Third Derivative ​​​

Third Derivative, the climate‑tech accelerator founded by Rocky Mountain Institute (RMI), connects startups with investors, corporates, and experts to rapidly scale breakthrough solutions to address the climate crisis.

Howden Foundation is supporting Third Derivative’s field pilot of Passive Daytime Radiative Cooling (PDRC) materials in Ahmedabad, India. PDRC products look like conventional cool roofs, and work by reflecting sunlight. However, they go a step further by emitting heat in a specific wavelength that can go through the atmosphere and into deep space, enabling much stronger cooling without electricity.

The pilot evaluates performance across more than 80 households in heat-exposed urban communities, in partnership with local research institutions and community-based organisations. Technical teams are measuring roof, indoor, and ambient temperatures to generate robust, comparable seasonal datasets across treated and baseline homes.

Extreme heat is an escalating climate risk in India and globally. If proven effective and affordable, PDRC could offer a complementary, low-cost adaptation approach to reduce indoor heat exposure while limiting additional electricity demand. Validated findings will be shared following full seasonal monitoring and analysis.