21, Clark Street New York, Freshwater Group

21, Clark Street New York, Freshwater Group

When the Freshwater Group decided to convert 21 Clark Street into a luxury senior living development, they turned to Ecosystem to improve the heating and cooling infrastructure. The boiler and chiller plant at the 16-story building in Brooklyn Heights, a former hotel and then Jehovah’s Witnesses residence hall, was reaching its end of useful life. In addition, because it formerly supplied heat and cooling to additional buildings, it was significantly oversized for the 21 Clark Street building alone, making it inefficient and in need of a redesign. Following redevelopment into a senior living community, which will have a higher energy use intensity (EUI) than other residential buildings, any inefficiency would be magnified, increasing the financial impact of wasted energy.

While the building was vacant, there was an opportunity to install a new and efficient boiler and chiller plant without the usual challenges of managing potential tenant disruptions. Due to an aggressive redevelopment construction schedule, time was of the essence. In response, Ecosystem guaranteed not only the project cost and incentives, but the date of completion as well.

The project will deliver the required asset renewal, coinciding with the existing redevelopment construction schedule, and it will also provide long-term cost and operational savings thanks to the more efficient equipment and conversion from high-pressure to low-pressure steam. Increased control over heating and cooling will create the optimal living conditions for future tenants required in a high end senior living residence.

  • $3.5M

    Project Cost

  • $50,000

    Garanteed Subsidies

  • 2018-2019

    Project period

Customized Performance Measures


New boiler plant


High-efficiency chiller plant


High-pressure to low-pressure steam conversion