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Israeli Researchers Produce Green Hydrogen with 90% Efficiency

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Re: Israeli Researchers Produce Green Hydrogen with 90% Efficiency

#21

Post by mustafa_pasi »

bkor wrote: post #19
mustafa_pasi wrote: post #14

Earlier quoted context omitted.

The obsession with efficiency is disingenuous too. The two limiting factors are generation capacity and cost/economics. Efficiency by itself says nothing. In the early 1900s, gas was less efficient than electricity too, but for a whole century gasoline powered transportation was more feasible. Aviation is still only feasible with kerosene despite it being less efficient than electric propulsion.

Efficiency has a huge impact on the cost/economics, something that you've highlighted. If significant more energy is needed, it'll likely be more expensive. Hydrogen is sometimes only a third as efficient as other solutions. It's pretty logical to assume it'll be > In the early 1900s, gas was less efficient than electricity too I think you mean gasoline instead of just gas. Hydrogen requires huge amounts of energy be…

>Efficiency has a huge impact on the cost/economics

Not in the way that you think, no. For all intents and purposes, we have limitless energy. The problem was never that we don't have enough capacity, because we can scale capacity as much as we want. The only thing that is required is that energy generation (i.e. $/kWh) is cheap enough, and this seems feasible with solar and wind and maybe fission and later one fusion or other sources.

>you're comparing apples to oranges

You are the one saying, "just attach a transmission line to it" or "just put a battery in it", without thinking of all the cases where this is just not possible.

Nobody is arguing that you should start powering your toaster with hydrogen. You all are attacking a strawman, it seems.

Re: Israeli Researchers Produce Green Hydrogen with 90% Efficiency

#22

Post by arijun »

aredox wrote: post #18
_aavaa_ wrote: post #12

> When it is genuinely green, it is obtained through electrolysis, a process that is only 70% to 80% efficient. That's not bad compared to internal combustion engines (ICEs), but fuel cell detractors use that to bash them anyway. Scientists at Tel Aviv University plan to kill that argument with a method that is over 90% efficient in generating green hydrogen. This is highly disingenuous. The problem isn't just that e…

I concur: Hydrogen is a "bad" fuel in terms of practicality: it's extremely reactive and it leaks easily. To make a parallel with rocket science: there are extremely efficient liquid chemical propellants, much better than what is in use today, like Chlorine Trifluoride, that nobody uses anymore because they are just too dangerous to work with. Or the fact that hydrogen airships will never come back: nobody will ever,…

I was curious about Chlorine Trifluoride as a propellant, and I found this quote of John D Clark on the Wiki page (hypergolic means it will ignite spontaneously):

> It is, of course, extremely toxic, but that's the least of the problem. It is hypergolic with every known fuel, and so rapidly hypergolic that no ignition delay has ever been measured. It is also hypergolic with such things as cloth, wood, and test engineers, not to mention asbestos, sand, and water—with which it reacts explosively. It can be kept in some of the ordinary structural metals—steel, copper, aluminum, etc.—because of the formation of a thin film of insoluble metal fluoride that protects the bulk of the metal, just as the invisible coat of oxide on aluminum keeps it from burning up in the atmosphere. If, however, this coat is melted or scrubbed off, and has no chance to reform, the operator is confronted with the problem of coping with a metal-fluorine fire. For dealing with this situation, I have always recommended a good pair of running shoes

Re: Israeli Researchers Produce Green Hydrogen with 90% Efficiency

#23

Post by greenthrow »

taylodl wrote: post #13

"Hydrogen storage would still be a problem unless the gas was transformed into synthetic fuel. Hopefully, another scientific breakthrough could address that as soon as possible. We also have another idea floating around that may help solve that." This statement at the end of the article leads me to believe any widespread distribution of hydrogen is at least 10 years off. It'll be interesting to see if Toyota is vindi…

Nope. It doesn't make sense for long range trucks either. Hydrogen trucks do not have more range than BEV trucks, and they are significantly more expensive to fuel. Battery energy density is increasing and cost is decreasing so fast that hydrogen is irrelevant for all ground transport. In 10 years we will laugh that anyone thought hydrogen was the future.

Re: Israeli Researchers Produce Green Hydrogen with 90% Efficiency

#24

Post by ComputerGuru »

ben_w wrote: post #4

Interesting; I wonder if similar approaches will help make the fuel cells cheaper as well as hydrogen? Even if not, even if vehicles remain fully electric (which is my assumption): > The scientists said gray, black, and brown hydrogen release 9 to 12 tons of carbon dioxide for each ton of hydrogen produced. Yet, they correspond to 95% of all hydrogen currently produced worldwide for agricultural and industrial needs.…

> On a separate topic: this is the second site in a row where the full-screen "we respect your privacy click here to agree" banner won't actually let me scroll down to any of the buttons.

https://chrome.google.com/webstore/detail/behind-the-overlay...

