Virginia Tech’s Chiller Plant Phase II saves millions in energy costs as construction completes
Virginia Tech’s chilled water infrastructure capital construction project – aimed at improving the energy and operational efficiency of facilities across the Blacksburg campus – is essentially complete.
The Chiller Plant Phase II project included:
- Addition of a new chiller and cooling tower within the southwest chiller plant
- Replacement of two of five existing chillers and cooling towers within the north chiller plant
- Installation of more than 4 miles of new underground chilled water supply/return piping across campus to connect both plants
Most of the new underground piping was extremely large – much of it with a diameter of 30 inches. Additionally, direct chilled water connections to several essential buildings on the Blacksburg campus were included within the scope of this nearly five-year capital project.
While the finished product is mostly unseen, it certainly is felt by most of the university community. The Chiller Plant Phase II has improved air conditioning systems for many buildings on campus. The chilled water network provides cold water to air handling units in buildings across campus to provide air conditioning. After passing through these air handling units, the now warmer water is recycled back across campus and to the chiller plants for re-cooling and recirculation again back to the buildings.
As part of the project, buildings originally constructed with independent chillers were connected to the chilled water loop and those independent chillers shut down – saving operations and maintenance costs.
Nearly 40 percent of the air conditioned buildings on the Blacksburg campus now are part of the same continuous loop serviced by two chiller plants, providing redundancy.
“The Chiller Plant Phase II project has significantly improved our chilled water infrastructure on Virginia Tech’s Blacksburg campus,” said Dwyn Taylor, assistant vice president for capital construction. “Through the interconnection of the chilled water plants, future maintenance events that require total shutdown of the chilled water network will be substantially decreased, if not entirely eliminated.”
The chilled water infrastructure project is another example of the ways Virginia Tech is striving to meet its Climate Action Commitment goals. The new loop helps foster a reduction in building energy consumption, which helps enable the university’s goal of achieving carbon neutrality by 2030.
"When buildings intended for different purposes are connected to the same loop, you’re able to provide the same cooling to all buildings, with less total energy,” said Paul Ely, associate director of capital construction. “Academic and residential buildings need air conditioning at different times of the day, which means when the coldest level of air conditioning isn’t necessary for one, that energy can be put toward cooling the other.”
Since the Chiller Plant Phase II project began in 2019, electricity consumption for chilled-water generation in fiscal year 2022 fell by 54 percent, when compared to the pre-construction five-year average annual consumption, for a cumulative reduction of 19.6 million kWh. This equates to an energy cost avoidance of approximately $1.8 million.
“The environmental impact avoidances as a result of the Chiller Plant Phase II’s near completion are substantial. Since construction began, it has reduced the output of 8,479 metric tons of carbon dioxide equivalent or 21,046,244 miles driven by an average gasoline-powered passenger vehicle,” said Steve Durfee, campus energy manager. “The Office of Energy Management is operating and monitoring the chilled water system performance to maintain a sustainable, efficient, and effective energy supply for campus customers.”
The southwest chiller plant, finished in 2013, earned a LEED Silver Certification. It was designed with potential for expansion to meet the future demand of new buildings. The western exterior wall of the southwest chiller plant can be easily removed or expanded and has a “green wall” of live, ivy-type plants to help it blend visually into the environment.
