Might be good for emissions but the mpg claim is hard to believe.As I understand it (happy to be proved wrong):
It uses alot of electricity to get the hydrogen ......that electricity has to come from the petrol engine. Looked at from kj perspective, there's a loss on each conversion. There's no "spare" electricity in a car with an alternator. A current drawn draws power directly from the available hp of the engine. There's a loss involved which the overall system sees. So hard to believe increased mpg. It would be nice to see some evidence.....which would seem to need to break the laws of physics as we understand them today.
Might be brilliant for cleaning up emissions though.
Nick