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Japan's hydrogen strategy does nothing for decarbonisation: study

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Re: Japan's hydrogen strategy does nothing for decarbonisation: study

#421
post #384

Earlier quoted context omitted.

Japan plans to make hydrogen using high-temperature nuclear reactors (HTGR or HTTR). See: https://www.jaea.go.jp/04/o-arai/en/research/research_03.htm...

Nifty. The chemical process involved appears to be: https://en.m.wikipedia.org/wiki/Sulfur–iodine_cycle 50% thermal efficiency from nuclear to hydrogen sounds very good.

Except nuclear steam generators have to run at well under 830 degrees and at low head because of two loop cooling and corrosion issues so odds are pretty good this will be about as reliable as every other gas cooled reactor and be shut down in 10 years.

Re: Japan's hydrogen strategy does nothing for decarbonisation: study

#422

Earlier quoted context omitted.

> Throwing energy away is counterproductive, and Energy-to-Hydrogen-to-Energy throws away lots of it. Energy to plants to biofuels throws away nearly all the energy. More than all of it, by some accountings. What are the alternatives for those use cases in which batteries are infeasible?

You'll never hear me defend biofuels. The alternatives are mostly * better batteries * heat pumps to replace oil burners * methane or ammonia for the remaining uses (eg trans-oceanic); globally shipping and aviation together account for only 8% of petroleum use With a universal carbon tax everything would automatically self-organize into the most efficient solution, but of course we can't do that.

Off-road land use probably accounts for another few percent. It's hard to imagine heavy forestry, farming, and earthmoving equipment being powered by batteries.

Re: Japan's hydrogen strategy does nothing for decarbonisation: study

#423

I find it weird how hostile to hydrogen the "renewable energy gang" is. The story of how renewables take over the world and displace fossil fuels and nuclear totally relies on storage, in some cases seasonal storage, IE overproducing in summer and holding on to the energy til the end of winter. Does hydrogen work for it? Well, maybe, it could, there are unresolved issues but hey we are trying to do science here. It's…

I am not sure if you are pretending to be oblivious or not but it isn't "weird" at all. Batteries make Elon money. Hydrogen fueled machines do not. If you are online in an English speaking forum expect the majority to support Elon, pied piper de jour.

Re: Japan's hydrogen strategy does nothing for decarbonisation: study

#424

Earlier quoted context omitted.

You'll never hear me defend biofuels. The alternatives are mostly * better batteries * heat pumps to replace oil burners * methane or ammonia for the remaining uses (eg trans-oceanic); globally shipping and aviation together account for only 8% of petroleum use With a universal carbon tax everything would automatically self-organize into the most efficient solution, but of course we can't do that.

Off-road land use probably accounts for another few percent. It's hard to imagine heavy forestry, farming, and earthmoving equipment being powered by batteries.

Why not?

It seems like the real problem is a lack of imagination.

Are there some challenges? Of course. Are they insoluble? I can't see why they would be.

Re: Japan's hydrogen strategy does nothing for decarbonisation: study

#425

Earlier quoted context omitted.

The problem isn't "dogma," it's inefficiency. Throwing energy away is counterproductive, and Energy-to-Hydrogen-to-Energy throws away lots of it. If there were no alternative long-term storage plans this might be acceptable, but that's simply not the case. If you're using hydrogen to smelt steel or make ammonia fertilizer, then there's no energy loss (beyond what's needed to decarbonize petrochemicals anyway). The ar…

Isn't the whole point of cheap and plentiful renewable energy that inefficiencies in processes like this are irrelevant? Why would long-term storage matter if wind and solar can produce so much energy that we cannot feasibly consume it all? What other long-term energy storage plans are there right now? I would not write off fuel stations just yet. There may well be a future where some renewable fuel powers vehicles.

>Isn't the whole point of cheap and plentiful renewable energy that inefficiencies in processes like this are irrelevant?

No.

You're thinking of "too cheap to meter," which never came to pass, and (as it turns out) was just a marketing line.

>What other long-term energy storage plans are there right now?

https://news.ycombinator.com/item?id=34429623

There was a great article a few days ago about "factories as batteries" (pointing out that aluminum smelting is uneconomic but hydrogen works) but sadly I can't find it.

Re: Japan's hydrogen strategy does nothing for decarbonisation: study

#426

Earlier quoted context omitted.

