Anything that has a radiator is blowing off heat and wasting energy doing so. So why not use it to heat up NaOH which will remove the oxygen from it. This leaves you with NaH which when allowed to react with water creates hydrogen. Then you can use the leftover NaOH to do the same path again.
The idea of using NaOH to store hydrogen has been realised. They are called powerballs (http://www.powerball.net) but no concept of using the technology to capture all the energy we throw away through radiators on cars and such has not been used.
Just as a side note that people would probably wanna know about is the implementation of hydrogen onto diesel fueled vehicles as a combustion agent.
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