Priming the pump for hydrogen fuel

A start-up touting technology developed by NASA's Jet Propulsion Laboratory plans to announce a breakthrough on Tuesday that could make hydrogen fuel a stronger contender in the alternative-energy race.

Ecotality plans to produce a prototype of an apparatus called the Hydratus that generates hydrogen fuel, from a reaction between magnesium and water, as it's needed by a vehicle's fuel cell.

The Jet Propulsion Laboratory, run for NASA by the California Institute of Technology, has developed a new version of the Hydratus that offers double the mileage of the old version, but at the same weight and volume. Ecotality, based in Scottsdale, Ariz., plans to unveil its prototype by the end of 2007, which will give the company time to put refinements into the newer version of Hydratus, according to Ecotality's CEO, Jonathan Read.

"Hydrogen on-demand is going to be what catapults hydrogen from being a great concept to a great reality," said Read.

The Department of Energy has been encouraging research in alternative-energy technologies such as that used in hydrogen fuel-cell cars, whose only byproduct is water. But large-scale implementation of hydrogen fuel faces obstacles that many critics say could be almost insurmountable.

Among the issues: It takes a lot of electricity to produce hydrogen for fuel; hydrogen fuel-cell cars can't go far before needing a refill; the U.S. has no hydrogen fuel infrastructure; and transporting hydrogen safely and efficiently could be tricky. Also, producing hydrogen via conventional means generates a lot of carbon dioxide, one of the primary causes of global warming.

The problem with compressed hydrogen
But Read points out that the product of conventional production and storage techniques--compressed hydrogen--is unlikely to find a viable market anyway. "Compressed hydrogen is the least likely to be the prevailing system when the shakeout is done and over with. It's expensive to produce, transport and store, and it's inefficient in form to produce and store," said Read.

A hydrogen fuel cell vehicle with a Hydratus on board would eliminate the need for producing hydrogen fuel, compressing it for transport and then safely storing it at filling stations, he said.

The details of Hydratus' on-demand fuel production system are proprietary to the Jet Propulsion Laboratory, but Read said that the magnesium/water reaction occurs somewhere between 400 and 600 degrees Celsius. The Hydratus has a cooling system based on the controlled flow of the magnesium, which is also used to continue the reaction.

The device is similar in concept to on-demand electricity producer from start-up Signa Chemistry, which uses a controlled chemical reaction to harvest hydrogen from sodium with silica gel or crystalline silicon powder.

Besides water, a byproduct from the reaction in Hydratus is a powder form of magnesium oxide, which stays in the device until it is pumped out. Filling stations for Hydratus-equipped vehicles would use a three-pronged pump that pumps in new magnesium pellets and water and pumps out the spent magnesium oxide. The pump is safe enough to be used by any consumer, said Read, and takes about 3 to 5 minutes to fill a Hydratus to capacity.

The spent magnesium oxide powder is 99.8 percent recyclable and can be made into usable magnesium pellets at the filling station itself. Though the process for converting the spent magnesium into usable pellets does require electricity, it is far less than the electricity required to produce hydrogen fuel, according to Read. This makes the magnesium a renewable resource.

"Magnesium is the fourth most-common mineral in the world and could be extracted from the sea. It's common and available in almost all countries. The magnesium, once it's put into the system, is a contained system. So there is no need to continue mining," said Read.

Ecotality's Hydratus-equipped buses will offer a range of about 155 miles (250 kilometers), or about 15 hours of operation. The cost for fuel is about $4.80 per liter (about $17.50 per gallon), or $2.80 per liter if the filling station recycles its own spent magnesium.

Because of the limitations on driving range, Ecotality sees municipalities trying to meet clean-energy requirements, and companies with truck fleets such as FedEx, as the most likely early adopters of its technology. The company is already in negotiations with interested municipalities around the world.

Buses equipped with power systems from hydrogen technology company Hydrogenics would, when outfitted with the Hydratus, cost about $500,000 each, whereas a bus with a conventional engine costs about $300,000, according to Read.

The company is also developing other versions of the Hydratus that could be used with fuel cells producing back-up power for houses, cell phone towers and computer systems.