Department of Defense (DoD) installations spend billions annually on building energy use, with cooling demands posing a major burden. This demonstration aims to evaluate passive radiative cooling film (PRCF) as a low-cost, energy-efficient solution to reduce heat loads on buildings and strengthen installation energy resilience. The project will install and monitor PRCF on buildings across several installations to compare film and no-film performance using heat-flux, temperature, and ambient condition data. Findings will determine the technology’s effectiveness, scalability, and applicability across DoD facilities.

PRCF is a material that reflects sunlight, allowing the film to be cooler than the ambient air temperature both during the day and night, with no input electricity. The film is most comparable to highly reflective white paints. A typical cool roof coating/white paint will initially achieve between 75 to 85% reflectivity, and after six months, between 60 to 80%. The PRCF is 95% reflective of energy from the sun and can maintain its optical properties over a lifespan of up to 15 years.

Results from a recent bench-scale study performed at Twenty-nine Palms, CA in collaboration with Naval Facilities Engineering Systems Command Engineering and Expeditionary Warfare Center show that the film consistently achieved sub-ambient surface temperatures over a period of two weeks. It can reach temperatures as low as 10°F below ambient conditions even under direct sunlight. The cooling film can be applied onto roofs of warehouses, homes, vehicles, and on exterior surfaces of many other outdoor surfaces that require cooling when exposed to the sun. This technology was initially developed with support from Department of Energy’s Advanced Research Projects Agency-Energy program.

This technology is able to provide passive cooling without using any electricity or water, which is expected to reduce or completely eliminate the amount of cooling capacity which will need to be installed to cool a building. The technology is expected to generate savings by reducing capital as well as operational expenditures. The PRCF will keep roof temperatures lower and target a 50% to 60% reduction in heat entering the building through the roof. This, in turn, will have a significant effect on internal temperatures and energy use for cooling. (Anticipated Project Completion - 2026)