Three Hydrogen Energy Companies Worth Knowing - SeekingAlpha:

"Debra Fiakas, CFA submits: It is lonely at the top and that is just where Hydrogen sits - at the top of the periodic table. It holds that position with the atomic number one. Unlike glamour elements like gold or silver, Hydrogen rarely gets noticed. It is colorless, odorless, and tasteless. The thing is, Hydrogen is also the lightest element, a gas in its normal state. That makes it highly flammable and dangerous.
Nonetheless, Hydrogen is also the most abundant element in the universe. It is also the friendliest, forming compounds with most of the other elements. There it is in the water we drink - H2O.
Since there is so much of it, Hydrogen cannot be ignored by in the quest for solutions to our looming energy problems. What promise does Hydrogen hold? Quite a few developers think the answer is considerable. There are twenty-five companies with listed securities in our Renewable Energy Index that are pursuing one element or another of Hydrogen as fuel. Most likely there are twice or three times that many private companies in the field. We picked three out of the crowd that either have market-ready products, customers and/or revenue.
The first two are working with Direct Fuel Cell technologies and have found success with “reforming,” i.e. using a fuel processor to convert hydrocarbon fuels into a gas mixture of Hydrogen and other gases. Medis Technologies Ltd. (MDTL) is a bit circumspect on its fuel source, indicating simply that it is a patented proprietary fuel. FuelCell Energy, Inc. (FCEL) uses plain-old pipeline natural gas to set up the Hydrogen/oxygen reaction inside the cell. In contrast, Ballard Power Systems, Inc. (BLDP) produces fuel cells that use Hydrogen as a raw fuel.
Medis Technologies is targeting its Medis 24/7 Power Pack at the market for hand"