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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

#381

Earlier quoted context omitted.

It is not "tone policing". That is an accusation guaranteed to derail any discussion. Nukes and geothermal simply cost more than solar and wind: nukes, many, many times more. Spending a billion dollars gets you N GW of solar or wind, and N/M, M>>1, of others. Generally, if you need a steam turbine to keep working, you will trail behind anything with zero opex. Hydrogen has a plausible place in long-term (i.e. strateg…

It ain't the money cost, we have money coming out our ears. It's the time cost. Nuclear takes far too long; geothermal merely takes too long. Same with fancy long-distance HV transmission proposals. Can it be built and commissioned in a year? Do it.

Point. We are in a race against global civilization collapse.

But the race is, at base, to displace atmospheric carbon release. So displacing more, faster is the measure of merit.

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

#382

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…

>It feels like the "save the planet" movement, or at least some shards of it, come with a very specific notion of how exactly it is ok to save the planet Yes, it does. It a very thinly veiled anti human movement. Ultimately, there is a loud sub section of environmentalists whose only acceptable solution will be "less humans" and they dupe a number of their fellow travellers with endless "but what about X" problems so…

Not sure I understand your thinking here. Are you saying that the current number of humans is exactly the right amount? Or are you saying that we should maximize the number of humans on the planet?

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

#383
post #23

Earlier quoted context omitted.

Hydrogen is a battery with very particular uses cases. In particular: hydrogen is bad for use cases with large numbers of charge/discharge cycles, because the "cost of inefficiency" is proportional to the number of such cycles. However, for use cases with small numbers of charge cycles, like seasonal storage or backup against rare grid outages, hydrogen's big advantage -- the low cost of storing it, vs. typical short…

>hydrogen's big advantage -- the low cost of storing it Hydrogen by its very nature, due to it being the smallest atom, embeds itself into the walls of its container. It will rot the metal walls you use to hold it long term. Look up "hydrogen embrittlement"

It's stored underground in caverns, not in metal pressure vessels. This is a demonstrated technology. It's also the same way natural gas is stored. The cheapest option is solution mined cavities in salt formations. Europe (for example) has enough salt formations to store many petawatt hours of hydrogen.

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

#384

Earlier quoted context omitted.

Green hydrogen is made from electricity. The cost of green hydrogen is currently high, but it is dropping faster than pretty much any other energy storage technology. Hydrogen storage is an order of magnitude cheaper (or more) than any other tech. It is expensive because of the cost of electrolyzers/fuel-cells that convert between electricity and H2. These costs are dropping fast at efficiencies of 80%+ along with th…

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.

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

#385
post #76

Earlier quoted context omitted.

> They're a car company committed to keeping the internal combustion engine. A vehicle running on hydrogen isn't an ICE. These are fuel cells. https://en.wikipedia.org/wiki/Toyota_Mirai This is an electric vehicle which generates power through hydrogen fuel cells rather than storing it as electrical energy in a battery (though it has a battery too). > Toyota's latest generation hybrid components were used extensively…

On a technical note, it's still an ICE. And Toyota's absolutely trying to show that it can actually be pretty much the same ICE but reinforced to deal with the much higher pressures from having to work with compressed hydrogen. But, while there is still internal combustion happening the major difference is that a hydrogen ICE produces heat and mostly water, rather than heat and mostly CO2 ( ). You just can't go as fa…

For Toyota Mirai - the https://www.toyota.com/mirai/

Is it an internal combustion engine? https://youtu.be/qWMqZgiFhQY

This isn't a one off "hey we can do it" as a proof of concept for a race but an actual production car that you can buy.

> You just can't go as far on hydrogen mostly because the amount of dead weight required for hydrogen is so much higher than for fossil or electric.

To which https://www.toyota.com/mirai/2023/mirai-features/performance...

> Up to 402-Mile Range

> When fully fueled with hydrogen, the 2023 Mirai XLE has an impressive manufacturer-estimated 402-mile driving range rating * and the 2023 Mirai Limited has a 357-mile driving range rating.

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

#386

Earlier quoted context omitted.

> It feels like the "save the planet" movement, or at least some shards of it, come with a very specific notion of how exactly it is ok to save the planet, and what fails on style points. This has always been a pain point for me. If you feel the world is facing an existential crisis (and I do), then it seems weird to go down the list of possible ways of avoiding utter catastrophe like you're at a sushi bar: Solar: Ah…

It is not "tone policing". That is an accusation guaranteed to derail any discussion. Nukes and geothermal simply cost more than solar and wind: nukes, many, many times more. Spending a billion dollars gets you N GW of solar or wind, and N/M, M>>1, of others. Generally, if you need a steam turbine to keep working, you will trail behind anything with zero opex. Hydrogen has a plausible place in long-term (i.e. strateg…

They are more expensive only when compared to a marginal kWh put at time of solar/wind’s convenience into the grid that is stabilised by other means (mostly fossils). Look up how much electricity went up in Texas last time the generation dropped by iirc just ~20%; solar goes to zero every night, and wind regularly dies down across Western Europe for days or even weeks. In those circumstances and without fossils to fall back to, nuclear is infinitely cheaper than solar/wind.

