Solar receiver

A solar receiver for converting solar radiation at a concentration factor of at least 500 into thermal energy, the solar receiver comprising:

• a heat-absorbing solid body comprising:
• a plurality of absorbing elements and at least a portion of each of the plurality of absorbing elements absorbs incident solar radiation in use;
• and
• wherein at least one of the plurality of absorbing elements is formed from a plurality of materials such that the portion of the at least one of the plurality of absorbing elements has different solar absorption and/or reflection properties across a surface area upon which the incident solar radiation is incident in use such that absorptance of the at least one of the plurality of absorbing elements increases along a length of a conduit therein;
• a fluid system to provide a flow of working fluid proximate to the heat-absorbing solid body;
• and
• a movement device to move the heat-absorbing solid body such that one or more surfaces of the heat-absorbing solid body are periodically exposed to the incident solar radiation;
• wherein:
• the incident solar radiation heats at least a portion of the heat-absorbing solid body which in turn heats the working fluid proximate to the heat-absorbing solid body;
• and
• wherein:
• the heat-absorbing solid body is a rotor;
• and
• the movement device rotates the heat-absorbing solid body.

A solar receiver for converting solar radiation at a concentration factor of at least 500 into thermal energy, the solar receiver comprising:

• a heat-absorbing solid body comprising:
• a plurality of absorbing elements and at least a portion of each of the plurality of absorbing elements absorbs incident solar radiation in use, wherein each of the plurality of absorbing elements comprises a conduit, wherein the at least a portion of each of the plurality of absorbing elements comprises an outer portion of each conduit of the plurality of absorbing elements;
• and
• wherein at least one of the plurality of absorbing elements has a surface topography, morphology, or texture different from a surface topography, morphology, or texture of another of the plurality of absorbing elements such that the plurality of absorbing elements have different solar absorption and/or reflection properties and the absorbing element that will experience the greater solar flux when in use has a lower absorptivity, wherein the solar absorption of a first surface of the at least one of the plurality of absorbing elements and the solar absorption of a second surface of the another of the plurality of absorbing elements are each at least 0.5;
• a fluid system to provide a flow of working fluid proximate to the heat-absorbing solid body, wherein the fluid system flows the working fluid through one or more flowpaths in each conduit of the plurality of absorbing element;
• and
• a movement device to move the heat-absorbing solid body such that one or more surfaces of the heat-absorbing solid body are periodically exposed to the incident solar radiation;
• wherein:
• the incident solar radiation heats at least a portion of the heat-absorbing solid body which in turn heats the working fluid proximate to the heat-absorbing solid body;
• and
• wherein:
• the heat-absorbing solid body is a rotor;
• and
• the movement device rotates the heat-absorbing solid body.