Wow. According to the hydrogen industry lobbyist in my mentions I've gaslit you all by suggesting that heat pumps are great.
Which is weird. Cos heat pumps are an amazing technology. There's even moves to develop air/air heat pumps they use propane as the refrigerant, so DIY installers can easily install them. But what's truly amazing about heat pumps is how they can scale. In the city of London they've installed a big ground source heat pump to drive district heating. It's awesome.
@quixoticgeek Having just read through a Hydrogen Safety data sheet, I'd be very worried about (1) the pipe work, are they replacing all the pipe work with Hydrogen tested pipe, Hydrogen dissolves in many metals and in addition to leaking out, may have adverse effects on them, such as hydrogen embrittlement (2) Hydrogen gas leaking into external air may spontaneously ignite. Hydrogen fire, while being extremely hot, is almost invisible, and thus can lead to accidental burns
@Porcia @quixoticgeek
Yes to all of the above. Long story short, the domestic gas network will never be safe for hydrogen - you’d need to replace all the lines, valves, regulators, monitors. Even then it would be uninsurable, no customer would take that risk.
Insurers will be busy offloading customers in all the new flood risk areas, they won’t want every other district blown to hell.
In addition, H2 is a lot less dense than methane. So to achieve a volumetric density that's similar at the point of use H2 has to be pumped at about 3 x the rate of natural gas. Our existing pumping stations can't do that so their pumps would have to be replaced and upgraded to cope.
@mackaj @BashStKid @Porcia @quixoticgeek it's worse than that. Raw volume isn't what needs to be delivered, energy is. H2 is 9MJ/l Methane is 55MJ/l. So you need to transport SIX times as much to get the same energy to your destination.
@SkipHuffman @mackaj @Porcia @quixoticgeek
Sounds about right. I think even in a best comparative case, if the HP gas network is running at ~100 bar, there’s no way in hell it could operate at 600 bar to get a similar throughput energy density. Even less likely for the LP distribution network with poly pipe in it.
@BashStKid @SkipHuffman @mackaj @Porcia UK mains gas pressure is something closer to 25mbar...
@BashStKid @quixoticgeek @SkipHuffman @Porcia
You good folks may appreciate scanning this document:
"The Techno- Economics of Hydrogen Pipelines"
It's specific to Canada but discuses many of the issues and limitations we've been chatting about in depth, especially section 4.2.
If they're right then a hydrogen pipeline could only deliver a maximum of 88.4% the energy of an equivalent methane pipeline.
@mackaj @quixoticgeek @SkipHuffman @Porcia
Thanks for that.
For sure there will be an industrial hydrogen system for use (eg green steel) or storage (eg salt caverns).
Unlikely big H2 customers in same place as power gen (hydro, wind, wave, solar) so you either have a power network or a H2 distribution network.
Or a lot of H2 gets turned into ammonia for feedstock, shipping, power. Either way there’s a lot of green industrial H2.
@BashStKid @mackaj @SkipHuffman @Porcia ultimately it's easier to run a cable than you transport hydrogen.
@quixoticgeek @mackaj @SkipHuffman @Porcia
I agree, especially if someone would hurry up and discover an LK-99 rt superconductor that actually works.
But there are always some use cases where it makes sense.
@BashStKid @mackaj @SkipHuffman @Porcia yes. but it's gonna be for hydrogen as a feed stock, not hydrogen as an energy source. You might get an electrolysis plant situated next to the ammonia plant... Or next to the steel plant... I don't think we're gonna see a lot of hydrogen being shipped from say, north Africa, to Europe to power stuff. You can run a 1000km HVDC cable with much fewer loses instead. More likely an ammonia plant next to solar farm in north Africa...
@BashStKid @quixoticgeek @mackaj @SkipHuffman @Porcia HVDC, while not actually superconducting, is close. And useable underground/underwater.
@martinvermeer @BashStKid @mackaj @SkipHuffman @Porcia yeah. It's looking at about 3% loss on a 1GW cable over 1000km. That's impressively efficient. I'm expecting to see a lot more of them from renewable rich locations in the coming years.
@quixoticgeek @martinvermeer @mackaj @SkipHuffman @Porcia
Can’t come too soon. I think we’re already so far behind with grid upgrades in the UK it might be cheaper and quicker to build an offshore distribution network. Also there’s the Xlinks Morocco-UK project.
Any others you folks know of?
@BashStKid @quixoticgeek @mackaj @SkipHuffman @Porcia Just recently:
Prysmian, the makers of the cable, are located at a place in South Finland that I drive by most every week...
@BashStKid @martinvermeer @mackaj @SkipHuffman @Porcia Norway to NL is already up. Norway to UK likewise. Denmark to UK as you mentioned is online as of this week. There's talk of Iceland to UK. And there's talk of Morocco to UK as a 3Gw HVDC cable...
@quixoticgeek @SkipHuffman @mackaj @Porcia
Yes, the local LP distribution network. I was thinking the key bottleneck would be in the HP transmission system.
Same applies though, the combination of energy density/mass and gas compressibility means hydrogen has to be at 5-6 times methane pressure to deliver the same energy volume throughput. Few lines could safely take 6 x design operating pressure.
(Unless I messed up some numbers …)