Gas receiver for capturing solar energy
A gas receiver configured to heat a working fluid is disclosed. The receiver comprises an aperture, a light absorber, and a pre-heater interposed between the aperture and light absorber. The pre-heater is transparent to visible light and opaque to infrared. The pre-heater in the preferred embodiment comprises quartz in the form of a plurality of quartz plates or quartz tubes, for example, that are oriented substantially parallel to one another. The quartz plates are separated from one another by a gap to permit air to pass into the receiver cavity, while the quartz tubes are hollow to permit air to pass therethrough. The quartz plates or tubes are configured to transmit visible light from the aperture to the light absorber, and to absorb infrared radiation passing from the light absorber toward the aperture. Since the quartz structures absorb infrared, they serve to capture blackbody radiation emitted from the absorber and use that energy to pre-heat air before it passes into the absorber.
1. A gas receiver configured to heat a working fluid, the receiver comprising:
an aperture configured to allow sunlight and a working fluid to pass therethrough;
a light absorber: and
a pre-heater interposed between the aperture and light absorber;
wherein the pre-heater is transparent to visible light and opaque to infrared.
2. The gas receiver of claim 1 , wherein the pre-heater comprises quartz.
3. The gas receiver of claim 2 , wherein the pre-heater comprises a plurality of quartz plates configured to absorb infrared radiation.
4. The gas receiver of claim 3 , wherein the plurality of quartz plates are oriented substantially parallel to one another and relative to the aperture so that at least some rays of sunlight pass between the plates.
5. The gas receiver of claim 4 , wherein all the plurality of quartz plates are separated from one another by a gap.
6. The gas receiver of claim 5 , wherein the gap between the plurality of quartz plates is sized to permit the working fluid to pass from the aperture, through the pre-heater, and to the light absorber.
7. The gas receiver of claim 5 , wherein the quartz plates are configured to:
transmit visible light from the aperture to the light absorber; and
absorb infrared radiation passing from the light absorber toward the aperture.
8. The gas receiver of claim 1 , wherein the light absorber comprises FeCrAl foil.
9. The gas receiver of claim 1 , wherein the light absorber comprises wire mesh.
10. The gas receiver of claim 1 , wherein the light absorber comprises a ceramic foam.
11. The gas receiver of claim 1 , wherein the working fluid is air.
12. A gas receiver configured to heat a working fluid, the receiver comprising:
an aperture configured to allow sunlight and a working fluid to pass therethrough;
a light absorber; and
a pre-heater interposed between the aperture and light absorber comprising a plurality of plates oriented substantially parallel to one another and transverse to a plane of the aperture, the plurality of plates being configured to absorb infrared radiation, wherein the pre-heater is transparent to visible light and opaque to infrared.
13. The gas receiver of claim 12 , wherein the plurality of plates comprise quartz.
14. The gas receiver of claim 12 , wherein the plurality of plates are separated from one another by a gap.
15. The gas receiver of claim 14 , wherein the gap between the plurality of plates is sized to permit air to pass from the aperture, through the pre-heater, and to the light absorber.
16. The gas receiver of claim 12 , wherein the plurality of plates are configured to:
transmit visible light from the aperture to the light absorber; and
absorb infrared radiation passing from the light absorber toward the aperture.
17. The gas receiver of claim 12 , wherein the light absorber comprises FeCrAl foil.
18. The gas receiver of claim 12 , wherein the light absorber comprises wire mesh.
19. The gas receiver of claim 12 , wherein the light absorber comprises a ceramic foam.
20. The gas receiver of claim 12 , wherein the working fluid is air.