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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

#131

Post by hkt »

wffurr wrote: post #116
_aavaa_ wrote: post #99

Earlier quoted context omitted.

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 .

I think their point for syngas (or better yet synthetic liquid fuels) is that solar will be so cheap that the efficiency won't matter.

Except that efficiency really does matter right now as energy demands are increasing globally

Re: Israeli Researchers Produce Green Hydrogen with 90% Efficiency

#132

Post by ben_w »

angiosperm wrote: post #95
biomcgary wrote: post #91

Earlier quoted context omitted.

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.

Given the power requirements of flight — they're fuel efficient per passenger-kilometre, but they have a lot of passengers and go a long distance — planes are the only place[0] where I think "overproduction by nearby solar farms" just isn't going to be a thing.

OPEC paving their deserts with PV and synthesising fuel (whatever that is: hydrogen, Sabatier methane, aluminium for burning) or just exporting that electricity along a 2m^2 cross section solid aluminium rod to the other side of the planet? Sure, plausible.

[0] I was going to say "and rockets", but then I realised we don't launch anything like as many rockets as we fly planes, so even then rockets might still be running on green hydrogen or methane derived from it.

Re: Israeli Researchers Produce Green Hydrogen with 90% Efficiency

#133

Post by mrpopo »

mustafa_pasi wrote: post #56
mrpopo wrote: post #39

Earlier quoted context omitted.

Not really, increasing energy efficiency is at the heart of many climate solutions. Clean energy is still scarce, and in the places where it isn't, for instance Germany, there is backlash against it. Not to mention that they aren't even close to being 100% renewable-powered (wind+solar 30%), not even close to have 100% EV market penetration (about 2%), not even close to have the theoretical capacity for a grid to pow…

Manufacturing a whole new vehicle with a huge ass battery that is more cost intensive to manufacturing than a comparable ICE, a vehicle that due to contemporary trends has to be a 5-ton lifted SUV, a vehicle that is going to be used by ONE person to commute to work along a fixed predetermined route, a vehicle that is going to be replaced after 3 years because this person have to have the newest four wheels on the lot…

Obviously reducing private car usage is a priority. I don't have a car, never owned one, and I'm absolutely in favour of severe restrictions.

Now, you have to acknowledge the world we live in, a total ban won't be feasible in the time-frame that we have to combat climate change. (And neither will an electric grid sufficiently powerful to power millions of green hydrogen-powered vehicles or 5-ton SUVs for that matter).

Not all EVs weigh 5 tons. Promoting (smaller) EVs for people who need them is a good thing.

Re: Israeli Researchers Produce Green Hydrogen with 90% Efficiency

#134

Post by pjc50 »

angiosperm wrote: post #78
pjc50 wrote: post #54

Earlier quoted context omitted.

> Existing aircraft will be wholly unable to compete on any route where LH2 aircraft operate ? Are you suggesting this will be a result of regulatory action? Since it would most likely be more expensive for the first decade, even if I gave you a tap on the airfield labelled "free H2"

It is because the very large difference in fuel weight for a flight leaves radically increased capacity for carrying paying freight. As LH2 produced on-site at airports gets cheaper than Jet-A fuel, the gap widens.

I'd need to see the numbers on this on joule/kg, and then allowing for the increased tankage size.

Re: Israeli Researchers Produce Green Hydrogen with 90% Efficiency

#135

Post by pjc50 »

rcarr wrote: post #106
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…

When I say nuclear, I don’t mean as the primary fuel source, but as a few strategically placed plants to serve as back up until large scale battery storage gets sufficiently commonplace until it is no longer needed. Eventually every house will have its own large battery and solar panels on its roof. In combination with grid battery storage, increased panel efficiencies and huge amounts of solar and wind farms eventua…

> a few strategically placed plants to serve as back up until large scale battery storage gets sufficiently commonplace until it is no longer needed

I suspect battery storage will reach that point before any nuclear plant started in the West today generates its first watt: about 10-15 years.

Re: Israeli Researchers Produce Green Hydrogen with 90% Efficiency

#136

Post by rcarr »

pjc50 wrote: post #135
rcarr wrote: post #106

Earlier quoted context omitted.

