Comment EI/EO is all that matters (Score 1) 141
Most people do not understand that Hydrogen, due to it's inherent instability and desire to chemically change in a volatile manner, is simply an anergy storing devices. Hydrogen is not very energy dense. Understanding it's role is important to determining whether or not to us it as it essentially acts as a battery. If you have X units of energy (electricity), the key question is how many units will you get back out of the hydrogen. So far most the most advanced systems have show that Energy in (Ei) has an Energy out (Eo) roughly equal to Eo = Ei/10. Not anywhere near as efficient as a lithium ion battery. Even lead acid batteries have better performance.