Composite radiative cooling materials

A method for manufacturing a composite radiative cooling material, the composite radiative cooling material comprising:

• a first layer comprising a reflective material;
• a second layer comprising a porous material;
• and
• a third layer comprising an emissive material, wherein:
• the composite radiative cooling material has a total solar reflectance greater than 85%, and a thermal emissivity greater than 85% in the wavelength range of 8.0 to 13.0 μm;
• the method comprising:
• arranging the third layer over the second layer and arranging the second layer over the first layer.

A method for cooling a load using a composite radiative cooling material, the composite radiative cooling material comprising:

• a first layer comprising a reflective material;
• a second layer comprising a porous material;
• and
• a third layer comprising an emissive material, wherein:
• the composite radiative cooling material has a total solar reflectance greater than 85% and a thermal emissivity greater than 85% in the wavelength range of 8 to 13 μm;
• the method comprising:
• thermally coupling the radiative cooling material to the load;
• and
• causing the radiative cooling material to cool the load based on the total solar reflectance and based on the thermal emissivity.