Get a daily digest of the latest news in tech, science, and technology, delivered right to your mailbox. Subscribe now." energy sources are given prominence to meet net zero emissions targets, a team of MIT researchers has proposed to create completely green, carbon-free hydrogen fuel using a novel, train-like system of reactors powered entirely by the Sun.
According to the team, solar thermochemical hydrogen, or STCH, on the other hand, provides an utterly emission-free alternative since it is powered entirely by renewable solar energy. However, contemporary STCH designs are inefficient: only around 7 percent of incoming sunlight is utilized to produce hydrogen. So far, the outcomes have been low yield and high expense.
In this system, each reactor would initially be subjected to the Sun's heat at temperatures of up to 1,500 degrees Celsius in a hot station. This tremendous heat would effectively extract oxygen from the metal of a reactor. That metal would be in a "reduced" condition, ready to absorb oxygen from steam. To do this, the reactor would be moved to a colder station at temperatures of 1,000 degrees Celsius, exposing it to steam to make hydrogen.
These outer reactors would also include a second sort of metal that oxidizes readily. The outside reactors would take oxygen from the inner reactors as they circled, thereby de-rusting the original metal without needing energy-intensive vacuum pumps. Both reactor trains would operate constantly, producing independent pure hydrogen and oxygen streams.