Hydrogen was once touted as the alternative energy source that would end the civilized world’s dependence on greenhouse gas-emitting fossil fuels. However, while hydrogen is the most abundant element on earth, it is almost always bonded to other elements and large amount of energy is required to obtain elemental hydrogen. This energy requirement has made using hydrogen as a fuel prohibitively expensive. Solar decomposition technology puts hydrogen back on the table as a potential alternative fuel. Solar decomposition technology can take a variety of feedstocks, including fossil fuels, water, and biomass, and release hydrogen and commercially usable carbon-black without producing any harmful greenhouse gases. The resulting hydrogen can be used in internal combustion engines and fuel cells. Additionally, using solar decomposition with a fossil fuel feedstock would prolong the lifespan of the fossil fuels, which would give more time for new alternative power sources to be developed (Ozalp et al. 2009).—Tim Fine
Ozalp, N., Kogan A., Epstein M., 2009. Solar decomposition of fossil fuels as an option for sustainability. International Journal of Hydrogen Energy 34.2, 710-720.
Nesrin Ozalp at Texas A&M University at Qatar, and his colleges at the Solar Research Facilities Unit at the Weizmann Institute of Science in Israel did a study examining the different solar decomposition processes currently available to produce hydrogen.
Solar decomposition technologies are an interesting fusion of conventional and alternative power sources. Using the hydrogen generated by the decomposition reactions would eliminate greenhouse gases from the fuel life cycle, resulting in a huge step towards a carbon neutral economy. However, depending on which solar decomposition technology is used, some CO2 will be produced. The solar decomposition technologies that produce CO2 also produce more hydrogen than those that do not produce CO2. Producing hydrogen without simultaneously producing CO2 represents a tradeoff, less hydrogen for no CO2. The carbon-black—pure carbon—generated by solar decomposition of fossil fuels and biomass is used in the manufacture of rubber, batteries, nano-tubes, polymers, cars, and many other consumer items. Because the carbon produced by solar decomposition is marketable, the hydrogen produced has the potential to compete profitably on a per unit basis with gasoline and the sale of the carbon can offset the costs of using solar decomposition technology. Used in combination with fossil fuels, solar decomposition technology has the potential to prolong the lifespan of fossil fuels—buying time to research a permanent sustainable energy source.—Tim Fine