In 2011, GSA’s Chicago Federal Center joined the green challenge with 6,700 workers. 1 year later, an HVAC overhaul cut natural gas use 25% and saved $140,000 that year

The Chicago Federal Center found a practical way to reduce energy use. GSA upgraded its HVAC system across the large federal complex. The changes included new air handlers, heating coils and fan coil units. Two building automation systems also improved daily operations. Within one year, natural gas use fell 25%. The upgrade saved about $140,000, showing how smarter building management can deliver real energy savings.

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