Hydrogen is the most abundant element on Earth. And it's potential as a fuel could revolutionize the energy market because using it doesn't produce any emissions. Zero. Unfortunately, it's lightweight gas and rises into the atmosphere, which means its rarely found in its pure form. And making making it produces emissions.
Erik Koepf, a mechanical engineering PhD student at the University of Delaware, may have found a way to make hydrogen fuel cheaply, using only sunlight, zinc oxide and water.
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He built a device that has a mirror and chamber, which holds the zinc oxide. The mirror concentrates the sunlight into the chamber holding the zinc oxide. The concentrated light is so intense, with temperatures hitting up to 3,500 degrees Fahrenheit, that when it hits the zinc oxide the heat separates the zinc and oxygen, and the zinc becomes a vapor.
In a large facility, the zinc vapor would be added to water, which reacts with it and turns into zinc oxide again, releasing the hydrogen. Koepf's apparatus doesn't perform that second step, which is actually simpler.