Hydrogen and hydrogen fuel cells have opponents and proponents on this site, and many times they are rather vocal. Which is a good thing, I think, because they both raise points and facts that the other side may not have considered.
Zhili Xiao, a physicist at Northern Illinois University, has been thinking about how to minimize the dangers of the hydrogen economy. Even though automakers are working on designing safer hydrogen storage tanks, Xiao and his team have developed tiny sensors that can detect hydrogen when those tanks inevitably leak. This is important, because when the hydrogen concentration of a gas is 4 percent, it can ignite easily if a spark is present, Xiao told the Suburban Chicago News.