I thought the article was fairly to the point: > There is a “common understanding worldwide that hydrogen should be limited to applications where it would be difficult to achieve decarbonisation with other methods”, says the report by the Tokyo-based non-profit think-tank Renewable Energy Institute (REI), but Japan has instead laid out a vision of a “hydrogen society where hydrogen is used in every sector”, while pro…

I find there is a selective black and white perception of the world. For example, renewables right now rely heavily on quick-to-dispatch gas plants - and that's fine as a stepping stone to a carbon-free future. Though the plan fo eliminating it is still vapourware - maybe better batteries, maybe larger grids, maybe something else. But creating a hydrogen economy that somewhat relies on fossil fuels, with a clear path…

It's not about purity, it's about removing carbon from the atmosphere. All the existing industrial scale hydrogen production gets hydrogen from carbon based fuels, using other energy. There doesn't appear to be an option at this time for producing carbon at any reasonable scale without using carbon fuel sources. If we get fusion power, really cheap power, instead of splitting water using that free energy we could just directly run electric cars. There is a cynical pushing of "green hydrogen" from the companies that want to preserve their internal combustion industrial infrastructure (notably Japan), and from carbon fuel producers but calling the result 'green hydrogen'. The issue is there is no clear pathway. When/if that happens, there's still the issue of the infrastructure to manage carrying around hydro to refuel or making it at the source. There's no there there.

Re: Japan's hydrogen strategy does nothing for decarbonisation: study

#427

Earlier quoted context omitted.

Did you read past the headline? It's not anathema because of aesthetics, it's anathema because it doesn't work. There's nothing wrong with shooting down an idea that you have studied and found to be counterproductive.

It doesn't say anything like it, and your comment doesn't address mine either. 1. That particular approaches don't work is irrelevant. TFA focuses on a particular Japanese policy, which may or may not be misguided. The article is light on discussion, but let's take it at face value. Should we say wind+solar is stupid because Germany is currently in an energy mess? I don't think so. 2. I don't think it's dumb at all t…

There's one key problem, making hydrogen without creating more carbon in the atmosphere. If they solve that, then it's worth considering. If we have fusion providing endless electric energy (which could be used to split water), then we could just use it to fuel electric cars too. There's the classic problems of lack of energy density, and hydrogen fires not being visible. I think we can probably make hydrogen containment systems better, and figure out how to make fires visible. To me it all comes back to getting the fuel. When we can do that we can consider it.

Re: Japan's hydrogen strategy does nothing for decarbonisation: study

#428
post #427

Earlier quoted context omitted.

It doesn't say anything like it, and your comment doesn't address mine either. 1. That particular approaches don't work is irrelevant. TFA focuses on a particular Japanese policy, which may or may not be misguided. The article is light on discussion, but let's take it at face value. Should we say wind+solar is stupid because Germany is currently in an energy mess? I don't think so. 2. I don't think it's dumb at all t…

There's one key problem, making hydrogen without creating more carbon in the atmosphere. If they solve that, then it's worth considering. If we have fusion providing endless electric energy (which could be used to split water), then we could just use it to fuel electric cars too. There's the classic problems of lack of energy density, and hydrogen fires not being visible. I think we can probably make hydrogen contain…

https://www.powermag.com/fukushima-hydrogen-energy-research-...

> For the past two years, FH2R has consistently been ranked as one of the world’s largest projects of its kind. According to project participants, FH2R uses a 20-MW solar PV array built on a 180,000-square-meter site along with grid electricity to power a single-stack 10-MW-class electrolyzer. Its developers say it can produce, store, and supply up to 1,200 Nm 3 /hr of hydrogen at rated power operation.

This is a "its not completely there yet but this is where its trying to go."

Re: Japan's hydrogen strategy does nothing for decarbonisation: study

#429
post #165

Earlier quoted context omitted.

And the rest of the world? And when extra energy is needed because of a cold/heat-wave, new project, or just an event in a forest? These scenarios, both large and small, are covered currently by fossil fuels, and are not answered by permanent grid solutions like HVDC. The generation price of solar energy is ~$0.02/kwh. Even with 33% overall efficiency hydrogen could be very competitive at $0.06/kwh electricity. , But…

> The generation price of solar energy is ~$0.02/kwh. Even with 33% overall efficiency hydrogen could be very competitive at $0.06/kwh electricity. , But overall efficiency is a red-herring. The important thing is COST. With solar, the cost of energy itself is the smallest part - providing it at the desired time and place are the more expensive parts. I'm not sure what you're saying here. Hydrogen produced with green…

It's very simple - there is a need for a dispatchable and transferrable form of energy. So far, this need has been fulfilled by fossil fuels, and if arguments against P2G solutions prevail, will probably continue for a long time.

But at least we will be physically efficient.

Re: Japan's hydrogen strategy does nothing for decarbonisation: study

#430
post #101
post #43

Earlier quoted context omitted.

Rare prolonged outages are bad for batteries, since the capital cost is too high. You want something that has very low capital cost, even if it burns a fuel. Simple cycle gas turbines power plants might cost $0.50/W.

> Rare prolonged outages are bad for batteries, since the capital cost is too high. You could subsidies that by using your batteries to energy to peak load times?

Batteries sufficient for short term leveling would run out too quickly. If you build enough batteries for prolonged outages most of them would be unused during the leveling of short term fluctuations.
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