Nanocatalyst Points to Rooftop Solar Production of Hydrogen Fuel
Recent work by a team at Berkeley’s Laser Thermal Lab suggests that solar-powered rooftop systems can generate hydrogen for fuel-cell use on an economic scale.
A paper by Nico Hotz, Heng Pan and Costas Grigoropoulos at Berkeley, with Seung-Hwan Ko of the Korea Advanced Institute of Science and Technology, pointed to solar conversion efficiencies of up to 28.5 percent in summer weather, storing hydrogen for power production at night, or as a transportable fuel.
Now Hotz has joined the faculty at Duke University, where he plans to construct a rooftop prototype of the system.
The technology uses glass vacuum tubes to heat methanol in a matrix of zinc oxide and aluminum oxide, doped with a copper catalyst. At 230°C to 250°C (446°F to 482°F) in this environment, methanol reformulates into hydrogen and carbon monoxide. Efficiency improves with smaller catalyst particles because of their higher surface-to-volume ratio, so the team developed a nanocolloidal matrix with particles smaller than 200 nanometers.
A paper on the Berkeley work won honors at the Energy Sustainability section of the ASME 2011 Energy Sustainability and Fuel Cell Conference in August.— SETH MASIA