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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

#91

Post by biomcgary »

angiosperm wrote: post #75
purpleflame1257 wrote: post #61

Earlier quoted context omitted.

I am fairly sure this is due to the necessity of having pressurized cylindrical storage for the hydrogen. Fitting that kind of tank into the wings is going to be hard.

Tanks would be wholly impossible to fit into the wings. Thus, the under-wing nacelles. But pressure cylinders are a non-starter, because they are heavy. Expect to see, instead, insulated, unpressurized LH2 tanks.

The common criticism of LH2 economics is the energy required for liquification. Are you assuming that this is taken care of by overbuilding solar/wind and creating LH2 opportunistically?

Re: Israeli Researchers Produce Green Hydrogen with 90% Efficiency

#92

Post by _hypx »

jandrese wrote: post #82
MrVitaliy wrote: post #46

Earlier quoted context omitted.

I'm hopeful for hydrogen use in aviation. Either that or some ridiculous breakthrough in battery tech, and the latter seems less likely than former.

I think hydrogen for aviation is probably a dead end. I suspect the long term solution for aviation, at least long haul, is biofuels. Battery tech is edging into the realm where it could be used for short haul flights, but we have quite a ways to go before you'll be able to fly across the Pacific, or even Atlantic, on a single charge with reasonable passenger comfort.

Biofuels are fundamentally not green. You might as well suggest we use fossil fuels forever.

Re: Israeli Researchers Produce Green Hydrogen with 90% Efficiency

#93

Post by efitz »

rfgmendoza wrote: post #84
surgical_fire wrote: post #79

Earlier quoted context omitted.

I favor nuclear. It is clean, reliable, and surprisingly safe, especially with all the regulations on the sector. But it was never, and will never be "cheap". Also not all places might be suitable for nuclear, for various reasons. Hydrogen might be a good option.

nuclear isn't cheap if you are thinking about the cost to build out a new plant under current design. but the per kw cost is relatively low as i understand it since the fuel is so efficient and its getting cheaper as new reactor designs get cheaper and safer

I wonder how much of the cost of nuclear is regulatory and lawfare related rather than intrinsic.

Re: Israeli Researchers Produce Green Hydrogen with 90% Efficiency

#94

Post by _hypx »

rcarr wrote: post #38

Obviously hydrogen has it's uses, but a large part of me feels the energy industry is stalling for time. Oil and gas is basically a subscription model, whereas electric cars and heat pumps are buy once, upgrade in x years or when broken model. With enough renewable energy and a few nuclear power plants, electricity should be ridiculously cheap and if they've got the space, the consumer can even generate their own. Th…

BEVs are the biggest example of greenwashing today. You will need a vast increase in raw material demand and it is arguably completely unsustainable. Especially once you realize that we are making battery powered SUVs.

In reality, people are spreading a conspiracy theory to mentally distract from this fact. They do not want to admit that they have been fooled by battery makers, so they create a narrative that the alternative is somehow an ever bigger scam.

Re: Israeli Researchers Produce Green Hydrogen with 90% Efficiency

#95

Post by angiosperm »

biomcgary wrote: post #91
angiosperm wrote: post #75

Earlier quoted context omitted.

Tanks would be wholly impossible to fit into the wings. Thus, the under-wing nacelles. But pressure cylinders are a non-starter, because they are heavy. Expect to see, instead, insulated, unpressurized LH2 tanks.

The common criticism of LH2 economics is the energy required for liquification. Are you assuming that this is taken care of by overbuilding solar/wind and creating LH2 opportunistically?

Much the way aluminum producers guarantee load for hydro power producers, airports will consume overproduction by nearby solar farms.

Re: Israeli Researchers Produce Green Hydrogen with 90% Efficiency

#96

Post by traverseda »

_hypx wrote: post #92
jandrese wrote: post #82

Earlier quoted context omitted.

