Central Chilled Water Distribution - Capitol Complex

State of Illinois

Springfield, Illinois


The State of Illinois Capitol Complex, consisting of thirteen buildings, had a decentralized cooling system that was failing due to age and required replacement. Henneman Engineering recommended construction of a new central chilled water plant that would reduce the State’s energy and operating costs, as well as meet their goals for reduction of CFCs on the campus.


Phase I of the project constructed a new addition to house two 1,100-ton double effect absorber chillers.  Phase II of the project installed an additional 2,325 tons of high efficiency electric centrifugal chillers that utilized R-134a.  Also included in Phase II was the installation of a chilled water distribution system incorporating high temperature differentials and variable flow pumping which distributes cooling to eight buildings. Services provided were engineering and life cycle analysis, equipment procurement, mechanical engineering, controls, electrical engineering, construction observation, and commissioning.

Total Chilled Water Tonnage Installed: 4,525 tons

Completion Date

Total Construction Cost