Hybrid solar concentrator utilizing a dielectric spectrum splitter
View Patent ↗A hybrid solar concentrator that utilizes one or more dielectric mirrors to isolate components of the solar spectrum compatible with specific PV band-gaps and to pass longer wavelengths through to a heat receiver, generating both electricity and heat from a single set of dual-axis heliostats.
1. An apparatus comprising:
a hybrid solar concentrator comprising:
a heat receiver;
one or more dielectric mirrors to isolate components of solar spectrum compatible with specific PV band-gaps and to pass a selected range of wavelengths through to the heat receiver, generating both electricity and heat from a single set of dual-axis heliostats;
a first compressor in communication with a first power source and configured to operate within a first temperature range;
a compressed gas storage unit in fluid communication with the first compressor;
a second compressor in communication with a second power source and configured to further compress gas received from the compressed gas storage unit in the presence of a phase change material, the second compressor configured to operate within a second temperature range larger than the first temperature range;
a first expander configured to expand gas received from the second compressor in the presence of a supercritical phase change material heated by a thermal energy source comprising the heat from the hybrid solar collector, the first expander configured to operate within a third temperature range; and
a second expander configured to further expand gas received from the first expander in the presence of a phase change material, the second expander configured to operate within a fourth temperature range larger than the third temperature range.
2. An apparatus as in claim 1 wherein the compressed gas comprises air, the phase change material of the second compressor comprises water, and the supercritical phase change material comprises water.
3. An apparatus as in claim 1 wherein the first compressor is configured to operate in the first temperature range by injection of a heat transfer liquid.
4. An apparatus as in claim 3 wherein the heat transfer liquid is separated from an output of the first compressor.
5. An apparatus as in claim 1 wherein the first expander is configured to operate in the third temperature range by the injection of a heat transfer liquid.
6. An apparatus as in claim 5 wherein the heat transfer liquid is separated from an output of the first expander.
7. An apparatus as in claim 5 wherein the thermal energy source is in communication with the heat transfer liquid prior to injection into the first expander.
8. An apparatus as in claim 7 wherein the thermal energy source is in communication with the heat transfer liquid via a thermal store.
9. An apparatus as in claim 5 wherein the supercritical phase change material comprises water, and the thermal energy source comprises a salt mixture having a melting point below a bottom point of the third temperature range.
10. An apparatus as in claim 1 wherein the first power source comprises electricity from the hybrid solar collector.
11. An apparatus as in claim 1 wherein the second power source comprises electricity from the hybrid solar collector.
12. An apparatus as in claim 1 further comprising a liquid injector positioned between the compressed gas storage unit and the first expander.
13. A solar energy conversion system comprising:
one or more heliostat mirrors having two-axis trackers, focusing sunlight onto a central tower;
one or more dielectric mirrors near a focal point, allowing a first range of wavelengths to pass through and reflecting a second range of wavelengths outside the first range;
PV cells converting the first range of wavelengths to electricity;
a heat receiver;
a first compressor in communication with a first power source and configured to operate within a first temperature range;
a compressed gas storage unit in fluid communication with the first compressor;
a second compressor in communication with a second power source and configured to further compress gas received from the compressed gas storage unit in the presence of a phase change material, the second compressor configured to operate within a second temperature range larger than the first temperature range;
a first expander configured to expand gas received from the second compressor in the presence of a supercritical phase change material heated by a thermal energy source comprising the heat receiver, the first expander configured to operate within a third temperature range; and
a second expander configured to further expand gas received from the first expander in the presence of a phase change material, the second expander configured to operate within a fourth temperature range larger than the third temperature range.
14. A solar energy conversion system as in claim 13 wherein the first power source comprises electricity from the PV cells.
15. A solar energy conversion system as in claim 13 wherein the second power source comprises electricity from the PV cells.
16. A solar energy conversion system as in claim 13 wherein the heat receiver is in communication with a heat transfer liquid.
17. A solar energy conversion system as in claim 13 wherein the heat receiver is in communication with a thermal store.