As auto and truck manufacturers invest heavily in hydrogen fuel cell transport, they are considering another alternative — hydrogen combustion engines that can replace diesel motors in a broad array of vehicles.
It's not an entirely new idea. Swiss inventor Francois Isaac de Rivaz built a combustion engine powered by hydrogen and oxygen in 1806.
More than 200 years later, Toyota and Cummins are taking another look. BMW dabbled with it more than a decade ago but abandoned the technology to push into battery-electric cars and plug-in hybrids.