All-electrics are next in line while hydrogen-fueled vehicles are a few car lengths behind.

FORBES: Hydrogen-Powered Vehicles Could Emerge From Traffic

While the production of hydrogen results in lost energy, Pivovar says that the use of hydrogen in a fuel cell vehicle provides much more oomph than gasoline.

FORBES: Hydrogen-Powered Vehicles Could Emerge From Traffic

The company's U.S. division is working with Wal-Mart to produce 65 forklift trucks that run on hydrogen, while in Germany it's partnering with BMW and a small bus company.

FORBES: European Entrepreneur Of The Week

Even President Obama has nixed federal funding for hydrogen fuel cells, while Ford and Renault recently halted their own programs.

FORBES: European Entrepreneur Of The Week

The 275-megawatt demonstration plant is designed to prove the feasibility of producing electricity and hydrogen from coal, while simultaneously capturing the carbon dioxide and sequestering it in deep underground reservoirs.

ECONOMIST: Tech.view

Engineers have built a contraption of water heater size that strips hydrogen out of natural gas while burning the carbon to provide heat for the home.

FORBES: Engineers Rule

Also a type of electric vehicle, a fuel-cell car takes hydrogen gas and converts it into electricity, while emitting only water vapor.

CNN: Hydrogen fuel-cell cars look to overtake electric autos

Air Products sells gasses like nitrogen, hydrogen, oxygen and helium used in industrial and medical capacities, while Airgas sells gasses as well as wielding products and safety equipment.

FORBES

The resulting hydrogen atoms help to split hydrocarbon molecules, making them more combustible, while the oxygen released goes on to combine with the carbon, ensuring that more of it burns.

ECONOMIST: To make engines cleaner, add H2O

Some of the hydrogen and carbon monoxide created in the process are fed back into the reactor to keep it going, while GreatPoint recovers most of the catalyst from the char and applies it to more coal.

FORBES: Magazine Article