this post was submitted on 11 Mar 2026
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Climate

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Discussion of climate, how it is changing, activism around that, the politics, and the energy systems change we need in order to stabilize things.

As a starting point, the burning of fossil fuels, and to a lesser extent deforestation and release of methane are responsible for the warming in recent decades: Graph of temperature as observed with significant warming, and simulated without added greenhouse gases and other anthropogentic changes, which shows no significant warming

How much each change to the atmosphere has warmed the world: IPCC AR6 Figure 2 - Thee bar charts: first chart: how much each gas has warmed the world.  About 1C of total warming.  Second chart:  about 1.5C of total warming from well-mixed greenhouse gases, offset by 0.4C of cooling from aerosols and negligible influence from changes to solar output, volcanoes, and internal variability.  Third chart: about 1.25C of warming from CO2, 0.5C from methane, and a bunch more in small quantities from other gases.  About 0.5C of cooling with large error bars from SO2.

Recommended actions to cut greenhouse gas emissions in the near future:

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[–] gandalf_der_12te@discuss.tchncs.de 0 points 11 hours ago* (last edited 10 hours ago) (3 children)

You can generate hydrogen from electrolysis.

Electrolysis efficiency is about 70% and you can store the hydrogen in pressurized underground caverns for a year or longer using another 0.12 kWh per kWh of hydrogen stored, which makes a total efficiency of around 0.6 kWh of hydrogen generation and storage for every kWh of electricity that you put in. (Source)

So if your electricity costs 6 ct/kWh (current LCOE of solar in many places), then hydrogen is gonna cost 10 ct/kWh to generate and store with current technology.

Currently, natural gas is around 5 ct/kWh, so solar would have to become a little bit cheaper to make it economically competitive.

Edit: to clarify, the 5 ct/kWh for natural gas is the gas alone; electricity from natural gas is more expensive than that (around 12 ct/kWh) and more expensive than solar.

[–] how_we_burned@lemmy.zip 1 points 6 hours ago

What are you going to store hydrogen in to make this remotely viable? You lose like 60% of hydrogen within 7 days with current tanks and seals.

The new sodium batteries make this completely pointless from a cost and efficiency context

[–] rapchee@lemmy.world 1 points 10 hours ago (3 children)

is home hydrogen a thing? i was wondering before, if it works in cars, why is it not in houses?

[–] Duamerthrax@lemmy.world 1 points 9 hours ago

There's a engineer that did it in his backyard. I'll see if I can find it when I get home.

[–] Cethin@lemmy.zip 1 points 9 hours ago

Technically it could work. However, traditional batteries make a lot more sense. Hydrogen makes some sense for a vehicle because it can be more energy dense (it actually only makes sense for large trucks). However, it has to be stored at cryogenic temperatures. In a place where you probably don't care about mass or space much, other battery technologies are far better, without the added cost of cryogenic cooling and having to deal with hydrogen, which leaks through anything.

hydrogen scales well if you use big industrial setups, both for generation and for storage.

basically, bigger tanks are cheaper (consider higher volume/surface area ratio) and in fact the best tanks might simply be naturally occurring underground caverns. you can't have these at home.

[–] boonhet@sopuli.xyz 1 points 10 hours ago (1 children)

That sounds cheaper than battery storage (which at latitudes bigger than yours can get very expensive since there's little to no sun in the winter), and I'd assume more environmentally friendly than mining all that lithium as well.

How expensive is it to build out said caverns for this use, particularly if there aren't many natural ones available?

[–] gandalf_der_12te@discuss.tchncs.de 1 points 10 hours ago (2 children)

basically the caverns that are being considered/used for this are the same caverns that natural gas was extracted out of in the first place ... they clearly held some sort of gas fine for millions of years, so certainly they're gonna store a bit of hydrogen too.

[–] Passerby6497@lemmy.world 1 points 7 hours ago

they clearly held some sort of gas fine for millions of years, so certainly they’re gonna store a bit of hydrogen too.

Not to rain on your parade, but hydrogen and natural gas aren't really comparable for storage. The natgas molecule is 8x heavier and MUCH larger than a molecule of hydrogen. Just on the size alone, hydrogen can slip through just about everything and needs to be stored at cryogenic temperatures. I don't think rock is going to be as good of a storage media as you'd assume.

[–] boonhet@sopuli.xyz 1 points 9 hours ago (1 children)

Oh that makes sense.

We just don't have any natural gas production in Estonia lol. Perhaps the shale mines could be used. Unfortunately the biggest one had its permit extended till 2049 recently. Also I think they get filled with water naturally (they pump out a lot of dirty water), so I suppose the walls aren't actually completely sealed naturally.

yeah, geological availability might vary