Building an Energy-Efficient Courthouse
Staff -- Consulting-Specifying Engineer, 11/1/2000
Even with a construction budget of more than $100 million, designing an energy-efficient courthouse may not be an easy job, as a recent project in Florida proves. The new Miami Courthouse delivers conditioned air to more than 516,000-square-feet of space.
The U.S. Department of Energy's (DOE) Atlanta regional office began working to address the energy-efficiency problem during the design phase. Tim Wisner, regional energy coordinator for the General Services Administration (GSA) explains that the performance of new buildings is critical to meeting the Executive Order 13123 goal of 35-percent reduction in energy use by 2010 for GSA's regional property portfolio.
"With the growth we expect in gross floor area in our region, GSA needs to maximize the impact new spaces will have by making our buildings as energy efficient as possible," says Wisner.
Courthouses, which are typically large and complex buildings, present specific difficulties with respect to energy efficiency. They can be more energy intensive than other federal buildings, with their need to accommodate large numbers of occupants. In addition, they are usually located in downtown areas, designed with an expected life of 50 years and created as landmark buildings for the host communities. All of these factors pose energy-efficient design challenges, especially in the Southeast where cooling and humidity control are primary energy loads.
Terry Fuquea, senior project manager for GSA, requested design assistance from the DOE's Federal Energy Management Program, including:
- Whole building energy modeling of the courthouse design.
- Evaluation of a proposal for chilled water instead of a conventional chilled-water system located in the building.
- Evaluation of other design features that would help meet the energy performance goal of 550 megajoules (MJ) per year per gross square meter.
A DOE 2 model was recommended for the project, and during a three- to four-month period, a team of experts worked to develop the model, which was eventually used to provide the project team with a detailed life-cycle cost evaluation of the utility's proposal to supply chilled water from a nearby chilled-water/ice-storage plant.
The DOE 2 model for the Miami courthouse also helped identify design changes in glazing, chiller efficiency, lighting and equipment power density that are estimated to reduce the peak cooling demand from 1,800 tons to 1,200 tons.
For more information about Miami courthouse model project, circle 103 on the Reader Service Card on page 91 of this issue.
