Central Plant Expansion

The University of Houston’s Power Plant has supplied thermal utilities to the campus buildings since the 1940’s. It has been expanded over the years to accommodate growth and equipment has been replaced as needed.

In 2008, UH determined that:

• The current building program will increase the chilled water demand beyond the plant’s capacity
• The cooling towers are at the end of service lives
• Replacement parts for some parts of the electrical equipment are no longer available
• Steam capacity is much larger than necessary and is therefore operating inefficiently and producing higher emissions

UH retained Shah Smith & Associates, Inc. to design an upgrade to the Power Plant, which is the last expansion to this plant, since the building construction has, for the most part, land-locked the plant. SSA prepared a screening study to determine if a satellite plant would be less costly than the plant expansion and upgrade. The result was that the satellite plant would be more costly due to the amount of infrastructure that would have to be built to connect into the existing campus chilled water and steam systems.

The main elements of the project were to:

• Expand the plant to house three– 2500 ton chillers
• Demolish an old chiller that is surrounded by electrical equipment
• Replace the existing wood-framed cross-flow cooling towers with a 75,000 GPM concrete shell cooling tower
• Replace the old electrical equipment
• Replace the two-70,000 lb/hr boilers with three 45,000 lb/hr boilers, which will provide N+1 redundancy
• Expand the existing PLC-based control system

The primary constraint was that the plant must remain operational throughout the project. SSA prepared phasing plans as part of the construction documents that defined what equipment could be removed from service and what had to be operational before the next phase could begin.

All the major equipment such as, chillers, boilers, cooling towers, and pumps were pre-purchased to coincide with the project’s funding. This also allowed the design to be equipment specific. SSA commissioned the central plant systems.

A criterion for the plant expansion and cooling tower was that they boost the aesthetics of the area, since the plant borders a large plaza between the architecture building and the library. To that end, the plant expansion was enclosed by a glass curtain wall with special lighting to accent the mechanical equipment. The cooling tower was covered with brick to compliment the plant expansion and the surrounding buildings. Stainless steel mesh incorporated into the screen wall and special lighting to highlight the falling water inside the cooling tower.

Green Mountain presented the University with a grant to fund UH’s first solar array – a new 15.58 kW AC solar panel.