# US 2009/0260667 A1 · Solar Thermoelectric Conversion > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2009/0260667 A1 - Document ID: US20090260667A1 - Status: Published application - Kind: A1 - Application number: 12/431,052 - Filed: 2009-04-28 - Published: 2009-10-22 - Earliest claimed: 2006-11-13 - Assignees: Massachusetts Institute of Technology - Inventors: Gang Chen; Xiaoyuan Chen; Mildred Dresselhaus; Zhifeng Ren - Web page: https://patentgrep.com/patent/US20090260667A1 ## CPC - H10N 10/00: Thermoelectric devices comprising a junction of dissimilar materials, i.e. devices exhibiting Seebeck or Peltier effects (integrated devices or assemblies of multiple devices H10N19/00) - F24S 20/00: Solar heat collectors specially adapted for particular uses or environments - F24S 23/30: with lenses - F24S 23/70: with reflectors - H10N 10/13: characterised by the heat-exchanging means at the junction - Y02E 10/40: Solar thermal energy, e.g. solar towers - H10N: ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR - F24S: SOLAR HEAT COLLECTORS; SOLAR HEAT SYSTEMS (for producing mechanical power from solar energy F03G6/00) - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract Systems and methods utilizing solar-electrical generators are discussed. Solar-electrical generators are disclosed having a radiation-capture structure and one or more thermoelectric converters. Heat produced in a capture structure via impingement of solar radiation can maintain a portion of a thermoelectric converter at a high temperature, while the use of a low temperature at another portion allows electricity generation. Thus, unlike photovoltaic cells which are generally primarily concerned with optical radiation management, solar thermoelectrics converters are generally concerned with a variety of mechanisms for heat management. Generators can include any number of features including selective radiation surfaces, low emissivity surfaces, flat panel configurations, evacuated environments, and other concepts that can act to provide thermal concentration. Designs utilizing one or more optical concentrators are also disclosed. ## Claims ### Claim at position 1 1-102. (canceled) ### Claim 103 A solar-electrical generator, comprising: a radiation-capture structure having a front surface and a back surface, said front surface being adapted for exposure to solar radiation so as to generate heat; and at least one thermoelectric converter thermally coupled to said structure at a high-temperature end thereof to receive at least a portion of said generated heat such that a temperature differential is achieved across the at least one thermoelectric converter; wherein said radiation-capture structure is characterized by a capture area and the plurality of thermoelectric converters are characterized by a converter area, a ratio of capture area to converter area being greater than about 100. ### Claim 104 (depends on 103) The solar-electrical generator of claim 103, wherein the ratio of capture area to converter area is greater than about 300. ### Claim 105 (depends on 103) The solar-electrical generator of claim 103, wherein the ratio of capture area to converter area is greater than about 500. ### Claim 106 (depends on 103) The solar-electrical generator of claim 103, further comprising an evacuated enclosure, wherein the radiation-capture structure is disposed at least partially in said enclosure. ### Claim 107 (depends on 106) The solar-electrical generator of claim 106, wherein: at least a portion of each of said front and back surfaces exhibits an emissivity less than about 0.1 over a temperature range of about 0° C. to about 1000° C.; and said front surface exhibits an absorptivity to solar radiation greater than about 80%. ### Claim 108 (depends on 107) The solar-electrical generator of claim 107, wherein said solar-electrical generator exhibits a solar energy conversion of at least 4%. ### Claim 109 (depends on 108) The solar-electrical generator of claim 108, wherein a temperature difference between the high-temperature and a low-temperature ends of said thermoelectric converter is at least about 50° C. ### Claim 110 (depends on 107) The solar-electrical generator of claim 107, further comprising a support structure coupled to a low-temperature end of said thermoelectric converter, said support structure comprising: an inner surface adapted to face said back surface of the radiation capture structure, wherein said inner surface of the support structure exhibits an overall emissivity less than about 0.1. ### Claim 111 (depends on 107) The solar-electrical generator of claim 107, further comprising at least one heat-diffusing element disposed between said front and back surfaces of the radiation-capture structure, wherein said at least one heat-diffusing element provides a lateral heat conductivity in the radiation-capture structure having a value greater than about 20 W/m K. ### Claim 112 (depends on 103) The solar-electrical generator of claim 103, wherein the at least one thermoelectric converter comprises: at least one n-type thermoelectric leg and at least one p-type thermoelectric leg thermally coupled to form a junction, wherein each of said legs is characterized by an axial direction, said at least