EROS Data Center, Mundt Federal Building, South Dakota

The United States Department of the Interior
U.S. Geological Survey Central Region
EROS Data Center, Mundt Federal Building
Sioux Falls, South Dakota

The EROS Data Center, located in the Mundt Federal Building in Sioux Falls, South Dakota, has been selected as a 1997 Federal Energy Saver Showcase. The 221,795-square-foot building is implementing various energy conservation measures.

Energy Efficiency Features

Two 23-year-old, 250-ton chillers, which require 86 kilowatts (kw) of power per ton of chilled water, will be replaced with two 300-ton chillers. The new chillers require only 6 kw of power per ton. The warehouse heating system will be replaced by natural gas heating. A 13-year-old, 500 kw power supply operating at about 60% efficiency will be replaced by a 500-kw, parallel-staged, rotary central power supply that will operate at 85% efficiency.

Sixty percent of boiler water and cooling-tower chemicals, totaling over 5,000 gallons per year, goes down the drain during "blow down" to dispose of accumulated Total Dissolved Solids (TDS). Most of the TDS is removed by reverse-osmosis, where 60% of the chemicals are recovered. The Data Center plans to install a new set of reverse osmosis membranes and improve pre-filtration for the existing water reclamation system. Fuel oil burners in the boiler will be replaced with dual natural gas and fuel burners. Various lighting modifications will be made including retrofit of outdoor lighting, resulting in load shedding, relamping of outdoor lighting, installation of alternative switching for crawl-space lighting, and retrofitting lighting fixtures in the data-handling area with energy-efficient lighting.

Currently, the EROS Data Center at the Mundt Federal Building is metered for electricity, fuel, oil, diesel, and kerosene usage. The facility is actively seeking assistance in implementing additional water conservation measures and using renewable energy resources.

Project Cost and Savings

Total cost for the chiller replacements was $130,000, and funding is mandated by Federal chlorofluorocarbon emissions requirements. The new chillers will save 131,400 kw, for $4,200 in annual savings. The new power supply installation will save roughly $40,000 annually for the EROS Data Center. Total project cost is $325,000 with a projected payback period of eight years. The fuel oil burner replacement will cost $16,000, but annual savings are estimated at $8,000, with a simple payback period of two years. New reverse-osmosis membranes will cost about $48,600, but they will save the facility 1.44 million gallons of water, $5,400 per year in water costs, and $3,000 in chemical purchases each year.


U.S. Department of the Interior

Greening of the Interior