I think hydrogen for aviation is probably a dead end. I suspect the long term solution for aviation, at least long haul, is biofuels. Battery tech is edging into the realm where it could be used for short haul flights, but we have quite a ways to go before you'll be able to fly across the Pacific, or even Atlantic, on a single charge with reasonable passenger comfort.

Biofuels are fundamentally not green. You might as well suggest we use fossil fuels forever.

What do you mean? The fuel itself should be carbon neutral, even if it requires extra energy to create. I don't see any reason you couldn't make carbon neutral bio fuel, although I'd net on syngas instead.

Re: Israeli Researchers Produce Green Hydrogen with 90% Efficiency

#97

Post by AnthonyMouse »

slashdev wrote: post #53
pjc50 wrote: post #49

Earlier quoted context omitted.

> few nuclear power plants, electricity should be ridiculously cheap Nuclear has never managed to be cheap. The really big nuclear buildouts always had a national security subsidy: either for energy security (France), or for nuclear weapons (US, UK, USSR, China, and also France). This is partly why non-weaponizable reactor designs never became popular either. > They obviously don't like that, which is why they keep p…

As much as I’ve been rooting for nuclear, I think the ship has sailed. If newer advances can’t make it cost competitive with renewables plus some storage (I’ll get to that in a minute) then why would you ever deploy it. Renewables are really cheap and getting cheaper, so some combination of overbuild with storage is probably the winning formula. Storage is a little too expensive as lithium ion batteries, but there’s…

> If newer advances can’t make it cost competitive

Did they ever get rid of the rule that prohibits nuclear from being cost competitive? Its opponents got it so if they ever found a way to make it cost less the money explicitly had to be spent on new safety measures. Which obviously not only makes it impossible to reduce the cost but also removes any incentive to try.

Re: Israeli Researchers Produce Green Hydrogen with 90% Efficiency

#98

Post by _aavaa_ »

mustafa_pasi wrote: post #14
_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…

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.

Yes, gasoline won because it was more convenient.

Hydrogen (and explosive gas which is notorious difficult to transport and work with safely) is neither efficient nor convenient.

Re: Israeli Researchers Produce Green Hydrogen with 90% Efficiency

#99

Post by _aavaa_ »

wffurr wrote: post #41
hkt wrote: post #17

Earlier quoted context omitted.

100% this. Few people have been able to answer the question of "how does it compare to a heat pump that has a SCOP of 4?" without me having to fight the urge to roll my eyes. By the time (highly explosive) hydrogen gets into people's homes I'd be surprised if it was even 20% as efficient as a heat pump.

You would use hydrogen to produce methane to then burn in people's existing as furnaces using the existing natural gas distribution infrastructure. That seems to be Terraform's plan. Still seems better to me to convert as much housing as possible to heat pumps, which seem much better fit for purpose than on-site combustion. I think green hydrogen has a lot more potential as a precursor to liquid fuels for e.g. aviati…

If you're going to convert it into methane and burn it you'll make a fuel cell's ~37% round trip efficiency look massive.

turning it into methane to burn it is trying to solve last century's problem. People need way to stay warm not things to burn.

Re: Israeli Researchers Produce Green Hydrogen with 90% Efficiency

#100

Post by jakewins »

AnthonyMouse wrote: post #97
slashdev wrote: post #53

Earlier quoted context omitted.

As much as I’ve been rooting for nuclear, I think the ship has sailed. If newer advances can’t make it cost competitive with renewables plus some storage (I’ll get to that in a minute) then why would you ever deploy it. Renewables are really cheap and getting cheaper, so some combination of overbuild with storage is probably the winning formula. Storage is a little too expensive as lithium ion batteries, but there’s…

> If newer advances can’t make it cost competitive Did they ever get rid of the rule that prohibits nuclear from being cost competitive? Its opponents got it so if they ever found a way to make it cost less the money explicitly had to be spent on new safety measures. Which obviously not only makes it impossible to reduce the cost but also removes any incentive to try.

What legal jurisdiction are you saying this was a rule in? I’ve never heard of this
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