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Amalgamated Housing Cooperative

Bronx County

Bronx County highlighted on a map of New York State over a green and white bokeh dot background.
Empire Building Challenge Partner Reimaging Low-carbon Buildings

Oldest limited equity multifamily co-op in the U.S. moves to eliminate carbon emissions with innovative retrofits that make clean energy from dirty water

Amalgamated Housing Corporation’s (AHC) low carbon retrofit project targets two 20-story buildings on their Bronx campus known as ‘The Towers,’ comprising 316 units of limited equity housing.

Amalgamated Housing Cooperative buildings from a distance.


The Towers

3975 and 3965 Sedgwick Ave. Bronx, New York


NYSERDA investment


total investment to install Empire Building Challenge retrofits


of multifamily building stock for potential replication statewide

As part of this retrofit, AHC will focus on re-piping the existing single-use dual-temperature hydronic distribution system to enable simultaneous heating and cooling, rather than the singular seasonal option offered by their present arrangement. If successful, this solution could be replicated in other buildings with central heating and cooling with similar piping systems – a total market estimated at 200 million square feet. Additionally, new wastewater heat recovery and geothermal systems will capture and utilize heat from showers and toilets that is typically flushed down the drain. Thanks to this system design, AHC will reduce the number of geothermal boreholes needed, decommission its cooling tower, and install a photovoltaic system on the roof instead – all further supporting energy generation at the site.

The decarbonization of systems at The Towers will increase thermal comfort and secure utility affordability for their low-to-moderate income residents, as well as enhance the energy efficiency and climate resilience of the property. This project will set a precedent for other large multifamily complexes that share similar ownership structures, laying the groundwork for successful decarbonization in the multifamily sector across New York State.

The Empire Building Challenge

The Empire Building Challenge is a $50 million investment by New York State to demonstrate different pathways for achieving carbon neutrality in tall buildings.

Through the establishment of a private-public partnership with leading real estate owners and their engineering experts, exciting approaches to cold-climate decarbonization are being tested in the New York market.

With the potential to replicate these solutions across the expansive real estate portfolios of Empire Building Challenge partners and beyond, the impact of each project will accelerate New York’s progress toward the Climate Leadership and Community Protection Act’s (Climate Act) goal of reducing greenhouse gas emissions 85% by 2050.


  • Amalgamated Housing Corporation (AHC)
  • Egg Geo


  • Retrofit of heating and cooling distribution systems with efficient motors for fan coil units and shared 2-pipe configuration to allow simultaneous heating and cooling 
  • Wastewater energy transfer (WET) system to recover thermal energy from wastewater lines
  • Ground source heat pump (GSHP) geothermal system
  • Upgraded ventilation system, lighting, and building envelope
  • Installation of ground source heat pumps, solar PV, and controls system
  • Electrification of appliances and submetering

Read about new design approaches for low carbon retrofits.

Visit NYSERDA’s Empire Building Challenge program page or email us at [email protected].