When the University of Arizona embarked on its integration project, it signed up for one tough course in controls, vendors, and protocols. The syllabus also included cogeneration, thermal storage, and even condensate return systems. Show your work by installing metering, then reconcile the BAS with the life safety system for extra credit, and that's the class

Like many other universities around the country, the University of Arizona in Tucson is trying to do more with less. A burgeoning student population is straining the infrastructure of the university at the same time the state keeps cutting funding for higher education. University personnel must be creative in order to maintain the high standards expected by the students and demanded by the community.

U of A officials decided that it could decrease its overhead costs by better managing its energy. This was a difficult proposition, as the university's 450-plus buildings are spread over a wide area and employ devices and systems manufactured by over 35 different vendors. These systems utilize protocols such as ModBus, LonWorks, and Simplex, so it would not be easy to integrate all the energy meters, fire alarm panels, HVAC equipment, and other devices to the BACnet IP network used throughout the campus.

But the university was determined to find a way to manage the campus as a virtual single system, rather than operating each individual building and plant separately. In 2001, U of A embarked on an extensive retrofit and integration project, which would include incorporating the energy meters into the campus Supervisory Control and Data Acquisition (SCADA), which is resident on the BACnet IP campus wide area network (WAN).

The project would also involve integrating the information from all the other systems into the BACnet IP network. In addition, new mechanical equipment and extensive upgrades were made around campus. Three years later, most of the larger buildings on campus have been integrated into the network, and campus personnel are looking to the future to see what changes still need to be made.

CAPITAL IMPROVEMENTS

In 1999, U of A started thinking about how it could better conserve energy, but it wasn't until 2001 that the actual design and implementation began. Originally, the university was just going to convert two proprietary campus-wide energy management systems to a non-proprietary system.

"We analyzed both BACnet and LonWorks at the building level and determined that LonWorks was the right solution at the building level and BACnet was the right solution for the high end. Once we'd established where we were going to go, we were able to convert the two existing systems over to BACnet," stated Joe Branaum, manager of the Integrated Systems Group, Fire Safety and Security Systems Shop, Centralized Computer Command and Dispatch Center, and Facilities Management at the University of Arizona.

Branaum found that one of the benefits of moving to BACnet was the fact that the university can reuse many of its existing sensors. "We're taking some heat detectors from the fire system that gives us real-time data, and we're mapping that into the energy management system. We now have, for example, fire alarm systems that control the air handlers and raised floors. BACnet has given us the ability the reuse whatever has the most intelligence at any given location to get the job done. We can also lose multiple layers of infrastructure and still have everything run as planned."

Analyzing the BAS almost meant taking a look at U of A's three production plants, which generate chilled water, power, steam, deionized water, and domestic water. The analysis showed that changes should be made to the existing plants, so through a request for qualifications, the university chose Trane to upgrade all three plants. Trane uses BACnet as its native tongue, which worked out well with the university's move to a non-proprietary system.

The retrofit involved the installation of new Trane chillers and controls, which were in addition to the university's existing York chillers. Several boilers were removed and some were upgraded, and cogeneration turbines were installed, which produce both power and steam.

"Those turbines have been a big benefit for the university, because we're buying gas for those at a really good wholesale rate, and we're harvesting steam from them," stated Branaum. "We also added an ice plant for thermal storage, so that we can base load one of our turbines all the time by coupling and decoupling the chillers from it, so that we can make ice whenever we need to balance our load, then draw off the ice to help reduce our peak consumption."

TYING IT ALL TOGETHER

Once all the new equipment was in place, the university found that it had no way to quantify any of its money-saving improvements. As a result, the next step involved incorporating real-time metering data into the automation system so that university personnel could better automate plant production and building consumption.