Sandia Labs: Underground Geologic Formations Hold Future Of Hydrogen Storage

I have to agree. While it will be a long time before enough hydrogen-powered cars make such storage necessary, the sheer effort of manufacturing enough cubic footage of hydrogen to fill such a reservoir would be incredibly expensive in both energy and in obtaining source materials from which to crack the hydrogen. Electrolysis is the best-known method for example, but the "waste product" is oxygen, which could upset the global atmospheric balance as badly as CO2 is doing now but in other ways. Cracking it from natural gas or coal is supposedly more efficient, but still energy intensive and offers a completely different set of waste products that may or may not be useful in the production of other things. In other words, claiming that hydrogen is a safer and better fuel than raw electricity itself is so narrowly focused that it ignores any and all peripheral effects. And those who argue that raw electricity still has to use fossil fuels to run the generators ignores the fact that you still have to use that SAME fossil-fueled energy to crack the hydrogen from that same source--multiplying the rate at which we would consume that source while also ignoring the fact that solar, wind and tidal generators are coming online at an increasing rate to replace those fossil-fueled generators going off-line. As such, is hydrogen REALLY the answer, or just another stop-gap as BEVs continue to improve?

@Vulpine The big problem for BEVs is the battery. IF they can figure out how to make a battery with range and recharging time that approach the magic fuel (gasoline) in convenience, BEV will win out. But if we still don't have that in 20 years, I won't be surprised. The notion that oxygen could become a pollutant of hydrogen production is an interesting one...

@Vulpine Would the problem of excess oxygen exist? Isn't oxygen consumed when the hydrogen fuel is utilized, thus making it a zero sum game?

@Exfordtech Exford - Correct, the Fuel Cell consumes O2 from the atmosphere and combines with the H2 to form water - without getting into it too much, yes - it's a "zero-sum" game if the source of the H2 is the electrolysis of water, (Next: Assumptions) but if the source is cracked natural gas, then it's a lot worse, as oxygen would be consumed in that cycle, as well as CO2 being released from the cracking. Which is why getting H2 from cracking nat gas is a stinky idea.

@shaker Especially since nat gas already works so well in a combustion engine. Burns clean. Just need a safe and effective way of carrying it in the vehicle.

@David C. Holzman Too much oxygen in our air would be as bad as too little. As I understand it, the Oxy-Nitrogen mix needs to stay within about ½% to 1% of current levels or a significant measure of our oxygen-generating plant life will suffocate. You would think the CO2 would help balance that, but it doesn't seem to work that way according to at least a couple studies I've heard about. If you watched the new Cosmos series narrated by Tyson, he covered an entire episode talking about how pollution is affecting our living environment and not just the air. As for the battery question, different reports have it that a surprisingly slight modification to the lithium batteries currently in use by Tesla could double its range AND cut charging time in half--a technology that should be well-enough proven for actual production by the time Tesla's "Gigafactory" partnership with Panasonic is completed. In other words, a matter of two to four years. Well below the threshold you set.

@shaker It's not "zero sum" as there is always a loss of energy in the transfer even if you're using electrolysis. But since electrolysis is also the single most energy-intensive method, it's the least efficient even if it is the cleanest. And yes, the waste gasses and particulates from cracking natural gas or coal are worse as they are much more immediately poisonous. Want to know where the best source of hydrocarbons lies for global use? Try orbiting Jupiter where there is a moon with oceans of hydrocarbons. Try Jupiter itself where the atmosphere is made up of mostly hydrocarbons. If we have no other reason for expanding space flight from Earth, sending out mining ships for raw hydrocarbons and usable minerals would be the most profitable.

@shaker "Especially since nat gas already works so well in a combustion engine. Burns clean. Just need a safe and effective way of carrying it in the vehicle." Problem is, its energy density is significantly below gasoline and diesel. When running on CNG, a gasoline engine loses about 20% of its power and efficiency.