Ultrahigh-Performance Radiative Cooler

6) A radiative cooler, comprising:

• a) a thermally insulated housing, wherein said thermally insulated housing comprises hollow walls, wherein said hollow walls are configured to support a vacuum level of at least 10-5 Torr;
• b) an infared-transparent window, wherein said infared-transparent window is sealably disposed on top of said thermally insulated housing, wherein said infared-transparent window has a transparency in the range of 8-13 μm;
• c) a mirror cone, wherein said mirror cone comprises an open bottom, wherein said open bottom of said mirror cone is disposed on said infared-transparent window and surrounds said infared-transparent window, wherein said mirror cone is configured to reduce downward atmospheric radiation bombarding on said selective emitter;
• d) a selective emitter, wherein a top side of said selective emitter is disposed proximal to said infared-transparent window inside said thermally insulated vacuum chamber housing, wherein said a selective emitter is configured to passively dissipate heat from the earth into outer space through said infared-transparent window, wherein said selective emitter is thermally decoupled from ambient air and solar irradiation but coupled to outer space;
• e) ceramic support pegs, wherein said ceramic support pegs are disposed on an inner bottom surface of said thermally insulated vacuum chamber housing and configured to support said selective emitter;
• and
• f) a sun shade, wherein said sun shade is disposed vertically outside said thermally insulated chamber housing and said mirror cone, wherein said sun shade is configured to minimize direct solar irradiation.

10) A radiative cooler, comprising:

• a) a thermally insulated housing, wherein said thermally insulated housing comprises hollow walls, wherein said hollow walls are configured to support a vacuum level of at least 10-5 Torr;
• b) an infared-transparent window, wherein said infared-transparent window is sealably disposed on top of said thermally insulated housing, wherein said infared-transparent window has a transparency in the range of 8-13 μm;
• c) a mirror cone, wherein said mirror cone comprises an open bottom, wherein said open bottom of said mirror cone is disposed on said infared-transparent window and surrounds said infared-transparent window, wherein said mirror cone is configured to reduce downward atmospheric radiation bombarding on said selective emitter;
• d) a selective emitter, wherein a top side of said selective emitter is disposed proximal to said infared-transparent window inside said thermally insulated housing, wherein said a selective emitter is configured to passively dissipate heat from the earth into outer space through said infared-transparent window, wherein said selective emitter is thermally decoupled from ambient air and solar irradiation but coupled to outer space;
• e) a plate heat exchanger, wherein said plate heat exchanger is in contact with a bottom side of said selective emitter, wherein said plate heat exchanger comprises an inlet pipe and an outlet pipe, wherein said inlet pipe and said outlet pipe are configured to pass and cool a fluid into said inlet pipe and out of said outlet pipe;
• and
• f) a sun shade, wherein said sun shade is disposed vertically outside said thermally insulated housing and said mirror cone, wherein said sun shade is configured to minimize direct solar irradiation.