While photovoltaic cells are used worldwide to produce electricity from solar energy, Nico Hotz, an engineer from Duke University has come up with a hybrid solar system to produce hydrogen. His research was funded by the Swiss National Science Fund, while his paper was adjudged as the top paper in ASME Energy Sustainability Fuel Cell 2011 conference in Washington.
The setting consists of a maze of glass tubes with water and methanol. The copper tubes are coated with a layer of aluminum and aluminum oxide. The tubes have nano-particles that are used to carry out catalytic reactions. After the sunlight heats up this combination of water and methanol, catalytic reactions are used to produce hydrogen. This hydrogen can then be stored in fuel cells. The hydrogen produced in this way much more efficient and has lesser impurities. The setup achieved exergetic efficiencies of 28.5 and 18.5, in summer and winter, respectively. The figure stands at 5 to 15 percent and 2.5 to 5 percent for conventional systems in summer and winter, respectively. As compared to conventional systems it absorbs 95 percent of sunlight and very little of it is wasted to surroundings. The set up is able to achieve temperatures beyond 200 degrees Celsius as compared to 60 to 70 degrees Celsius for solar collectors. The total installation costs for the set up are around $7,900, which is less than conventional solar equipment, but higher than conventional fossil fuel generators.
In this age of energy crisis solar energy is certainly the future. In future hydrogen is expected to join electricity as a major energy carrier. It has an important advantage of ‘zero emissions’. Technologies like this present to us new ways to utilize solar energy to meet our current energy needs.
Via: Duke University
