A UK consortium is claiming a world first for a prototype hybrid single-decker powered by both diesel and liquid nitrogen.
The CE Power prototype was built at Horiba MIRA near Nuneaton as part of an Innovate UK consortium led by the Dearman engine company and also involving Air Products, Cenex, Coventry University, Manufacturing Technology Centre and the Transport Research Laboratory.
As with hybrid electrics, the driveline uses the liquid nitrogen — stored in a low-pressure insulated cylinder — to accelerate the bus up to 20mph. This fuel is warmed up to the point of boiling, at which point it creates enough pressure to drive the multi-cylinder Dearman engine. The diesel kicks in at 20mph.
The consortium says that, unlike electric hybrids, there is no requirement for batteries, which are likely to require replacement halfway through the life of a bus. It says the liquid nitrogen system will last as long as the bus and does not require the precious metals used in batteries.