Everyone knows photovoltaic cells are used to convert sunlight into electricity. Nico Hotz, a Duke University engineer has come up with a novel hybrid system that, according to him, could generate hydrogen by using sunlight.
Instead of a standard solar-powered system, Nico Hotz proposes a hybrid option in which sunlight heats a combination of methanol and water in a maze of glass tubes on a rooftop. After two catalytic reactions, the system will be capable of producing hydrogen much more efficiently, having lesser impurities. The hydrogen can then be used in fuel cells.
“The hybrid system achieved energetic efficiencies of 28.5 percent in the summer and 18.5 percent in the winter, compared to 5 to 15 percent for the conventional systems (PV+electrolysis) in the summer, and 2.5 to 5 percent in the winter,” said Hotz, assistant professor of mechanical engineering and materials science at Duke’s Pratt School of Engineering.
Unlike conventional systems, Hotz’s invention is able to capture 95 percent of sunlight and only a small amount of it is lost. The engineer also explains that the new hybrid solar system can achieve temperatures beyond 200 degrees Celsius. If we make a comparison, standard solar collectors (not concentrated ones) can only heat water between 60 and 70 degrees Celsius.
The system’s installation costs are around $7,900, being much more expensive than conventional fossil fuel generators and less than conventional solar equipment.
[via Duke University]