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After many false starts, hydrogen power might now bear fruit

economist.com

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Re: After many false starts, hydrogen power might now bear fruit

#331

Post by CydeWeys »

Jedd wrote: post #237
CydeWeys wrote: post #234

Earlier quoted context omitted.

Is solar thermal still a going concern? Are new plants still being built?

It seems to be in a lull, but the technology is still maturing. I suspect as the generation + storage costs continue to shift, it'll be adopted more eagerly. PVCs cost reduction has been a boon for that industry, but that tech, of course, ignores the storage problem. Reading about some of the missteps of CSP, much like the above, they seem to be share similar traits of government mishandling, bureaucracy, dodgy deali…

Why wouldn't solar thermal have the exact same issue with mirrors getting dusty though?

I suspect that solar thermal is in more than a lull; I suspect that it's been obsoleted by PV and we aren't going to be seeing many new installations at all.

Re: After many false starts, hydrogen power might now bear fruit

#332

Post by [deleted] »

bogdanu wrote: post #69
jiofih wrote: post #44

Earlier quoted context omitted.

It pays off to read the comment fully before replying to it.

My reply was mostly meant only for the first 2 sentences, except the trucking part. I was trying to evidentiate that charging stations built by tesla supplement home charging or any normal outlet. It's a bit different than building a network of superchargers because the demand would be a lot higher because a hydrogen powered car will be fully dependent of those specially built charging stations. The main idea is that…

[deleted]

Re: After many false starts, hydrogen power might now bear fruit

#333

Post by jsilence »

MayeulC wrote: post #201
jsilence wrote: post #148

The explosion limits of hydrogen are very wide. I do not want to live in a world with a widely deployed hydrogen infrastructure. Stuff is going to blow up. People are going to die. Disclaimer: chemical engineer, German University.

People said that about electricity, too. A lot of people died. Houses burned. Norms were changed regarding cabling and earthing. Hopefully, whatever we decide to adopt as a technology will come with adequate safety norms. While only tangentially related, a lot of people think about the Hindenburg accident when talking about either hydrogen or dirigibles. But those contain less fuel than an airplane, at least in terms…

The physical threat ranges of electrocution and explosions vastly differ.

Re: After many false starts, hydrogen power might now bear fruit

#334

Post by ncmncm »

xyzzyz wrote: post #326
ncmncm wrote: post #320

Earlier quoted context omitted.

1. Electricity is getting cheaper all the time. The cheapest forms, wind and solar, involve no detour through heat. Anything that uses electricity instead of something that produces CO2 is a big net win. 2. Huge efficiency gains are to be had, in electrolysis, via catalytic action, needing only transition from lab to production funded by sufficient demand for the hydrogen. 3. There has been great success with direct…

Yes, it is conceivable that you could use cheap electricity from renewables, but it would have to be a lot cheaper than electricity from natural gas for it to make economic sense, probably something on the order of 5-6x cheaper. You get a factor of 3x just by using natural gas to heat directly, and then you need to account for bigger capital expenses for building plant and storage, because the cheap renewables are no…

It is a mystery to me why you keep talking about heat. Heat is the lowest grade of energy, and least useful. Not taking a wasteful detour through heat is the first rule of efficient conversion.

While duty cycle of solar is under 50%, when there is not sunshine there is very often wind. So 50% idle capacity is unlikely.

Catalytic conversion of electricity to hydrogen will probably exceed 90% efficiency in short order, and from H2 back to electric via fuel cell is already over 90%.

Liquified and pumped into aircraft, nothing comes close to H2 for efficiency. Likewise, in rockets.

When we finally get sensible carbon taxation, 6x cheaper than CH4 will be easy to achieve.

Re: After many false starts, hydrogen power might now bear fruit

#335

Post by Jedd »

CydeWeys wrote: post #331
Jedd wrote: post #237

Earlier quoted context omitted.

It seems to be in a lull, but the technology is still maturing. I suspect as the generation + storage costs continue to shift, it'll be adopted more eagerly. PVCs cost reduction has been a boon for that industry, but that tech, of course, ignores the storage problem. Reading about some of the missteps of CSP, much like the above, they seem to be share similar traits of government mishandling, bureaucracy, dodgy deali…

Why wouldn't solar thermal have the exact same issue with mirrors getting dusty though? I suspect that solar thermal is in more than a lull; I suspect that it's been obsoleted by PV and we aren't going to be seeing many new installations at all.

I suspect there's several answers to your first question. For example, the mechanical factor of parabolic mirrors that are typically used for CSP's - they can provide more shelter in terms of wind-deposited dust than flat panels all angled in the same direction (a la PV panels).

I also suspect that mirrors are less sensitive to dust than PV cells. And that it's cheaper to just install more mirrors (flat reflective surfaces) to compensate for anticipated dust build-up, than photovoltaic panels (per unit of area or per unit of power generated).

But, really, I expect there's a fair bit of research on this subject already out there.

As I intimated, it's probably not so much an obsolescence issue, as one of pushing the storage question aside. CSPs address generation, with some ephemeral (cloud, evening, etc) storage capabilities. As per the standard observation - it's going to be a blend of power generation and storage technologies that sees us through.

Re: After many false starts, hydrogen power might now bear fruit

#336

Post by xyzzyz »

ncmncm wrote: post #334
xyzzyz wrote: post #326

Earlier quoted context omitted.

