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Cheap, green hydrogen would be a breakthrough in clean energy

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Re: Cheap, green hydrogen would be a breakthrough in clean energy

#241

Post by elihu »

throw_nbvc1234 wrote: post #136
elihu wrote: post #93

Earlier quoted context omitted.

Having some cheap long-term energy storage option is one way to solve that problem, but another is better power grid interconnection. For instance, Chicago could get solar power from Chile in the winter time to buffer out the seasonal variability. Or if they didn't even want to have to maintain a smaller buffer to deal with day/night cycles, they could get solar power from, say, Algeria and Australia depending on tim…

How would you factor in Geo-political risks to this approach? Seems like we're trading dependency on oil producing countries with a dependency on "sunny and windy" countries. Arguably worse unless the grid is connected like a mesh. Quick google shows that 61% of oil is transported by sea. Non-mesh power-grid interconnection is the equivalent of an oil pipeline with the geo-political downsides associated with it. Thou…

I think the right way to mitigate the risk is to keep many/most of the fossil fuel plants around so that they can be brought online in an emergency (i.e. someone destroys a cable), but otherwise don't use them.

Re: Cheap, green hydrogen would be a breakthrough in clean energy

#242

Post by midasuni »

yvdriess wrote: post #222
midasuni wrote: post #187

Earlier quoted context omitted.

A modern heat pump claims a cop in the 4.8 range It’s more efficient to burn the gas in a grid power station, convert to electricity, and use the electricity to drive the heat pump, then it is to burn the gas for heat directly.

Watch out, cop ranges wildly (1.1-5+) depending on the type of heat pump, output temperature and intake temperature. Ideal are water-water heat pumps connected to a deep well, but these cannot be installed everywhere and carry a significant (roughly double) capital investment. Air-water heat pumps are very sensitive to outside air temperature and output temperature. Low-temperature heating (30-40C) still gets an OK ~…

Specs on this one

https://www.panasonicproclub.com/uploads/IE/catalogues/PIR%2...

Show a 4.5 cop for a 7C-35C range, dropping to 1.8 for a -7 to 55C range.

For 2C to 35C it’s still a cop over 3

Re: Cheap, green hydrogen would be a breakthrough in clean energy

#243

Post by ncmncm »

jacquesm wrote: post #204
ncmncm wrote: post #95

Earlier quoted context omitted.

My father reports feeding raw ammonia directly into furrows being cut. Yes, a leaky ammonia tank would be a problem, but it is not exactly odorless.

By the time you can smell it from a leaking tank depending on the speed of the spill you may already be inviting lung damage, if it overwhelms you you're as good as dead. With some regularity farmers here are overcome by ammonia that has pooled in manure storage pools. This article starts up with 'three dead per year through fertilizer vapors, one breath and you are gone'. https://www.rtlnieuws.nl/nieuws/nederland/ar…

Three from a population of how many? Compared to how many in some other possible world?

As long as people are being killed in numbers many orders of magnitude greater, just so sugar sellers will have good quarterly profits, it will be hard to count those.

Re: Cheap, green hydrogen would be a breakthrough in clean energy

#244

Post by elihu »

ClumsyPilot wrote: post #118
elihu wrote: post #93

Earlier quoted context omitted.

Having some cheap long-term energy storage option is one way to solve that problem, but another is better power grid interconnection. For instance, Chicago could get solar power from Chile in the winter time to buffer out the seasonal variability. Or if they didn't even want to have to maintain a smaller buffer to deal with day/night cycles, they could get solar power from, say, Algeria and Australia depending on tim…

"they could get solar power from, say, Algeria and Australia depending on time of day." This is basically a proposal to power all of Americas at night using solar deployment in Australia? This is far outside the realm of technical and infrastructural feasability. What about reliability? UK power connection to france has burned down a few months ago and it will take 2 years to fix, and it only moves like 2 GW

I would have thought so too, but there was a story awhile back about China working out a deal with Chile to import solar power from Chile via a trans-Pacific cable. Maybe it's just hype and nothing will actually come of it, but someone at least seems to think it's plausible.

https://www.pv-magazine.com/2021/11/15/chile-wants-to-export...

Probably the way to handle reliability is to keep some of the fossil fuel plants in operational condition just in case. If everything is working properly they don't have to ever be used, but countries aren't under continual threat that their energy supply is going to be cut because someone damaged the cable (accidentally or deliberately).

Re: Cheap, green hydrogen would be a breakthrough in clean energy

#245

Post by chicob »

ncmncm wrote: post #240
kkfx wrote: post #236

Earlier quoted context omitted.

I imaging hydrogen can be stored, but not for long, witch means we store it and slowly it "evaporate" going through the tank. BTW let's talk about an example: Toyota Mirai, far complex than an EV, complex than an ICE, ~1kg H₂ / 100 km. Now let's say we have spend 67kWh of green electricity to produce that kg of H₂, the process have some loss, again I can't really know how much but some [1] say are around 14%, not bad…

Let's not rely on your imagination. Hydrogen is stored. The amount that leaks can be as small as you like. Actual loss as a percentage of what you put in is always negligible. The point often made about leaks is just that H2 must not be allowed to accumulate, so needs positive airflow to prevent detonations. Mirai is just an electric car with an H2 tank, a fuel cell, and a small battery. The fuel cell has no moving p…

«The kWh that goes into a unit of H2 will not matter much, because it is just sunshine and wind.»

