Campus Chiller Plant Upgrades

TiePoint-bkm provided planning, design, and commissioning services to upgrade four chiller plants supporting a campus of more than five million square feet of corporate office and critical operations space in Texas. The project consists of the replacement of chillers totaling more than 15,000 tons, the replacement of pumps and upgrades to the piping distribution system, the full replacement of the building automation system (BAS), and the replacement of eight medium voltage unit substations. Phased design and commissioning were provided to allow for the chiller plants to remain online throughout construction to support the client’s mission.

Retro-commissioning and a life cycle cost analysis were provided during the planning stage to evaluate various upgrade options for each plant. Infrastructure upgrades to the four chiller plants can be summarized as follows:

Plant 1: Five existing chillers were replaced with four 1,500-ton centrifugal chillers. Three chillers were provided at 4,160V to match the existing voltage, and one chiller was provided at 460V with a variable-frequency drive (VFD) to improve operating efficiency. Power is provided to the chillers from the campus medium voltage (13.2 kV) loop through dedicated substations. Each chiller medium voltage substations was replaced, and the medium voltage loop was reconfigured to improve operations. The chilled water and condenser water pumps were replaced and reconfigured into a headered arrangement to improve operational flexibility.

Plant 2: Five existing chillers were replaced with four 1,500-ton centrifugal chillers. Three chillers were provided at 4,160V to match the existing voltage, and one chiller was provided at 460V with a VFD to improve operating efficiency. Power is provided to the chillers from the campus medium voltage (13.2 kV) loop through dedicated substations. Each of the chiller medium voltage substations was replaced. The chilled water and condenser water pumps were replaced and reconfigured into a headered arrangement to improve operational flexibility.

Plant 3: This plant was expanded to support the Plant 3 and Plant 4 building loads during normal operation. Three existing chillers were replaced with four centrifugal chillers, each with a VFD, consisting of three 800-ton chillers and one 400-ton chiller. A third cooling tower was installed to meet the new demand. The chilled water and condenser water pumps were replaced and reconfigured into a headered arrangement to improve operational flexibility.

Plant 4: The existing water-cooled chiller plant, consisting of three chillers and two cooling towers, was demolished. Two 250-ton air-cooled chillers were installed to provide local emergency backup cooling production.