one n-type leg and at least one p-type leg being disposed relative to one another such that an angle between said axial directions lies in a range from about 0 degrees to about 180 degrees; and at least one radiation collector adapted to collect and concentrate incident solar radiation, said at least one radiation collector adapted to direct concentrated solar radiation to the junction; wherein said at least one n-type leg and at least one p-type leg comprise a plurality of pairs of n-type and p-type legs, said n-type and p-type legs of each pair being linearly aligned, and sharing a pair junction; and wherein at least two pairs of n-type and p-type legs share a common junction. ### Claim 113 (depends on 103) The solar-electrical generator of claim 103, comprising: a plurality of the thermoelectric converters thermally coupled to said radiation-capture structure such that each converter receives at least a portion of said generated heat to create a temperature differential between its high-temperature and low-temperature ends; wherein a spatial arrangement of the converters relative to said radiation-capture structure is adapted such that a temperature differential of at least about 50° C. is generated between the high-temperature and the low-temperature ends of each converter in response to incident solar radiation on said radiation-capture structure, the low-temperature ends of said converters being maintained at a temperature below about 90° C. ### Claim 114 (depends on 107) The solar-electrical generator of claim 107, wherein said front surface exhibits a lateral thermal conductivity greater than about 20 W/m K. ### Claim 115 (depends on 103) The solar-electrical generator of claim 103, comprising: a barrier structure enclosing an isolated environment, said barrier structure being at least partially transmissive to one or more solar radiation wavelengths to allow transmission of said radiation wavelengths into the evacuated environment, wherein at least one thermoelectric converter is disposed in said isolated environment; a radiation concentrator optically coupled to said isolated environment so as to direct solar radiation to heat a portion of said thermoelectric converter to facilitate generation of a temperature differential across said converter; and a heat spreader adapted to thermally couple to said at least one thermoelectric converter, said heat spreader adapted to remove heat from a portion of said at least one thermoelectric converter. ### Claim 116 (depends on 103) The solar-electrical generator of claim 103, further comprising: an optical concentrator optically coupled to said radiation capture structure so as to direct solar radiation thereto, wherein said radiation capture structure comprises at least one protruding element adapted to receive at least a portion of the radiation directed by said optical concentrator onto said structure, said at least one protruding element generating heat in response to solar radiation exposure. ### Claim 117 (depends on 103) The solar-electrical generator of claim 103, wherein the radiation-capture structure further includes a solar capture surface to capture solar radiation and to generate heat in the radiation-capture structure; the solar electrical generator further comprising: a solar collecting transmitter closely coupled with the solar capture surface of the radiation-capture structure, the solar transmitter adapted to collect and concentrate incident solar radiation onto the solar capture surface of the radiation-capture structure. ### Claim 118 (depends on 117) The solar-electrical generator of claim 117, wherein the radiation-capture structure comprises at least one protruding element adapted to receive at least a portion of the radiation directed by said solar collecting transmitter from multiple directions. ### Claim 119 A method of operating a solar-electrical generator comprising a barrier structure for enclosing an isolated environment, said barrier structure being at least partially transmissive to one or more solar radiation wavelengths to allow transmission of said radiation wavelengths into the isolated environment, at least one thermoelectric converter, and a heat spreader thermally coupled to the at least one thermoelectric converter to remove heat from a portion of the at least one thermoelectric converter, the method comprising: removably coupling the barrier structure to the heat spreader to enclose the at least one thermoelectric converter in the isolated environment; receiving solar radiation to heat a portion of said thermoelectric converter to generate a temperature differential across said converter; and uncoupling the barrier structure from the heat spreader. ### Claim 120 (depends on 119) The method of claim 119, wherein: said barrier structure has a bulb-like shape; and a radiation-capture structure is coupled to the at least one thermoelectric converter in the isolated environment. ### Claim 121 (depends on 119) The method of claim 119, wherein the isolated environment comprises an environment with lower heat capacity than atmospheric pressure. ### Claim 122 (depends on 119) The method of claim 119, wherein the isolated environment comprises an evacuated environment relative to atmospheric pressure.