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MatthewToad43

matthewtoad43@climatejustice.social
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Former and hopefully future climate and poverty activist. Covid cautious. Autistic grey-ace/wtf-ro geek, software developer. Interested in green transition, green tech, activism, intersectionality, etc. I try to boost other marginalised voices while recognising my own privilege. Yorkshire, Remainer. Climate hawk on the pro-tech end: We need *appropriate* technology. Recently re-created this account after leaving for a while during an anxious period of unemployment.

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@flux @QuinceDaPence Concrete and steel (for stations, track, etc) matter. So does the electricity used to maintain stations, not just propel the train. So lifecycle emissions of a train are immensely complicated, plus then you get into how to route a new rail line without destroying too many ecosystems.

Even so, clean electricity is the easy bit compared to making planes clean. More trains please.

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@flux @QuinceDaPence The other common gotcha with new train lines (e.g. HS2) is:

What if we get a modal shift from internal flights to trains? If air demand is constrained by supply (i.e. landing slots), that means there will be more long-haul flights, and overall emissions increase!

There is some truth in this. But it just means we need to drastically reduce our aviation capacity, and increase prices, at the same time as building more train lines. We could start with a frequent flyer levy.

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@MattMastodon @BrianSmith950 @Ardubal @Pampa @AlexisFR @Wirrvogel @Sodis There seems to be a lot of uncertainty around the cost of green hydrogen. The first three Google links differ wildly on it.

Natural gas has certainly increased the cost of grey hydrogen lately.

If the problem is the cost of electricity, that’s easily solved by producing mainly when there’s a surplus of green electricity. However, if the cost is the capital outlay, that’s harder. Which is it?

Of course, we can and must require by law that all new capacity be green. Current incentives also include blue, but there is more green hydrogen actually being built.

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@MattMastodon @BrianSmith950 @Ardubal @Pampa @AlexisFR @Wirrvogel @Sodis IIRC most studies show that long term storage is only a few percent of total energy, certainly well under 10%. So it is a viable option - if you can get past leaks, and other problems (e.g. the temptation to burn it, producing NOx pollution). And can store vast amounts of energy relatively cheaply.

Nuclear is of course a viable option. There are a few others e.g. iron-air batteries, or just building a lot more renewables than we need. Long range interconnectors help. Lithium is only helpful for short to medium term storage.

Re synthetic fuels, so far extremely expensive and limited scale. Might possibly be used for aviation in the long run (but it’s easier just to fly less, and we still need a reliable, safe solution to the contrails problem). Maybe shipping too (possibly as ammonia).

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@MattMastodon @BrianSmith950 @Ardubal @Pampa @AlexisFR @Wirrvogel @Sodis Here’s a study from a while back about how much storage is actually needed, using the example of Australia. You can get to ~98% with relatively little storage. For the remaining 2%, you need to think about more difficult options - demand side measures, nuclear, long term storage, etc.

https://reneweconomy.com.au/a-near-100-per-cent-renewables-grid-is-well-within-reach-and-with-little-storage/

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@MattMastodon @BrianSmith950 @Ardubal @Pampa @AlexisFR @Wirrvogel @Sodis There is commercial production of green hydrogen today, but it requires a subsidy. The cost of grey hydrogen does not reflect the damage it causes.

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@MattMastodon @BrianSmith950 @Ardubal @Pampa @AlexisFR @Wirrvogel @Sodis Well, California has done a lot of the work for you. Have a look at their charts, including multiple GW of battery storage.

Also the study I posted about Australia. There was another one but I lost it on the other place. You can get *most* of the way with a few *hours* storage, not weeks.

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@MattMastodon @BrianSmith950 @Ardubal @Pampa @AlexisFR @Wirrvogel @Sodis What that means is if you’re going the long term storage / hydrogen or iron-air batteries route, the inefficiency doesn’t matter (but the capital cost does).

On the other hand if you try to reach 100% with minimal demand side interventions even in emergencies, you end up building way more (~3x) renewables than you ideally need. Which has a cost - rare earths etc.

But there are plenty of options for managing intermittency. All of them have problems or costs though. Which is one reason I’m not strongly opposed to nuclear, for instance, but nor am I terribly enthusiastic about its ability to deliver quickly enough.

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@MattMastodon @BrianSmith950 @Ardubal @Pampa @AlexisFR @Wirrvogel @Sodis Also, which country is that? Look at e.g. today’s UK chart - wind was dominant until 6:30PM. Sadly this service does not include batteries because there’s no data on *charging* them.

https://grid.iamkate.com/

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