Note: This is the second story in a two-part series. The first part, "Inside Toyota's quest to future-proof itself for the auto industry's 'life-or-death battle,'" can be read here.

TOYOTA CITY, JAPAN — When Yoshikazu Tanaka punched the accelerator, the blue sedan responded, zooming past neat houses and stores, up lush, green hills and down into lines of cars snaking back from stoplights. The sun shined, a light breeze ruffled leaves on the trees.

The only thing missing was the roar of an engine.

It may have been a hushed experience, said Tanaka, the car’s chief engineer, as he navigated the streets of his hometown, but he said he’d tried his best to make it enjoyable nonetheless.

“We wanted to make it fun to drive,” he said.

The car was a Mirai powered by hydrogen, much like a similarly quiet semi truck that recently made a stop at Toyota's North American headquarters in Plano. You won't spot either of them on Texas roads any time soon.

Still, Toyota hopes the Mirai in particular will help make the zero-emission technology that powers it a lot more ubiquitous. Like, Prius ubiquitous.

The fuel cell-powered Toyota Mirai has an estimated driving range of 312 miles. (Toyota)

Hydrogen-powered vehicles is one way Toyota — one of the largest employers in Plano — is seeking to disrupt the auto industry as it faces an uncertain future.

“The reason we chose a sedan as the fuel cell vehicle ... is that it should not only be friendly to the environment,” Tanaka said in an interview, “but for people to really enjoy the benefits of the technology, the vehicle should be a pleasure to drive.”

Toyota executives and experts have extolled the possibilities of a hydrogen-fueled future, in which vehicles leave behind only small amounts of water instead of damaging emissions, and refilling doesn’t involve plugging your car into a charger for hours at a time. Instead, they use hydrogen fuel, which drivers can get at special filling stations.

That’s a key difference between hydrogen fuel cell cars and purely electric vehicles, like Teslas.

Skeptics largely dismiss hydrogen fuel cells as a technological blip — a short stop on the long march to a sustainable future. Controversial Tesla founder Elon Musk has loudly trashed hydrogen, calling the fuel cells, "fool cells," and "incredibly dumb."

Musk’s distaste notwithstanding, Toyota officials have said hydrogen has an important role to play in broader efforts to make cars efficient everywhere in the world — not just the U.S.

While plug-in electric vehicles might seem like an obvious choice for much of the developed world, physical fuel could be a better option for places where the electric grid is less than reliable.

By 2025, Toyota hopes to have some kind of electrified version of all of its cars — which could include a fully electric plug-in vehicle, a hybrid, or a fuel cell vehicle. By 2030, it plans for more than half of its cars to be electrified.

Part of that is contingent on Toyota’s ability to scale up production of the hydrogen fuel cells it uses in Mirais.

Taiyo Kawai, who leads Toyota’s hydrogen fuel cell development, said manufacturers like Toyota don’t have as much experience making things that involve complex chemicals like fuel cells stacks.

“It’s a big challenge for vehicle manufacturing companies to manufacture chemical products at a high speed and high volume,” he said.

The difficulty is compounded, Kawai said, by pushes to increase the density of power the fuel cells are capable of storing because that means they require smaller amounts of expensive raw materials, which in turn makes the fuel cells cheaper. If power density is higher, the fuel cells also don’t take up as much space in the vehicle.

Then, the Mirais themselves are made by hand on an immaculate assembly line at Toyota City’s Motomachi plant.

Gloved workers in t-shirts that say, “Challenge Zero Emission 2050,” guide hydrogen fuel tanks into place from below the cars. Each car takes an hour to make it from one end to the other, which means that the team of 29 total workers finishes at most nine cars a day and about 3,000 a year.

By 2020, Kawai said Toyota hopes to boost that number to 30,000 a year.

An overhead of the fuel cell system in a Mirai. (Toyota)

That’s compared with the nearby Tsutsumi plant, where assembly lines annually churn out 370,000 cars, including Camrys and Priuses.

Nevertheless, the biggest hurdle to wider adoption has little to do with the technology or the manufacturing. It has to do with infrastructure.

There are no hydrogen fueling stations in Texas. Even in California, where there's an appetite among wealthy drivers to be on the cutting edge, there are just 35 places to fuel up with hydrogen. Another 29 are in the works.

“I cannot say that the Mirai is cool enough yet,” Tanaka said, “but the vehicle should be attractive so more people will want to drive it, and more and more people will say they should establish hydrogen stations.”

For his part, Tanaka said with a grin, he likes the sound of an engine and the feel of guiding a sports car up a winding mountain road — his favorites include the Lexus LC 500 and the Toyota 86. The latter is also favored by his boss, Toyota President Akio Toyoda. For the Mirai, something that replicates that feeling is the goal.

Still, environmental advocates said they were encouraged by Toyota’s vocal vote of confidence in hydrogen.

While Honda rolled out its Clarity fuel cell sedan way back in 2008 — long before 2014, when the Mirai was first introduced — experts said Toyota’s ability to will technology into the mainstream is unmatched.

"Even if Honda or smaller companies have plowed the ground, Toyota can commercialize and push forward, and it knows where the market is," said Terry Tamminen, CEO of the Leonardo DiCaprio Foundation and a California environmental protection agency head under former Gov. Arnold Schwarzenegger.

Hydrogen fuel cell technology is underappreciated compared to electric batteries, Tamminen said. In large part, he said, that’s because it’s tougher to efficiently store electricity.

“I do think the future of electric transportation will be hydrogen,” he said. “I think in 10 years we’re going to look back at the battery era the way we look at steam engines — it was a good idea at the time but ultimately not the prevailing technology.”

Earlier this year, Toyota's second version of a hydrogen fuel cell hauler stopped in the Lone Star State on the way from Michigan, where it was built using two Mirai fuel cell stacks, to California where it was set to be used at the ports of Los Angeles and Long Beach.

A hydrogen fuel cell hauler stopped in August at Toyota's North America headquarters in Plano. (Vernon Bryant / Staff Photographer)

Michael Lewis, a scientist at the University of Texas at Austin’s Center for Electromechanics who has studied hydrogen fuel cells, said compact-but-powerful hydrogen fuel cells are even more promising when you think about how much stuff gets moved around the country in trucks that spew pollution everywhere they go.

That’s why air quality tends to be bad near ports, where trucks often spend long periods idling before they drive a few miles to a warehouse or storage facility.

“You can imagine a hydrogen vehicle being perfect,” he said. But once again, infrastructure is a hurdle; big shipping companies need to have enough confidence to scale up their use of hydrogen fuel cell trucks and invest in fueling stations.

At the Motomachi plant, where Mirais are assembled, Toyota is also running a pilot program for hydrogen-fueled forklifts.

Toyota officials touted how the hydrogen is made onsite using biowaste. It takes three minutes to fuel one forklift, compared to eight hours of battery charging for an electric vehicle. So far, there are 22 at the Motomachi plant, with plans to increase that to about 70.

Reporting in Japan was made possible by a fellowship with the International Center for Journalists. Junko Takahashi, a Tokyo-based interpreter for the center, contributed reporting and translation and Tomoko Ohashi, a Nagoya-based interpreter with Inter Group Corp., contributed translation to this report.