The big oil and gov are afraid of Hydrogen Too easy to make and too hard to control
I wouldn't have bothered responding to this old canard, especially from an AC, but my future son-in-law laid this on me during a (very) long road trip. He was convinced that hydrogen must be that Secret That Oil Companies Don't Want You To Know. After all, it comes from WATER, for crying out loud. You can drop a 9-volt battery and get hydrogen, for crying out loud... all we have to do is put that in a car and run it on water, right? Right?
*facepalm*
For those new to the laws of thermodynamics: Hydrogen is combined with Oxygen to form Water, yes. But it takes energy to get the menage-a-trois separated. And the energy required to liberate H2 from that codependent relationship is, by the laws of physics, no greater than the energy you'll get by combining it *back* with O.
My discussion partner said, "That's ok, we'll just have batteries to do the electrolysis." I gently suggested that if you're going to have enough batteries to generate enough electricity to generate enough hydrogen to run a car, you've got enough batteries to generate enough electricity to run a car -- without that lossy "generate hydrogen" step.
To his credit, I think he understood. That's one. AC, here's hoping you're #2.