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The Department of Energy is planning to invest $100 million over the next five years into research for hydrogen-powered heavy-duty trucks.

The outcome could be the development of larger, more efficient and cost-effective electrolyzers that will use a variety of technologies to split hydrogen from water.

The idea is to form two large partnerships that include DOE national laboratories, universities and private companies to help jump-start what has been a very slow-moving American approach to the "hydrogen economy."

It is a concept focused on emissions-free energy that began with discussions in the United States as early as 1966. But commercialization efforts during the past decade have been led by Japan, China, France and other European nations.

In 2003, President George W. Bush tried to awaken the nation to the energy possibilities in hydrogen — the world's lightest, most abundant element. In his State of the Union speech in January 2003, he noted that a fuel cell using hydrogen and oxygen "generates energy, which can be used to power a car producing only water, not exhaust fumes."

A "new national commitment" to use it, Bush predicted, would mean that "the first car driven by a child born today could be powered by hydrogen and pollution-free."

That created a stir of interest but not a national commitment.

That child — who would now be 17 — would be hard-pressed to find a fuel-cell-powered car, let alone a place to refuel it. There are estimated to be 8,000 fuel-cell cars in the United States. Most of them were made in Japan, and most of the 50-odd stations that sell hydrogen fuel are in California.

As for fuel-cell-powered trucks, "nothing from the U.S. is on the road right now," explained Adam Weber, who leads DOE's fuel-cell truck commercialization program at the Lawrence Berkeley National Laboratory in Berkeley, Calif.

He estimates there will be a "fair amount" on the roads within the next five to 10 years because more states are trying to follow California's commitment to emissions-free vehicles. Heavy trucks, Weber believes, will also help make fuel-cell cars more commercially viable.

Because hydrogen fuel weighs much less than electric batteries, it could make trucks more efficient because they could carry more cargo, refuel more quickly and drive longer distances.

The only tailpipe emissions are water; that could help make hydrogen trucks attractive in states that outlaw idling by diesel trucks. Moreover, Weber said in an interview, the resulting electric truck engines will require less maintenance because they have fewer moving parts than diesel engines.

The goal of Weber's research program is to help truck manufacturers make prototypes with more durable fuel-cell technologies that could have a lifetime of a million miles on the road. A side benefit, he predicts, will be more hydrogen-fueling stations for cars and trucks across the United States.

The new DOE approach that focuses on the seeming technology magic of hydrogen may also work to fill in the gaps being created by states like California that are mandating ambitious clean energy goals. In California's case, that means emissions-free new cars and trucks by 2036 and 100% clean energy by 2045.

There is still a long road ahead. According to DOE, 95% of the 10 million metric tons of hydrogen currently produced in the United States. annually is made from reacting natural gas with steam. The resulting hydrogen is used commercially to make fuel in oil refineries and to create ammonia for use in fertilizers.

But hydrogen can also be made with electrolyzers, devices that can use electricity from solar and wind power to split hydrogen out of water.

One of the commercial uses for hydrogen that DOE intends to encourage is the generation and storage of energy, which can be converted back to electricity through conversion in a fuel cell or burned in place of natural gas to make electricity.

This hydrogen, sometimes called "green hydrogen," can be stored for months in underground reservoirs — used today to keep natural gas — and can then be reconverted into electricity, a process that some experts call "power to gas to power."

The storage process will likely be crucial for California, which will mainly depend on solar and wind power to reach its clean energy goals. Nathan Lewis, a professor of chemistry at the California Institute of Technology, has concluded that renewable energy may satisfy as much as 80% of the state's power needs.

But after that, the variability of wind and solar could create what he calls energy "resource droughts," which might require shipments of electricity from out of state.

"You would have blackouts," Lewis recently explained at a forum held by the California Hydrogen Business Council. "Wildfires might give you additional droughts," he added.

He and other experts have noted that the cheapest way to fill the gaps would be to store green hydrogen. It would be much cheaper and more effective than buying large lithium-ion batteries or building solar farms across the state, he said.

Keith Wipke, manager of DOE's new fuel cell and hydrogen technology program, explains that the goal is to help companies make electrolyzers that are more efficient, cheaper and durable than today's machines.

The goal is to make their "green" hydrogen more competitive with the hydrogen made from natural gas.

After that, he explained in an interview, the next step would focus on extending hydrogen into other uses including truck fuel and enlarging the energy storage market.

"If we get electrolysis cheap enough, then you can start to compete with natural gas for making hydrogen at large scale," Wipke said, referring to hydrogen made with renewable electricity.

The research, he hopes, will provide technologies for bigger and better electrolyzers that can supply utilities and truck and car refueling stations. There will be other transportation needs. San Francisco is about to get its first fuel-cell-powered ferry boat, and China and Germany have recently developed fuel-cell-powered trains.

Japan, whose commitment to hydrogen may be the most ambitious, is planning an Olympics for next summer where athletes will be driven around in fuel-cell buses and live in a village powered by fuel cells. Some of the energy may come from Australia, where companies are planning new exports of green hydrogen made from its abundant sunshine to help power Japan.

All of this may still sound dreamy to some, or like green washing to others, but DOE points out that after six decades of discussion, the "hydrogen economy" may finally have enough energy to take off in the United States.

According to DOE, the current price for green hydrogen is somewhere between $5 and $6 per kilogram. The aim is not to invent exotic new technologies, but to give existing technology a push with the hopes of driving its price down to $2 per kg.

Green hydrogen is still a lightweight in the U.S. energy industry, but it has the potential to become a powerful mover. According to DOE, 1 kg of hydrogen has the equivalent amount of energy provided by 1 gallon of gasoline.

Reprinted from Climatewire with permission from E&E News. E&E provides daily coverage of essential energy and environmental news at www.eenews.net.