Passive Radiative Cooling Film
More than $300 billion is spent per year worldwide on electricity for cooling in applications including refrigeration, air conditioning, transportation, and data centers. The amount of electricity needed for cooling applications is expected to grow an order of magnitude by 2050 due, in part, to expanded air conditioning use in developing countries, increases in electric vehicle usage, and the expected tremendous growth of data centers. Because most electricity is still generated by burning fossil fuels, significant reductions in CO2 generation can be achieved with passive radiative cooling technologies. Currently, 1 gigaton of CO2 emissions annually come from electricity needed for cooling applications. This will grow to greater than 10 gigatons of CO2 emissions per year by 2050 if improved technologies for cooling are not developed.
Project Innovation + Advantages:
3M will develop a film that passively radiates heat away from an engineered surface for use in cooling applications. Using a unique, weather resistant polymer composition, the team will improve the film’s ability to reflect sunlight and ultraviolet (UV) light, thus boosting performance while also increasing its lifespan. This film builds upon radiative cooling technology developed in prior ARPA-E awards to Stanford University and SkyCool Systems, a partner in this project. These cooling films are aimed at reducing electricity consumption for air conditioning, refrigeration systems, transportation, and data centers.
Low-cost, large-scale manufacturing of passive cooling films could lead to significant energy savings in applications including refrigeration, air conditioning, economizers, data centers, cooling towers, and transportation vehicles.
Reducing the energy required to cool buildings and vehicles will (1) lower the overall energy demand from the electrical grid, helping to stabilize demand, particularly late in the day, and (2) reduce energy imports from outside the U.S.
Passive radiative cooling can reduce electricity consumption associated with cooling in buildings and electric vehicles. Decreasing electricity consumption in electric vehicles extends their driving range, which will encourage adoption of electric vehicles and reduce CO2 emissions.
Cooling load reduction in buildings, vehicles, and other applications from the use of radiative coolers can result in significant energy cost savings. In addition, radiative coolers complement other renewable energy technologies, such as solar PV, and can reduce cooling load as solar PV output fades late in the day.