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I’ve seen it claimed that hydrogen is the renewable energy option backed by fossil-fuel interests precisely because it’s impractical. That way, it consumes funding and interest that would otherwise be spent on electrification, without threatening the dominance of fossils.
It also can partly re-use natural gas infrastructure, allowing them to exploit existing capital.
@WaterWaiver @AllNewTypeFace There's a perception that we could just reuse existing methane gas (i.e. "natural gas") infrastructure for hydrogen. But often that just isn't the case:
"The pipelines that transport hydrogen are made of the same basic material as most of those built for natural gas: steel. But hydrogen is a much smaller molecule than methane, the main component in natural gas. In fact, hydrogen is the smallest molecule on Earth. Its size means it can squeeze into tiny spaces in certain steel alloys in a way that natural gas cannot. That can cause “embrittlement,” making the metal more likely to crack or corrode. Hydrogen molecules are also much more likely to leak from valves, seals, and other connection points on pipelines (which risks undermining green hydrogen’s climate benefits). And hydrogen is transported in a more pressurized state than natural gas, which puts more stress on the pipeline carrying it.
"Rather than transporting 100 percent hydrogen, many companies are now testing whether they can blend hydrogen with natural gas for transport in existing pipelines. In a study released last summer, the California Public Utility Commission found that up to 5 percent hydrogen blended with natural gas appears safe, but higher percentages could lead to embrittlement or a greater chance of pipeline leaks. Internationally, France places the highest cap on hydrogen blending, at 6 percent, according to the International Energy Agency (Germany allows blending at 8 percent under certain conditions)."
If the aim is to reach net zero emissions by 2050, a 90% or 95% methane to 10% or 5% hydrogen gas blend just isn't that useful for reaching that goal.
(And that's assuming the hydrogen is green hydrogen as well.)
And if a lot of your infrastructure has to be retrofitted anyway, electrification plus renewables plus storage makes a lot more sense in many cases.
There are still use cases where green hydrogen will be useful — international long-haul flights, rockets, some industrial processes, etc. But it's not the best solution in most cases.
#ClimateChange #hydrogen #gas #NetZero #electrification #transport
Thankyou for that info. I knew it was leaky, but I didn't realise that pipeline materials were so incompatible.
@WaterWaiver @ajsadauskas Even if the pipelines were not, as a software engineer I don't get how you get past the incompatible end user appliances in domestic and industrial sectors.
You can get to that 5%, and an ongoing 5% drop is a little helpful, but how do you swap every single gas appliance?
How do you ensure that every single appliance on a network branch is compatible at scale?
You can not do a flag day, surely, but how do you change a stove from one jet to another at the right time?
You're focusing only on (1) consumer usage and (2) fixed pipelines. There is a bigger variety of gas infrastructure than that.
@ajsadauskas
Thanks for sharing this information.
Still it seems to be more economical to use existing pipelines than new ones. Also a polymer coating is an option.
I know I'm late, but I just realised I remember your name from Reddit times and got really excited! Hello!
Theyre not wrong. Gray Hydrogen is made from methane through a process called hydrocracking. This requires that methane and water be heated together to over 1,000 degress celsius in the presence of suitable catalysts to convert methane and water into hydrogen, carbon monoxide and carbon dioxide. It requires a lot of energy and can not convert all of the potential energy of the methane into hydrogen. The only saving grace is that hydrogen can be consumed in fuel cells generating electricity at high efficiency. But that doesnt really make up for the production process or difficulty of storage.
Whhhhhhhy? Just why?
Like esp with hydrogen embrittlement. You are better off just burning the methane (not that I advocate this either, use green hydrogen or fuck off tbh)
That is the point the article and I were making yes.
I'm no big fan of hydrogen fuel vehicles as an alternative to battery-electric, mostly because, as you said, it's difficult to process and store. But with that said, the argument that hydrogen isn't environmentally friendly because gray hydrogen is derived from fossils fuels has always rung a bit hollow to me. Most electricity in the world is also derived from fossils fuels. The advantage of both hydrogen and BEV over gas is that their fuel sources can also be derived using green methods. There's still work to do on the backend to make that happen, but from an end user point of view the transition is seamless.
Blue Hydrogen is the term you are looking for. i.e Hydrogen produced through electrolysis. And this process is less efficient than storing electricity in a battery. Fuel cells are typically in the 50-60% efficiency range and electrolysis is around 70-80%. Batteries are around 90% efficient. So the round trip efficiency of Hydrogen production and conversion back to electricity is 35 to 48%. So youve got a fuel source that converts electricity into motion around half as efficiently as batteries, that requires high pressure and/or low temperature storage, is an explosion hazard and burns with a clear invisible flame that has even less infrastructure than electric cars do. So many things would have to be improved for it to be more viable than battery electric. The transition to Hydrogen for transportation is not "seamless."
Hydrogen is better suited to chemical industries. Trying to shoehorn it into transportation is trying to wedge a square peg into a round hole. Let Hydrogen do what it is best at and let batteries do what they are best at instead of trying to force them into areas of the economy that they have no business being in.
Electrify what you can, use renewable fuels like hydrogen for what you can’t.
Hydrogen buses will have a role, but they’re not in direct competition with electric buses.
There's a few things about this that surprise me:
Melbourne isn't already entirely, or at least mostly, electrified (not just trains, but buses too)
Regional Vic is having all of their buses replaced too. Naturally that's going to exclude vline coaches, but although big cities like Geelong and Ballarat make sense, smaller ones like Portland and horsham feel like much lower priorities to me
They’ll be using this demonstration project to better understand the TCO of the vehicles and situate them in ideal use cases. I don’t expect these ones to stay around in the city.
@Railison @Baku Electric buses should refer to directly electrified buses. The problem with battery powered buses is the weight and cost of the battery. It fundamental dooms that idea to non-viability, and nearly all transit agencies have found them to be nearly unusable once real-world factors are taken into account.
For buses that can't be electrified, it pretty much has to be #hydrogen or some other chemical fuel.