Scientists from Tokyo City University are developing an direct-injection hydrogen internal combustion engine (ICE) for heavy-duty trucks and other vehicles.
Hydrogen production plant Image: Praxair |
The team, also working out of Japan's National Traffic Safety and Environment Laboratory, are working on the spark-ignition engine which will deliver a high power output but no Nitrogen Oxide (NOx).
Although hybrid engine technology has been developed for small to medium-sized vehicles, the team believes that a new approach is required for large vehicles to be able to deliver the hauling power required.
The hydrogen ICE is based on a naturally aspirated 4.7 litre Hino unit using spark ignition and water cooling. A turbocharger and intercooler are planned for later in the project. Most importantly, the team has created a high-pressure hydrogen gas direct injector, following common-rail principles which allows compatibility with the diesel unit.
The results so far have produced an engine with negligible NOx emissions and a power output of 100kW with an indicated thermal efficiency of 41%.