Hydrogen-burning engines are still in development, but they're certain to take root in the years ahead Spear-heading the push is Toyota, which deployed the technology in a race car in 2021. But this year has seen hydrogen get a boost as Honda, Suzuki and a group of Japanese minicar and motorcycle makers began promoting the clean-burning power concept as a path to carbon neutrality. Hydrogen combustion was even approved for competition at the 24 Hours of Le Mans. Now suppliers such as turbocharger giant BorgWarner and piston ring specialist Riken are getting in on the trend. The road to mass production is long, but the first steps are already behind us.