When I say nuclear, I don’t mean as the primary fuel source, but as a few strategically placed plants to serve as back up until large scale battery storage gets sufficiently commonplace until it is no longer needed. Eventually every house will have its own large battery and solar panels on its roof. In combination with grid battery storage, increased panel efficiencies and huge amounts of solar and wind farms eventua…

> a few strategically placed plants to serve as back up until large scale battery storage gets sufficiently commonplace until it is no longer needed I suspect battery storage will reach that point before any nuclear plant started in the West today generates its first watt: about 10-15 years.

I really hope so!

Re: Israeli Researchers Produce Green Hydrogen with 90% Efficiency

#137

Post by rcarr »

ben_w wrote: post #130
rcarr wrote: post #106

Earlier quoted context omitted.

When I say nuclear, I don’t mean as the primary fuel source, but as a few strategically placed plants to serve as back up until large scale battery storage gets sufficiently commonplace until it is no longer needed. Eventually every house will have its own large battery and solar panels on its roof. In combination with grid battery storage, increased panel efficiencies and huge amounts of solar and wind farms eventua…

> and then we can just pipe energy from the equator to where it’s needed. Superconductors aren't the limiting factor for that, on paper we can already make a 40,000 km long 0.5Ω power line for costs comparable to current annual fossil fuel mining (Chinese annual coal alone is expensive enough for the aluminium). The problem is geopolitics and that it's a megaproject.

Interesting, I knew there was talks about piping energy from Morocco/Sahara to the UK but didn't know anything about projected costs or feasibility. Politics is the worst.

Re: Israeli Researchers Produce Green Hydrogen with 90% Efficiency

#138

Post by boringg »

mustafa_pasi wrote: post #28
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.

You need to compress hydrogen and storage containers need to be specially built for H2. It requires more energy and specific tankers to be able to handle it under pressure.

It is a fuel which has that advantage in that is it does transport around the world and can utilized on the specific site intentioned.

That said it is expensive specifically for hydrogen relative to other fuels that don't need special handling/containers/pressurizing.

Re: Israeli Researchers Produce Green Hydrogen with 90% Efficiency

#139

Post by angiosperm »

ben_w wrote: post #132
angiosperm wrote: post #95

Earlier quoted context omitted.

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

Given the power requirements of flight — they're fuel efficient per passenger-kilometre, but they have a lot of passengers and go a long distance — planes are the only place[0] where I think "overproduction by nearby solar farms" just isn't going to be a thing. OPEC paving their deserts with PV and synthesising fuel (whatever that is: hydrogen, Sabatier methane, aluminium for burning) or just exporting that electrici…

Notably, SpaceX is making no visible effort to synthesize methane for their cans. The only gesture in that direction is an announced plan to buy a pre-fab methane refinery that could possibly be adapted to run Sabatier; but no hint at a solar farm to power it, or a place to put one. I guess they could build one across the border in Mexico? CH4 for Cape Canaveral is a separate problem. More likely the refinery will just purify mined LNG.

Solar and wind farms supplying international airports would probably need to send power via HVDC transmission lines. But, yes, the airports will need much more than just overage from the farms, and probably booster shipments of LH2 from farms in the tropics, besides. Imagine how big must be the project of refining, transporting, storing, and distributing kerosene to gates, today. Yet it is made almost invisible.

Re: Israeli Researchers Produce Green Hydrogen with 90% Efficiency

#140

Post by ben_w »

angiosperm wrote: post #139
ben_w wrote: post #132

Earlier quoted context omitted.

Given the power requirements of flight — they're fuel efficient per passenger-kilometre, but they have a lot of passengers and go a long distance — planes are the only place[0] where I think "overproduction by nearby solar farms" just isn't going to be a thing. OPEC paving their deserts with PV and synthesising fuel (whatever that is: hydrogen, Sabatier methane, aluminium for burning) or just exporting that electrici…

Notably, SpaceX is making no visible effort to synthesize methane for their cans. The only gesture in that direction is an announced plan to buy a pre-fab methane refinery that could possibly be adapted to run Sabatier; but no hint at a solar farm to power it, or a place to put one. I guess they could build one across the border in Mexico? CH4 for Cape Canaveral is a separate problem. More likely the refinery will ju…

For SpaceX in particular: if they don't do it, they're not going to Mars.

(That doesn't mean they will do it, it's just the consequence of failure).

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