Chiller plant gives aging college building new life
Photo caption: Jefferson Community College installed a chilled-water plant with ice storage at its college center in an effort to upgrade cooling capacity without high utility costs.
The James McVean College Center at Jefferson Community College in Watertown, NY, is an important building on campus. The facility houses offices, space for music instruction, a dance studio, dining facilities, a fitness center, the 478-seat Sturtz Theater, and a large multipurpose gymnasium, used for athletics and other events, such as the college’s graduation ceremonies.
While it is a perfect venue for a variety of college activities, the aging McVean Center was in need of serious renovation. Originally built without air conditioning, a combination of direct expansion split systems and window air-conditioning units had been installed in portions of the building over many years. The college wanted to centralize cooling to improve efficiency and increase comfort for its students, faculty and guests, all on a limited budget.
Jefferson Community College consulted with its engineer regarding the needed upgrades. While the college wished to increase its cooling capacity by more than 50 tons, adding electrical capacity would require a substantial, and costly, utility upgrade that could jeopardize project approval. One way to add cooling without extra power: increase system efficiency. In addition, the engineer did not want to place an undue burden on a reduced facility staff. A water-cooled system would require water treatment and additional equipment to be maintained, while an air-cooled system might not be efficient enough. The engineer suggested a chilled-water plant with ice storage and requested competitive bids.
Trane proposed the EarthWise™ Ice-Enhanced Air-Cooled Chiller Plant. Based on previous experience with Trane, both the college and the engineer said they could rely on Trane as a single source for professional consultation, systems, and services. The engineer also gave high marks to the simplicity of the system design. Trane was selected to partner with the college and the engineer on the upgrade.
With a pre-engineered standard system configuration, integrated with a system controller and operator interface, the Trane EarthWise™ Ice-Enhanced Air-Cooled Chiller Plant aims to simplify the design and implementation of a system typically considered complicated. A 90-ton CGAM air-cooled scroll chiller, supplemented by four CALMAC IceBank® thermal energy storage tanks and a Trane system completion module, serve the desired 200-ton peak cooling capacity, with increased comfort and a better learning environment.
The EarthWise Ice-Enhanced Air-Cooled Chiller Plant builds ice at night during off-peak hours when the building cooling and power load is low. Shifting the time when cooling is created allows the college to take advantage of lower-cost, off-peak electricity, as well as milder outdoor conditions for improved system efficiency. During the day, the ice and the chiller work together to cool the facility. The ice tanks and the downsized chiller help the college manage peak electrical demand and avoid a costly substation upgrade.
Building operators use a Tracer™ SC controller to manage the EarthWise System. With a click of a button, facility managers can monitor equipment, make set-point changes, manage alarms, and decide whether to melt, make or preserve ice. According to Trane, its Tracer SC dashboard screens make reporting and programming adjustments simple, at a workstation or with remote access via devices such as smartphones or tablets. The campus uses Tracer ES™ software to integrate the variety of control systems currently in use at the college and help them make enterprise-wide decisions.
The Trane EarthWise Ice-Enhanced Air-Cooled Chiller Plant has allowed the Jefferson Community College to nearly double its cooling capacity while decreasing utility costs. The system provides the college with load shifting flexibility to help manage peak demand, avoid a costly electrical substation upgrade, and take advantage of lower cost off-peak electricity. Comfort has been enhanced, and with the chillers working mainly at night and further away from occupants, sound levels have been reduced.
“We haven’t fully tested the chillers to see what kind of loads they can handle. In most instances so far, we have been able to use ice-only to cool the facility,” said Bruce Alexander, director of facilities at Jefferson Community College. “We want any renovation we do to be as green as possible. The EarthWise system is aligned with our green initiatives.”