Re: Israeli Researchers Produce Green Hydrogen with 90% Efficiency

#25

Post by PaulKeeble »

Even if hydrogen could be created with 100% efficiency it would still be very poor compared to just using electricity from batteries. The issue is the engines themselves are very inefficient, something like 20-30% and as such the same electricity will go a lot further directly compared to burning hydrogen. There are so many extra inefficiencies with transport and storage compared to existing and improved electrical infrastructure, its just not competitive.

It might have some benefits in certain vehicle types where energy density and being far from a grid might make it beneficial but it will be a lot more expensive than electrical vehicles. Portable charging infrastructure with and wind and solar will often be a better option.

I can't see hydrogen being anything but niche now unless substantial efficiency is found in the engine optimisation, generation and storage.

Re: Israeli Researchers Produce Green Hydrogen with 90% Efficiency

#26

Post by someplaceguy »

bkor wrote: post #19
mustafa_pasi wrote: post #14

Earlier quoted context omitted.

The obsession with efficiency is disingenuous too. The two limiting factors are generation capacity and cost/economics. Efficiency by itself says nothing. In the early 1900s, gas was less efficient than electricity too, but for a whole century gasoline powered transportation was more feasible. Aviation is still only feasible with kerosene despite it being less efficient than electric propulsion.

Efficiency has a huge impact on the cost/economics, something that you've highlighted. If significant more energy is needed, it'll likely be more expensive. Hydrogen is sometimes only a third as efficient as other solutions. It's pretty logical to assume it'll be > In the early 1900s, gas was less efficient than electricity too I think you mean gasoline instead of just gas. Hydrogen requires huge amounts of energy be…

> Efficiency has a huge impact on the cost/economics

It doesn't have nearly as much impact as other factors, such as abundance of the material, how easy/practical it is to work with it (which influences both demand and supply), whether mass infrastructure for it already exists (although this is more relevant in the short-term rather than long-term), etc.

These factors impact the economics of an energy source much more than efficiency, and economics is by far the most important factor in deciding whether an energy source will be used or not (and how much of it), not efficiency.

e.g. if hydrogen is only 10% efficient but there's 10 times more of it on Earth compared to a similar energy source that is 90% efficient, then hydrogen wins (all other factors being equal).

As another example, if hydrogen tanks in cars explode 100 times as often as gas tanks, then it would probably be a complete non-starter for powering vehicles, regardless of efficiency.

Re: Israeli Researchers Produce Green Hydrogen with 90% Efficiency

#27

Post by xgl5k »

bkor wrote: post #19
mustafa_pasi wrote: post #14

Earlier quoted context omitted.

The obsession with efficiency is disingenuous too. The two limiting factors are generation capacity and cost/economics. Efficiency by itself says nothing. In the early 1900s, gas was less efficient than electricity too, but for a whole century gasoline powered transportation was more feasible. Aviation is still only feasible with kerosene despite it being less efficient than electric propulsion.

Efficiency has a huge impact on the cost/economics, something that you've highlighted. If significant more energy is needed, it'll likely be more expensive. Hydrogen is sometimes only a third as efficient as other solutions. It's pretty logical to assume it'll be > In the early 1900s, gas was less efficient than electricity too I think you mean gasoline instead of just gas. Hydrogen requires huge amounts of energy be…

Efficiency is important for cost/economics but so is the abundance/scarcity. Fossil fuels are a non-renewable resource and are in theory supposed to get more scarce in the future driving up costs/economics while hydrogen is the most abundant element. Granted it is more cumbersome to capture, transport, store, and distribute it now, I don't think it's a outlandish theory that at some point in the future, technological improvement in hydrogen industry combined with more scarcity of oil could change the calculus on the cost/economics of oil vs hydrogen.

Re: Israeli Researchers Produce Green Hydrogen with 90% Efficiency

#28

Post by mustafa_pasi »

boringg wrote: post #8

They miss another core argument the cost to transport and store it is quite high.

This is not true at all. The cost of storage scales very well for hydrogen, must better than any other alternative. Transportation is context dependent. If you can build transmission lines, then do so. But hydrogen and synthetic fuels allow you to ship energy half way around the world. It is still the second best option even in that case.

Re: Israeli Researchers Produce Green Hydrogen with 90% Efficiency

#30

Post by thadjo »

I'm seeing a lot of people here assuming that the purpose of green hydrogen is for fuel cells / automotive transport, but I don't see many people in this space talking about that anymore (except Toyota).

Instead there is a lot more interest in using green hydrogen for industrial purposes or as a key building block for cleaner fuels like methanol. Currently green hydrogen is expensive to make and sucks to transport. But it will likely get a lot cheaper to produce in the next 10 years and you can convert it into fuels that are easier to transport.

There is recent episode of Volts that interviews a startup trying to do this: https://www.volts.wtf/p/making-shipping-fuel-with-off-grid#d...

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