Redesigned Cooling System Wins National Honor

Redesigned Cooling System Wins National Honor

By Jeff HarrisonUniversity Communications
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The UA's newest chilled water plant replaced an aging facility that was on the verge of collapse. (Photo by Jeff Harrison)
The UA's newest chilled water plant replaced an aging facility that was on the verge of collapse. (Photo by Jeff Harrison)
One cost-saving measure is making ice overnight when generating costs are lower, storing it in the containers shown here, and then using the melted water for the chilled water system. (Photo by Jeff Harrison)
One cost-saving measure is making ice overnight when generating costs are lower, storing it in the containers shown here, and then using the melted water for the chilled water system. (Photo by Jeff Harrison)
South face of chilled water plant. (Photo by Jeff Harrison)
South face of chilled water plant. (Photo by Jeff Harrison)
Gordon Bush
Gordon Bush

Facilities Management at the University of Arizona has been recognized nationally for something that is rarely seen or thought about on campus but is universally appreciated, especially here in the desert Southwest.

Building Operating Management, a trade publication for facility departments around the country, has given its FMXcellence award to the UA and nine other departments around the country for "adding value to their organizations." The UA was honored specifically for the "monumental renovation" of the campus chilled water system.

This is the first year of the magazine's program. Some of the other winners include the Smithsonian Institution, Nike Inc., the University of Illinois and the Gilbert Public School District in Arizona.

The UA essentially rebuilt the aging and inefficient system that provides air conditioning for a campus where summertime temperatures can last six months out of the year. The system has been steadily undergoing repairs and technological advances for more than a decade to stem both frequent breakdowns and rising utility costs.

The UA's award-winning chilled water production and distribution system spends the evening and early morning hours freezing water that is then used to cool buildings across the main campus and at the Arizona Health Sciences Center. The process moves the bulk of the UA’s electrical load from the hot daytime hours to the cooler nighttime hours.

Last summer, air conditioning company Trane awarded the UA its Energy Efficiency Leader in Education Award – the first time the award had gone to an educational institution – for being one of a few institutions to have such a project up and running.

Most people know little, if anything, about the chilled water system at the UA, but can certainly appreciate it when they step inside a campus building during a sweltering summer afternoon. Over the years, the UA built three chiller plants that worked independently of each other but delivered water via a single loop. As new buildings were added, the system began to strain under the growing demand, especially for the buildings farthest from the plants.

By the early 1990s, demand began exceeding the capacity of the plants to produce. Aging equipment, built and added in hopscotch fashion with the growing campus, was deteriorating. Pumps worked at cross-purposes and often ran 24 hours a day during summer, further reducing efficiency.

Chlorofluorocarbon refrigerants, or CFCs, used in the plants were outlawed in 1995 and downtime for repairs and maintenance was becoming more frequent. And there was no central control in place to balance the operations.

In addition, the system went through thousands of gallons of water each day during the summers with no good idea of where it was going. Utility costs to power the system also continued to spiral upward.

In 1994, Gordon Bush, a staff technician in UA utilities management and services, part of Facilities Management, was put in charge of renovating a system near the verge of collapse. Bush broke the job down into phases that would take several years and about $65 million to complete and would impact every part of the campus, University Medical Center and surrounding areas.

"We started out way behind," said Bush, who has been at the UA for 34 years. "Texas A&M University, the Pentagon and a number of other good people were doing good things, so we stole their ideas and improved on them."

Bush started with a study of the entire system in order to justify a multimillion-dollar renovation to Joel Valdez, senior vice president for business affairs, and Albert Tarcola, assistant vice president for facilities management. Since most of the funding used for the projects was borrowed, Bush said he needed to show that the improved cost of operations would justify the upfront cost of the renovations.

"We had to do calculations for every project – what the cost would be and what the payback would be – because it was critical for continued administrative support. So, we do our homework before we do anything," he said.

This included upgrades to the University's entire utility grid, including steam and electrical generation as well as chilled water. Time was a factor not only because of rising energy costs but also because the UA was in the process of adding 2 million square feet to the campus footprint.

Tarcola said upper management allowed Facilities Management to "open the box" and look at available new technologies and rethink the way utilities were generated, distributed and maintained. FM responded by building credibility with each project. Equipment and vendors also were chosen based on reducing and standardizing maintenance and the long-term economic life of the systems rather than the lowest upfront costs.

Crews replaced outdated chillers and cooling towers and installed larger chilled water pipes and other equipment to expand capacity and reduce the demand for energy during the day when costs were more expensive.

The chiller plants were shut down during the winter months when demand for chilled water was low, but not without some risks. Some areas, such as laboratories and the hospital, require manageable temperatures for their own operations regardless of the time of year, so scheduling the system renovations was critical to avoid problems.

Bush said just as importantly, UA department representatives were brought in on to offer feedback and are still consulted on a regular basis.

One example where that was helpful was trying to explain how 30,000 to 40,000 gallons of water ended up missing every day. To find out, Bush's unit injected a harmless blue food color into the lines and asked the campus to report seeing any blue water.

A call came in to report blue water coming out of a shower in one of the larger residence halls. This meant that water that was being chilled to 42 degrees at the cooling plant was sent to the residence hall, where it was then heated to 120 degrees for the showers, and then dumped into the sewer. Bush said that single repair alone saved a significant amount of both water and energy.

Crews also installed a new control system, essential to monitoring the campus's three plants. It, along with the upgraded system, allows any of the three plants to shut down for maintenance without disrupting service to campus.

A new thermal storage system was built to reduce peak demand levels. The thermal storage system makes ice overnight when energy costs are lower, and the melted water goes into the chiller pipes.  An education program was developed for facilities management staff that teaches best operating practices, like preventive maintenance and cleaning coils on building air handlers.

The result of the long-term effort has been to flatten energy costs that had been rising since the 1950s. Bush said utilities management and services continues to look for ways to improve.

"That's one of our big jobs. We meet regularly to try to stay ahead of the campus because our lead time is a couple of years. If we want to add capacity, we have to start now for two years down the road. And there is always new technology. We're looking at some alternative fuel sources like nitrogen and hydrogen that could increase the efficiency of our boilers," he said.

"Nanofiltration of wastewater is another," said Marianne Deutch, a staff technician in utilities management and services who has been instrumental in the system redesign. "We potentially can take wastewater headed for the sewer, filter it and put it in the cooling towers. This would reduce the amount of wastewater by some 65 percent, saving not only on potable water but sewer fees as well."

For details on the UA's system, read the application for the award.

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