Facility:

Alliant Energy General Office – Dubuque, Iowa

20,000-square-foot downtown office building.

Geothermal heat pump system:

56-ton system with WaterFurnce and ClimateMaster heat pumps.

Geothermal loop system:

• Open loop to Alfa Laval plate heat exchanger with one 10-horsepower pump.

• Two 7.5-horsepower alternated closed loop pumps.

At a glance:

• All pumps are controlled by variable speed drives.

• Internal loop temperatures are held at 50-65 degrees Fahrenheit.

• Two fresh-air units utilize closed loop coolant to temper incoming air.

• Electric backup used in extreme winter conditions.

• Mississippi River water in aquifer layer filtered via a 14-inch diameter, 20-foot-long stainless steel microscreen.

General design:

Shive-Hattery – Cedar Rapids, Iowa

Mechanical contracting:

Giese Sheet Metal – Dubuque, Iowa

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