@Elizabeth Greene

Hi Elizabeth,
i have always understood it that building a hydrogen engine was feasible and had in fact been accomplished in the 1980s but was snaffled by the oil companies to prevent such engines being developed. The issue of charging cars with gas is no longer an issue as many cars have been converted to run on gas (butane i think ?) which would be just as volatile as hydrogen one would imagine.
You appear to speak with a voice of authority on the subject so i'm curious what your credentials are and would very much like to hear your opinion on the retrofit idea i also posed.