cross-posted from: https://slrpnk.net/post/8569504
How is the hydrogen made?
To save you all a google: it’s made from natural gas, at a pretty significant energy loss compared to just burning the gas. It generates about 4 times more co2 than burning diesel.
Are those CO2 emissions? I don’t get where the CO2 comes from.
I know this is an animation, but it shows pretty well, how hydrogen is made from natural gas. No CO2 emissions. And using the hydrogen should produce H2O.
I think the issue is where the energy to heat the reaction vessel comes from. The video shows green sources, but that isn’t the only way to do it. The thing is, this is ultimately an energy storage tech rather than an energy generation tech. You need excess capacity to make it work, and if that means you have to make up for a shortful with conventional generators elsewhere, you aren’t actually saving anything.
I don’t know if the previous poster is right of course, but the planet is an almost closed system, and there really is no such thing as a free lunch when it comes to energy.
That is true of all colours of hydrogen other than green (and possibly natural stores of ‘fossil’ hydrogen if they can be extracted without leakage).
Green hydrogen is better thought of as a battery than a fuel. It’s a good way to store the excess from renewables and may be the only way to solve problems like air travel.
How hydrogen is transforming these tiny Scottish islands
That’s not to say it’s perfect. Hydrogen in the atmosphere slows down the decomposition of methane so leaks must be kept well below 5% or the climate benefits are lost. We don’t have a good way to measure leaks. It’s also quite inefficient because a lot of energy is needed to compress it for portable uses.
And, of course, the biggest problem is that Big Carbon will never stop pushing for dirtier hydrogens to be included in the mix, if green hydrogen paves the way.
