Yesterday, I received an email from Nick Turner who is associated with Pivotal Engineering, Ltd. in Christchurch, New Zealand. Pivotal Engineering has designed a water-cooled, 2-stroke engine that runs on compressed hydrogen gas.
Nick talks about the new Pivotal Hydrogen Engine that his company has developed, “I recently discovered your site and have spend perhaps a little more time visiting than I should have. We are currently promoting our Pivotal engine for use with hydrogen as it has many advantages. Our engine overcomes many of the problems associated with running hydrogen in a conventional engine and we hope to be running it on hydrogen later this year.”
The Pivotal Engine in the photo is a 2.1-liter 4-cylinder engine with shared crankcase. The engine also uses a starter / generator and has an output of around 170 kw, which is similar to a BMW V12 engine converted to run on hydrogen.
The advantages of the Pivotal Engine are low cost, high power density and the elimination of pre-ignition issues that have plagued other internal combustion engines converted to run on hydrogen. On the Pivotal they say that their compact engine is in fact, “…half of the size and weight of a modern four/stroke automotive engine.”
Because of the thermally smooth and fully controlled combustion chamber, the Pivotal Hydrogen Engine is able to employ a more efficient hydrogen / air ratio. And, because each piston is directly water-cool, the chambers can operate at higher and more thermally efficient temperatures.