The dream of a global economy fueled by zero emission hydrogen has been met with waves of skepticism. Nevertheless, major auto manufacturers and other stakeholders have continued to forge ahead, and the latest batch of developments is further proof that the dream is edging closer to reality.

1. Hydrogen takes to the road

For those of you new to the topic, liquid hydrogen is known as a rocket fuel, but that's not a particularly practical for earthbound purposes.

For use in vehicles, hydrogen is typically deployed in a fuel cell, which generates electricity through a chemical reaction with oxygen.

The electricity is used to run a generator, so essentially hydrogen fuel cell vehicles are electric vehicles, just like their battery-operated cousins.

One indicator of fuel cell progress involves the different types of the hydrogen vehicles breaking into the market. Here in the U.S., passenger cars have been slow to get off the ground, partly due to cost and partly due to a lack of fueling stations.

In contrast, fuel cell forklifts are beginning to catch on quickly. Warehouse operators find that fuel cells offer the same zero emission, near-silent operating benefits as battery-powered forklifts but with far quicker turnaround time for refueling.

Similarly, trucks could be the next breakthrough, including pickups, delivery vans and semis. UPS is one example. Another is the startup fuel cell semi company Nikola, which recently announced a commitment from Anheuser-Busch for an order of up to 800 hydrogen fuel cell trucks.

Toyota is also deeply invested in fuel cell technology, and just last month the company introduced its new Beta fuel cell semi truck.

Beta is a longer-range version of the Alpha truck launched by the company last year, as part of its efforts to achieve zero emissions throughout its operations at the Port of Long Beach, in California.

2. H2 fuel for a global economy

One key barrier to a sustainable hydrogen economy is the source. Hydrogen is an abundant fuel but it does not have a standalone existence in nature. Currently, most H2 is sourced from natural gas.

Various renewable alternatives are beginning to emerge, such as using landfill gas or biomass, or "splitting" hydrogen from water using an electrical current generated by wind or solar power.

These solutions could be widely applied to generate H2 at or near fueling stations, depending on available resources.

That still leaves the problem of transporting bulk H2 to locations where on-site production is not feasible. It is impractical to transport hydrogen gas without compressing it, and compression involves a great deal of technological gymnastics and, consequently, a great deal of expense.

Earlier this week Australia's CSIRO (Commonwealth Scientific and Industrial Research Organisation) announced one important new development on that score. Instead of transporting bulk H2, CSIRO proposes a system that takes advantage of existing infrastructure for transporting bulk ammonia.

CSIRO's breakthrough involves a new membrane that can be used to separate high-purity hydrogen from ammonia at the point of use.

As for the ammonia, that is beginning to jump on the same futuristic track as hydrogen. Conventional ammonia production is based on a century-old process that is not sustainable, but renewable alternatives are beginning to emerge.

3. On beyond fuel cell vehicles

The U.S. Department of Energy is an enthusiastic backer of the hydrogen economy. The agency has been focusing on fuel cell vehicles, and earlier this month it expanded its "H2@Scale" initiative to leverage the interplay between hydrogen production, power generation and energy storage.

That's not all good news for renewable energy. The new initiative is partly aimed at demonstrating that nuclear and coal power plants can be more economically competitive in the world of low-cost renewables. The idea is that excess, off-peak capacity could be deployed for hydrogen production.

On the plus side, the Energy Department is also aware of the potential for bulk hydrogen production and storage to help integrate more wind and solar energy into the grid:

"The H2@ Scale initiative is looking at ways that hydrogen can help make nuclear and fossil baseload plants more economical, and increase the flexibility and utilization of variable resources like solar and wind . . . Greater use of all of our domestic energy resources increases the nation’s energy security and resiliency."

Through this initiative, the DOE aims to incentivize the research and development (R&D) of transformational technologies that reduce the cost of hydrogen production and distribution technologies, diversify the feedstocks available for affordable hydrogen production, enable new end uses of hydrogen, enhance the flexibility of the electric power grid, reduce emissions through novel uses of affordable hydrogen, generate jobs in growing industries, and provide global technology leadership for export of next-generation energy solutions.

The Department of Energy is actively seeking information on large scale production and multi-sector uses for hydrogen, so if you have any ideas get them to the agency by October 31 and keep the mission in mind:Meanwhile, in terms of scaling up, it seems that Toyota is already one step ahead of the game. Its plans for the Port of Long Beach include a facility that the company is billing as the "first megawatt-sized carbonate fuel cell power generation plant with hydrogen fueling in the world."

With support from the Energy Department and other partners, the new Toyota facility is designed to take in agricultural waste and convert it to water, electricity and hydrogen for use at the port.

Photo: via Toyota.