NAGOYA, Japan -- A sports car developed by Toyota Motor flew across the finish line to become the first vehicle running on a hydrogen engine, and not merely fuel cells, to complete a 24-hour endurance test.
Toyota entered the Corolla Sport into this year's Super Taikyu Series held Saturday and Sunday in Japan's Shizuoka Prefecture, between Tokyo and Nagoya. Unlike most hydrogen-powered vehicles, which employ fuel cells that use hydrogen to generate electricity for motors, this auto ran on a repurposed gasoline internal combustion engine used in the GR Yaris, with some slight modifications.
The auto produced almost no carbon dioxide emissions.
Four carbon fiber fuel tanks stacked to the ceiling occupy the rear of the Corolla. When the vehicle tore down Fuji Speedway at the start of the race on Saturday afternoon, the engine noise was explosive and reverberated through the arena -- but seemed no worse than the conventional gasoline-powered competitors.
But 20 minutes in, the differences were evident. The Corolla was already aside a hydrogen tanker truck for refueling. The vehicle needs to top off more often than the other cars. During the 24-hour race, Toyota's vehicle required 35 fill-ups, compared with around 20 pit stops for other participants.
At six to seven minutes, refueling the Corolla also took longer. The Japanese automaker's hydrogen vehicle ultimately traveled about half the distance and around half the average speed of the gas-powered rivals.
Toyota, which is strong in fuel cell vehicles, will enter hydrogen cars into more races to identify and resolve problems dogging the commercialization of hydrogen engines and make the technology competitive with electric vehicles.
"EVs are taking center stage in electrification, and if everything goes to EVs, then 1 million jobs will be lost in Japan," Toyota President Akio Toyoda told reporters Saturday. Toyoda, himself a racer nicknamed Morizo, participated in the endurance race as a driver.
"We must keep in mind that the goal is carbon neutrality," Toyoda said. "I want to show that [hydrogen engines] are an option in motor sports venues."
Toyota has long supported hydrogen fuel cell vehicles as a strategy, rolling out the pioneering Mirai fuel cell car in 2014.
But using a hydrogen engine rather than fuel cells would have certain advantages. Such vehicles would employ conventional engine technology and provide a driving experience similar to gasoline cars. And "it's easy to generate torque at low rpms, making it ideal for trucks," a Toyota executive said.
There are hurdles, though. BMW and Mazda Motor have also grappled with the technology, but the fast combustion speed of hydrogen makes it difficult to control. The autos also require large fuel tanks, meaning that legroom is tight. So automakers have mostly opted for fuel cells, which make more efficient use of hydrogen.
Along with driving range, cruising speed and frequent refueling, hydrogen engine cars face another disadvantage in that they require large fuel tanks that steal legroom. BMW and Mazda have failed in their attempts to develop such vehicles.
But gasoline-powered vehicles draw part of the global blowback against carbon emissions. Honda Motor, General Motors and Volvo Cars have each said they eventually will abandon production of gas-powered autos. Toyota looks to develop hydrogen engines as a real carbon-free alternative.