using systems such as Honeywell flame management controls and Trane 'Tracer.' These are interfaced to the EOS through several standard protocols, such as LonWorks, ModBus, and BACnet. Each distributed system is responsible for complete control of the associated equipment, while data and remote commanding is the task of the EOS," said Billedeaux.
The EOS is designed in this layered concept to allow for safe operation of plants that are operated via the Internet. By design, safety interlocks and critical operations are either hardwired or are located in devices that are not accessible over the network. While nearly all information is available over the network for trending and analysis, the ability to command specific equipment is limited to those items that are necessary to operate the plant.
Another reason for this layered approach is to be able to use the controls systems ("canned programs") provided by the manufacturers who created the equipment. For example, Billedeaux said that the Honeywell flame management system is wonderful because it's a defined-purpose device. "It doesn't require any programming. It works out of the box. You set up the flame curves inside of it at start-up, and then you have a machine that runs day in and day out, and you don't have to worry about anyone messing with it. If the whole automation system goes down, these boilers can still be firing."
The same is true for the other subsystems installed in the ERC. Billedeaux used the manufacturers' canned programs and then hooked them altogether. He says this is a safer approach, because there are multiple levels of controls that are made for specific purposes, hence, it's much harder to remotely disable the plant.
"If you have a single level of control, like a building automation system by one manufacturer, how would you keep people from accessing certain types of life safeties?" asks Billedeaux. "The only way to do that is to go in there and put in time delay relays, but then you're making a very complex wiring system. Instead, use defined-purpose electronic controls and then communicate with them. By their nature of design, they hide safety points you can't get to."
The EOS, being Web based, allows for a combination of in-house and outsourced monitoring of the ERC. The WMU central plant boiler staff will use the system via a standard browser to operate the plant on a daily basis. ASI will remotely collect and analyze data from its main office in Orlando via the Internet. Several WMU finance personnel will access the plant via the campus WAN and standard browsers to view fuel consumption and forecast data.
The EOS is comprised of three Tridium "JACE" panels and one Pentium class touch screen PC. The PC is a NEMA 4 panel that acts as the primary interface while in the ERC. Except for a few points that are interfaced directly at to the JACE panels, all information is extracted from the distributed control via the data bus.
What Happens NowWhen construction is finished at the ERC, ASI will still stay on in order to optimize the system - basically to perform long-term commissioning. Billedeaux will be at the plant one day a week for the next year in order to make sure everything is set up properly. After that, the company will continue to monitor the system remotely. ASI feels strongly about this type of setup and builds it into the up-front cost of the project.
"Most of the time, what happens is the engineer finishes up a project and leaves and then gets called back when things don't work. The enduser typically doesn't have a budget to have an engineer stick around, then the place never works like it's supposed to. These are fairly complex systems, so we'd rather have somebody around to meet with the staff weekly to clear up issues."
Indeed, one of the biggest issues for Kezenius is simply working with all the different entities involved with the project. "We have design professionals that we hired for the College of Engineering and the Pilot Plant. We have a design specialist from the paper industry. Then ASI has its own design professionals that work on the ECR. All of them use common lines for chilled water and piping, so there is a tremendous amount of interface because of the commonality of these feeds," he said.
Kezenius added that it's a daunting challenge to have three or four firms get together and coordinate who is doing what and to delineate each firm's areas of responsibility. "We're the traffic cops in the middle who keep track of all this," he noted.
But with the project nearing its end, both Billedeaux and Kezenius are happy with the outcome. As Kezenius stated, "When the infrastructure is complete, we'll have a state-of-the-art facility with a Web-based control system that will enable us to operate and control the systems remotely. That's where the future may be heading."ES