Atwater Apartments

A 130kW cogeneration system fueled by natural gas provides Atwater Apartments, located in Chicago, reliable power while also reducing energy costs.

Quiet CHP system in the heart of Chicago

The CHP system, installed on the roof of the 55-story building, features two iCHP C65 microturbines and new hydronic boilers tied into the existing chilled water piping system. The project had to first remove dedicated year-round cooling equipment from the chilled water loop. This involved adding economizer controls to commercial tenant air handling equipment and reworking the make-up air system to provide residential floors with cooling to spaces with year-round cooling needs. Though the hydronic heating system projects 1,360,000 kWh/year in energy savings, the conversion to hydronic heating would mean that the landlord’s on-site energy bills would increase as the energy usage would shift off of tenant electricity bills and onto the building’s natural gas bills. This is why the owner selected microturbines their high efficiency would help minimize the impact on the building’s energy usage. 

Furthermore, the microturbines would minimize greenhouse gas emissions by utilitzing the microturbines’ waste heat.  To ensure that the microturbines would maximize their return on investment, the equipment needed to operate as close to maximum capacity as possible. This was not an issue on the electrical side, as the building’s minimum consumption rate was well above the maximum electrical output. Similarly, in the heating season, the heating capacity for the building was well beyond the output of the microturbines heating output.

  • Client:
  • Atwater Apartments
  • Industry:
  • Residential
  • Location:
  • Chicago, Illinois
  • System Size:
  • Two C65(130kW)
  • Operating Mode:
  • Grid Connect
  • Controls:
  • BAS
  • Commissioning Date:
  • 2020


130 kW

ComEd Incentive


Yearly Output

1,100+ MWh

Energy Savings

$150,000 per year

Hot Water

860,000 BTU/hr