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Kelvin

Retrofitting legacy buildings with clean heating and cooling solutions

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Marshall Cox

Founder & CEO at Kelvin

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Employees 21–50
Headquarters Brooklyn, New York, United States
Kelvin decarbonizes legacy multifamily buildings by modernizing radiator heating systems into efficient, adaptive electrification systems through AI orchestration. The company’s mission addresses 120 million underserved radiator-heated apartments, representing 70 billion square feet and $217 billion in annual energy spend. Because Kelvin’s services directly impact heating costs, owners have a clear incentive to adopt Kelvin’s solutions. Starting with the patented Cozy smart radiator cover, Kelvin delivers 25% - 40% cost savings with no upfront CapEx via a $100M debt facility.

Notable Achievements

  • Installed 10,000 units in 2025.
  • Operating fully on commercial cashflows since Mar 2025.
  • 80% of customers are low- to moderate-income communities.

Currently Operating in One Region

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