Yes, it is conceivable that you could use cheap electricity from renewables, but it would have to be a lot cheaper than electricity from natural gas for it to make economic sense, probably something on the order of 5-6x cheaper. You get a factor of 3x just by using natural gas to heat directly, and then you need to account for bigger capital expenses for building plant and storage, because the cheap renewables are no…

It is a mystery to me why you keep talking about heat. Heat is the lowest grade of energy, and least useful. Not taking a wasteful detour through heat is the first rule of efficient conversion. While duty cycle of solar is under 50%, when there is not sunshine there is very often wind. So 50% idle capacity is unlikely. Catalytic conversion of electricity to hydrogen will probably exceed 90% efficiency in short order,…

It is a mystery to me why you keep talking about heat. Heat is the lowest grade of energy, and least useful. Not taking a wasteful detour through heat is the first rule of efficient conversion.

That’s because the alternative process to electrolysis of producing hydrogen, the steam reforming, uses heat, not electricity. I keep talking about heat, because electricity from solar or wind is competing not with electricity from natural gas, but with heat from natural gas. Given typical conversion efficiency of 20-30%, this means that the heat from natural gas is at the very least 3-5 times cheaper than electricity from natural gas, and in fact it’s even cheaper than that, because you don’t need expensive turbines to generate heat from natural gas, reducing your capital and maintenance costs even more. EIA doesnt expect costs of electricity from solar to go below electricity from natural gas by 2040 at all, much less 6 times.

When we finally get sensible carbon taxation, 6x cheaper than CH4 will be easy to achieve.

Yes, if you put a finger on a scale, you can achieve any result that you want.

Re: After many false starts, hydrogen power might now bear fruit

#337

Post by ncmncm »

xyzzyz wrote: post #336
ncmncm wrote: post #334

Earlier quoted context omitted.

It is a mystery to me why you keep talking about heat. Heat is the lowest grade of energy, and least useful. Not taking a wasteful detour through heat is the first rule of efficient conversion. While duty cycle of solar is under 50%, when there is not sunshine there is very often wind. So 50% idle capacity is unlikely. Catalytic conversion of electricity to hydrogen will probably exceed 90% efficiency in short order,…

It is a mystery to me why you keep talking about heat. Heat is the lowest grade of energy, and least useful. Not taking a wasteful detour through heat is the first rule of efficient conversion. That’s because the alternative process to electrolysis of producing hydrogen, the steam reforming, uses heat, not electricity. I keep talking about heat, because electricity from solar or wind is competing not with electricity…

I guess you meant to say "finger off the scale", after carbon burners are no longer permitted to externalize environmental damage for free. If it had been collected starting when we knew it would cause catastrophe, and commensurate with the catastrophe, we would be carbon-negative by now. Clawing it back, retroactively, from those enriched by causing the catastrophe would be helpful even now.

Re: After many false starts, hydrogen power might now bear fruit

#338

Post by Jedd »

igravious wrote: post #328
Jedd wrote: post #283

Earlier quoted context omitted.

> Amen. Not just bad faith; ignorant, myopic and ahistorical. Referring to GP's wikipedia reference, can you explain the two 'for unknown reasons' on a) why the original (Canadian) contract was not engaged, and b) the Turkish project was not engaged. What precisely was ashistorical about any of my post? > > this sounds like a traditional government project problem -- susceptibility to corruption, vanity, hubris etc.…

Please go grind your axe somewhere else.

I'm assuming that since axes weren't government inventions that we're allowed to talk about them?

Re: After many false starts, hydrogen power might now bear fruit

#339

Post by CydeWeys »

Jedd wrote: post #335
CydeWeys wrote: post #331

Earlier quoted context omitted.

Why wouldn't solar thermal have the exact same issue with mirrors getting dusty though? I suspect that solar thermal is in more than a lull; I suspect that it's been obsoleted by PV and we aren't going to be seeing many new installations at all.

I suspect there's several answers to your first question. For example, the mechanical factor of parabolic mirrors that are typically used for CSP's - they can provide more shelter in terms of wind-deposited dust than flat panels all angled in the same direction (a la PV panels). I also suspect that mirrors are less sensitive to dust than PV cells. And that it's cheaper to just install more mirrors (flat reflective su…

Good points. I still think that, overall, money talks, and the vast majority of solar installations are not managed nearly as incompetently as this one was (i.e. not forgetting to take into account sand in a desert). So the fact that close to 100% if not 100% of new solar installations are PV over solar thermal really does mean that once you take all these factors into account, PV is still more cost-effective.

The storage issue is interesting, but doesn't matter so much to most plants since they tie into a larger balanced grid, and battery storage is coming down in cost at the same exponential rate as PV. These same advantages are not accruing to solar thermal. So I do think we are seeing the death knell for solar thermal, even when energy storage is desired alongside peak production.

Re: After many false starts, hydrogen power might now bear fruit

#340

Post by Jedd »

CydeWeys wrote: post #339
Jedd wrote: post #335

Earlier quoted context omitted.

I suspect there's several answers to your first question. For example, the mechanical factor of parabolic mirrors that are typically used for CSP's - they can provide more shelter in terms of wind-deposited dust than flat panels all angled in the same direction (a la PV panels). I also suspect that mirrors are less sensitive to dust than PV cells. And that it's cheaper to just install more mirrors (flat reflective su…

Good points. I still think that, overall, money talks, and the vast majority of solar installations are not managed nearly as incompetently as this one was (i.e. not forgetting to take into account sand in a desert). So the fact that close to 100% if not 100% of new solar installations are PV over solar thermal really does mean that once you take all these factors into account, PV is still more cost-effective. The st…

Agree up to a point.

Storage can't be ignored - and the 'balanced grid' that we're all part of relies heavily on burning fossil fuels for both baseload coping with peaks (sun goes behind a cloud or the horizon, or the wind stops for a while). As we decom more of the fossil fuel systems, a more robust & scalable storage system, even a relatively ephemeral one, will become more compelling. (my prediction : )

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