Mueller Associates of Baltimore, MD, has been working on a design project that expands Georgetown University's utilities infrastructure with the addition of three 3,000-ton chillers and other upgrades to the central utility plant and distribution systems.

A second major phase of construction has substantially been completed to update and expand Georgetown University's utilities infrastructure. The project, which includes the addition of three 3,000-ton chillers and other upgrades to the central utility plant and distribution systems, was designed by Mueller Associates of Baltimore, MD. The Whiting-Turner Contracting Co. is the general contractor for the work.

Envisioning several years of campus growth ahead, facility executives at Georgetown University first selected Mueller Associates in 1994 to study the aging central chiller plant and develop a plan for near- and long-term infrastructure improvements. A decade later, Mueller's recommendations have enabled the university to enhance system capacity in support of ongoing facility construction, including ambitious new projects in the South Quadrangle area and proposed mid-campus development. "Georgetown University's utilities infrastructure is well positioned to accommodate campus expansion for many years to come," says Mueller Principal-in-Charge Gary Johnson.

A Careful Fit

Georgetown University's prominent urban setting in northwest Washington, DC, has often challenged campus planners to devise creative infill strategies, and the recent infrastructure upgrades proved to be no exception. Mueller's 1994 feasibility study proposed improvements to the existing central chilled water plant and increases to the system's refrigeration capacity. The study included such complex initiatives as the conversion of 12,000 square feet of an existing cooling tower into a new plant addition to house chilled water generating and electrical equipment-work that required the approval of the U.S. Commission of Fine Arts.

Mueller advised removing the university's old cooling towers and converting the brick structure that housed them into a new plant addition that now accommodates the chilled water generating and electrical equipment. "We were able to work within the old, existing brick envelope-that was vital to the success of the project," says Johnson. "It also enabled us to create a phased approach, with new cooling towers located along the grade bank outside of the existing building. Once these towers were in operation, we removed the old towers-all along, the plant continued to operate effectively."

Mueller's feasibility study outlined five alternatives to increase capacity to 12,000 tons. The selected scheme, constructed in 1998, included the removal of the two wood cooling towers, which were replaced by two induced draft, counterflow cooling towers and new condenser water pumps to serve two existing 2,500-ton steam-driven centrifugal chillers. Work also included conversion of the original tower, and the addition of two 2,000-ton centrifugal chillers and two additional cooling towers. Mueller also designed new primary chilled water distribution and condenser water systems, and new substations. A new chilled water distribution piping system provides hydraulically looped distribution serving the west and north sides of the campus.

Under the initial phase, the university also continued to operate two 1,500-ton Carrier chillers, achieving the desired capacity of 12,000 tons. "This approach enabled the university to continue to maintain much of their existing equipment for as long as possible," says Mueller Project Manager Steve Gillis. "Some of the equipment was dated, but it was still running well for the time being. We wanted to optimize their system for as long as possible, and provide the most cost-efficient approach."

Continued Expansion

Georgetown University's continued growth, especially in the South Quadrangle area, has required additional infrastructure expansion, and in 2002, the university asked Mueller to design the additional plant upgrade, which will expand capacity by an additional 4,000 tons. Mueller's approach included the addition of three 3,000-ton chillers and removal of the old steam turbine chillers, which were wearing down after more than 30 years of use.

Work under this latest phase also includes upgrades to the secondary distribution system, and a new electrical system within the plant that will improve the load balancing on the five available Pepco campus feeders.

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