Projects

BP’s Westlake 1 is a 29 story office building located on its campus in west Houston. The building was constructed in 1983. The central plant is located in the basement. With the exception of the cooling towers, which had been recently replaced, the major HVAC, plumbing, fire, and electrical equipment is original. Based on the age of the equipment and the long term needs for the building, BP decided to replace the major equipment and obtain redundant electrical feeds to improve reliability.

SSA investigated whether to replace the equipment in the existing basement central plant or locate it in an adjacent parking garage, which was built with space for a future central plant. A previous review by others suggested that routing the utilities from the parking garage central plant and the basement of Westlake 1 was not practical, primarily due to many potential business interruptions. SSA developed a routing for the utilities that mitigated the risk for business interruptions and demonstrated that locating the plant in the garage offered other advantages, which included easier construction, since the new plant could be built while the existing plant remained in operation and locating the plant above the floodplain.

The redundant electrical service will be located in an enclosed space in the parking garage and will consist of two redundant feeders, with each feeder serving two 5 MVA transformers. Relaying provided by CenterPoint will switch all four transformers to the operating feeder in 3 seconds from the loss of the other feeder. Once power is restored on the feeder, a closed transition will transfer two of the transformers back to the feeder.

Chilled water is provided using four 1000 ton chillers in a variable flow primary arrangement. All chilled water and condenser water systems equipment have variable speed drives.

The heating water system uses bent tube water heaters that are rated for the static pressure created by the high rise building. This eliminated the secondary heat exchanger and pumps, which were being used with the fire tube boilers.

The two existing water tanks in the basement which now provide domestic and fire water to the building were separated so that one is dedicated to fire and the other is dedicated to domestic water. Each tank has an internal divider installed to allow maintenance without interrupting service.