Oregon State University will continue the development of a microchannel solar receiver, using supercritical carbon dioxide (sCO2) as the heat transfer fluid. The research will resolve key issues associated with the commercial viability of the technology, which allows for a radical reduction in the size of a solar central receiver. The project will culminate in a field test of a commercial scale receiver module with a surface area of approximately one square meter. This project was announced on September 16, 2015 at the Solar Power International conference. Read the press release.
Combining the microchannel receiving panels with the sCO2 heat transfer fluid will make the system about four times smaller than existing technology, which reduces cost, loss of thermal energy, and weight. Altogether, the new system could be about 15 percent more efficient than existing solar thermal approaches to energy production because it will allow the system to operate at higher temperatures and higher pressure.
Oregon State University’s microchannel technology uses extremely small channels and a branching distribution system, both of which speed the transfer process of fluids and improve efficiency. Microchannel lamination technology helps control cost, and short channels help control pressure. The use of sCO2 as a heat transfer fluid is an important element, as it can operate at 650-720 degrees centigrade, compared to 550 degrees for molten salt, which is the current standard.