We can’t plan our grids or judge the costs according to not just best, but even average scenarios. We have to plan once-in-decades anomalies, the long tail. Non-dispatchable energy sources get exponentially more expensive once you start doing that.

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

#387

Hydrogen is a storage technology. When I looked at it last, it was largely planned to be produced by electrolysis, so the greenness of that depends on the power source for that operation. So it could be green if powered by solar? Or brown, if powered by coal.

Hydrogen can also be "reformed" from other fuels, most particularly natural gas, or through carbon capture and storage (CCS).

There are trade terms that have emerged, including "black", "brown", "grey", "blue", and "green" hydrogen which ... aren't especially clear or consistent in my experience.

WEF have a 'splainer, though I'm not sure the classifications are universally accepted:

https://www.weforum.org/agenda/2021/07/clean-energy-green-hy...>

Apparently NG -> H2 is "grey" or "torquiose", and CCS is "blue".

"Green" is hydrolysis from renewable electricity.

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

#388

Earlier quoted context omitted.

I’m curious how the calculations work here. I know that any individual battery electric car is better in terms of GHG emissions than any individual hybrid car. However, given the limited number of battery electric cars, and the limited production, battery electric cars will remain the minority of all cars at least until the end of this decade (probably even longer). Now my question is, en masse, since the production…

I can't find it right now, but a toyota engineer has actually discussed this. Toyota looks at it this way, especially since you are wasting significant battery capacity on BEV's that don't get utilized daily if the battery supports significantly longer range than daily commute.

I often wonder, since we are in a climate emergency, and we are still increasing our GHG emissions, and we need to electrify so much as quickly as possible. And we have these lithium ion batteries which work pretty well for that, but the production capabilities are limited, so you would think we would put them where we’d get the most use our of them, but alas, most we get is a bunch of Tesla SUVs and maybe a Hummer EV.

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

#389

Earlier quoted context omitted.

It is not "tone policing". That is an accusation guaranteed to derail any discussion. Nukes and geothermal simply cost more than solar and wind: nukes, many, many times more. Spending a billion dollars gets you N GW of solar or wind, and N/M, M>>1, of others. Generally, if you need a steam turbine to keep working, you will trail behind anything with zero opex. Hydrogen has a plausible place in long-term (i.e. strateg…

They are more expensive only when compared to a marginal kWh put at time of solar/wind’s convenience into the grid that is stabilised by other means (mostly fossils). Look up how much electricity went up in Texas last time the generation dropped by iirc just ~20%; solar goes to zero every night, and wind regularly dies down across Western Europe for days or even weeks. In those circumstances and without fossils to fa…

The "stable grid" argument is well past its sell-by date.

In the future we will need to build out storage. Before there is enough renewable generation to charge storage, building it would be foolish. After, we will need storage, and build it.

And, we will always need liquid fuel. As cost for renewables continues exponentially downward, ammonia synthesized at solar farms in the tropics will undercut NG. In the meantime, shortfalls will be filled by burning an ever-decreasing amount of NG.

We will need a hell of a lot of electric ammonia synthesis in coming decades.

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

#390

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…

ICE vehicles conquered the world with abysmal efficiencies, they were around 10-15% when they already ruled the roads and the world. That is after we drill for oil, ship it, refine it, distribute it. Even today, manufacturers boast about engines with 40% efficiency in ideal conditions, which still translates to a meager 20-30% in real world driving. Looking at efficiency alone is not enough. > They're simply so much…

>ICE vehicles conquered the world with abysmal efficiencies, they were around 10-15% when they already ruled the roads and the world.

Fossil fuel comes out of the ground with the energy already in it, hydrogen doesn't exist in a free form and the energy must be put into it coming from somewhere else.

Most hydrogen now comes from natural gas at maybe 75-80% efficiency through reforming, then it must be compressed, then it must be burned at similar efficiencies to fossil fuel or used in a fuel cell with slightly better efficiency than ICE.

It's way worse in efficiency than fossil fuels, you could just use the natural gas directly in a combustion engine and be way ahead. Solar/wind/nuclear to electrolysis is even worse, just charge a battery.

Hydrogen is a energy storage mechanism like a battery not a source of energy like fossil fuel.

Look at well to wheel efficiency BEV are far ahead of hydrogen.

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