Methane is needed to make hydrogen, which you can easily make from electricity and water. It’s just cheaper to make from methane so there aren’t facilities to make it using green energy.
Would methane be an easier fuel to work with than hydrogen? Which is cheaper to produce from electricity? The wikipedia article[1] says methane could be produced from Hydrogen, but I believe there is a process to produce methane from water and CO2 directly.
Hydrogen is a feed stock for green steel production, which isn't commercially developed yet.
Methane is a better fuel for that than hydrogen, you can make it from air plus energy (although not easily - there's not enough CO2 in the air for that). Or, more practically, coal and water and energy.
You're complaining about the low efficiency of H2, and then you end up proposing methane as an alternative?
To create methane from electricity you need hydrogen to begin with. To create methane from that you need CO2, which you can get from the air and needs a lot of energy (alternatively you can get it from other emisssion sources, but well, we want to get rid of them, so this is at best an intermediate solution). You end up with much less efficiency compared to hydrogen.
Methane has only one thing going for it, and that is existing infrastructure and processes. But that's a mode of thinking where you try to think how you can keep the technology from a fossil energy system.
I share some skepticism about hydrogen. It probably shouldn't be applied where more efficient technologies are available. But there's a whole lot of areas where hydrogen really is the only game in town right now. And in many other areas it's an intermediate product needed for further steps.
the efficency of the process probably prevents market adoption
I think this is correct right now, but the biggest cost by far for generating green methane at scale would be the energy costs for electrolysis to get the hydrogen from water. If renewables continue to fall in cost, we may rapidly reach a point where we have a huge surplus of green energy for parts of the year. There are already places in the US where energy prices regularly go negative due to excess wind energy, for example.
Folks have talked a lot in the past about using excess energy from renewables to generate hydrogen gas, but hydrogen alone is a lot harder to manage, is much less energy-dense by volume, is impractical to liquefy for storage and transport, and isn't compatible with existing infrastructure. Methane solves all of these issues, and doesn't take much additional energy to create beyond what you must spend for hydrogen alone.
An alternative solution to hydrogen could be methane synthesis from captured CO2 and green hydrogen. The infrastructure to transport, store and use methane (aka 'natural gas') is already there.
Hydrogen is needed for all kinds of industrial processes, but it is best generated at the point of use as needed, as storage and transport is too problematic. If absoultely needed, the most obvious way to ship hydrogen is as methane.
Synthesis of methane from water-sourced hydrogen and atmosphere-sourced CO2 is at present a good deal more expensive than fossil natural gas, but that's a somewhat artificial situation: natural gas production is heavily subsidized and many of the costs are externalized to the public (see global warming, air and water pollution, etc.). However, once accomplished you can just feed this renewable methane into the existing natural gas infrastructure, and get the hydrogen back as needed from well-understood processes, i.e. steam-methane reforming.
It's only far away if you want to work in pure hydrogen, which is ideologically simple but not really required. Synthesis of methane from hydrogen is easy and efficient and (pretty) cheap - use atmospheric co2 as carbon feedstock. A German company is working on this and has proven solution at small scale, I'm sure they're not the only ones.
More of a pain than simply burning/recombining hydrogen with oxygen, but has the upside that there is already a huge and established global network for transport and storage of methane - cheap and proven and currently being rapidly scaled.
Sure. But we also can synthesize methane from captured carbon dioxide and green hydrogen. It's still more expensive than fossil methane, but it's getting cheaper.
But we can start transitioning factories to use methane right now, starting from fossil methane and slowly moving to greener sources.
I would assume that it's just simpler to synthesize methane (power-to-gas) and use that to (e.g.) fuel vehicles. Assuming you're pulling H from water and CO2 from the air, the methane is carbon neutral, so there's no huge reason to try to transport hydrogen.
I think it would be much easier to use methane. Just as carbon neutral if you make it yourself, and doesn't have as many exotic engineering requirements.
I didn't know that about fuel cells though, interesting.
Synthesizing h2 from methane is also done by electrolysis, it's just cheaper to electrolyze methane than water. This is fundamental - it takes less energy to release hydrogen from methane than from water, to such a degree that even though water is free it's still not economical. If you are concerned about people using fossil instead of synthetic methane to cut costs, you should be concerned about people using methane instead of water to cut costs. Either you can get people to comply with regulations or you can't.
Hydrogen is cool, but we should also be investing in efficient methane production. AFAICT it's not too hard to make and has immense advantages - existing transport, storage and use infrastructure and market as a heavily traded good. We can use it for most of our energy or carbon needs with today's technology and existing machines with no or easy modifications.
Hydrogen can be more efficient and probably simpler when appropriate but is more finicky, still needs research and will take a lot of time to ramp up.
You generate hydrogen using excess renewables, then turn that into methane and store it to burn in conventional gas power plants. Look up various versions of Power2Gas. It's not economical right now because we have few times when renewable production exceeds demand but is a natural component of a fully renewable power grid.
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