Exactly. And that also means that eventual losses, arising from intrinsic inefficiency, won't have an impact on the environment, which is the main point.

Re: Cheap, green hydrogen would be a breakthrough in clean energy

#246

Post by Jabihjo »

ad404b8a372f2b9 wrote: post #148
ggm wrote: post #147

The FF industry is leaping (has leapt, historically) on CCS as a getout clause and has sunk french metric tonnes of money into CCS. So far, its uneconomic except for the specific use of pumping gas into wells to make them more productive, which leads to more fugitive gas. No significant CCS experiment worldwide has achieved its goals as sequestration. The one in Western Australia releases so much CO2 it has to pay a…

FF: fossil fuel. CCS: carbon capture and storage.

FFS..for fucks sake

Re: Cheap, green hydrogen would be a breakthrough in clean energy

#247

Post by kkfx »

ncmncm wrote: post #240
kkfx wrote: post #236

Earlier quoted context omitted.

I imaging hydrogen can be stored, but not for long, witch means we store it and slowly it "evaporate" going through the tank. BTW let's talk about an example: Toyota Mirai, far complex than an EV, complex than an ICE, ~1kg H₂ / 100 km. Now let's say we have spend 67kWh of green electricity to produce that kg of H₂, the process have some loss, again I can't really know how much but some [1] say are around 14%, not bad…

Let's not rely on your imagination. Hydrogen is stored. The amount that leaks can be as small as you like. Actual loss as a percentage of what you put in is always negligible. The point often made about leaks is just that H2 must not be allowed to accumulate, so needs positive airflow to prevent detonations. Mirai is just an electric car with an H2 tank, a fuel cell, and a small battery. The fuel cell has no moving p…

Hydrogen leak because it's damn small, so you tank can hold it as a not-watertight tank can hold water, for a certain amount of time but not forever. We have tempted various routes, micro-foams included, none succeed completely. Surely as long as there is no accumulation risk H₂ leaks are harmless, but you still loose something valuable for you.

kWh also matter MUCH: personally I can potentially produce just few grams of H₂ in a good sunny day from my p.v. witch happen to be perfectly capable of recharging an EV in a sunny day.

Try this: a classic home is cheap, but demand much energy. A modern one is far more expensive, but demand far less. Now if spending for good insulation, airtightness, relevant windows, VMC, water-heater with heat-pump + solar, a p.v. system and an EV means an initial investment of around 150% more than a classic house with a classic ICE, you can't pay it back much before EV battery is dead but anyway it's doable. If you want to add to the mix H₂ perhaps as a way to pass trough nights and non-sunny days the overall costs climb around 400%. It's essentially unsustainable for single individuals/families AND it's unsustainable for the society on scale. That's is.

Producing, compressing etc enough H₂ to power a personal vehicle means having a 20kWp p.v. at home and using the vehicle only in sunny days from spring to summer. All equipment's would costs twice the house itself. Try to do the math for a truck and even more for a plane. Also try to consider how much fuel-cells we can make on scale, since they ALSO demand rare and precious elements.

Re: Cheap, green hydrogen would be a breakthrough in clean energy

#248

Post by jacquesm »

ncmncm wrote: post #243
jacquesm wrote: post #204

Earlier quoted context omitted.

By the time you can smell it from a leaking tank depending on the speed of the spill you may already be inviting lung damage, if it overwhelms you you're as good as dead. With some regularity farmers here are overcome by ammonia that has pooled in manure storage pools. This article starts up with 'three dead per year through fertilizer vapors, one breath and you are gone'. https://www.rtlnieuws.nl/nieuws/nederland/ar…

Three from a population of how many? Compared to how many in some other possible world? As long as people are being killed in numbers many orders of magnitude greater, just so sugar sellers will have good quarterly profits, it will be hard to count those.

That's now how it works though. If you lump all of the preventable deaths in a profession together it starts to add up, and NL is efficient enough that three people in a population of 10K farmers, a much smaller fraction of which is into animals is high enough to be noticed. Farming is a dangerous profession (lots of open rotating machinery) and we value life enough that doing something about things like this (workplace accidents) is strongly culturally ingrained.

It's also an entirely different domain from the 'sugar sellers'.

Re: Cheap, green hydrogen would be a breakthrough in clean energy

#249

Post by ncmncm »

kkfx wrote: post #247
ncmncm wrote: post #240

Earlier quoted context omitted.

Let's not rely on your imagination. Hydrogen is stored. The amount that leaks can be as small as you like. Actual loss as a percentage of what you put in is always negligible. The point often made about leaks is just that H2 must not be allowed to accumulate, so needs positive airflow to prevent detonations. Mirai is just an electric car with an H2 tank, a fuel cell, and a small battery. The fuel cell has no moving p…

Hydrogen leak because it's damn small, so you tank can hold it as a not-watertight tank can hold water, for a certain amount of time but not forever. We have tempted various routes, micro-foams included, none succeed completely. Surely as long as there is no accumulation risk H₂ leaks are harmless, but you still loose something valuable for you. kWh also matter MUCH: personally I can potentially produce just few gram…

kWh matters MUCH to you, not to reasonable people. If you need more H2, use a better electrolyser, or add another panel or two.

The fact is, your numbers are all way off, so do not produce sensible judgments. They make you seem nutters. Get better numbers.

Re: Cheap, green hydrogen would be a breakthrough in clean energy

#250

Post by sitkack »

ggm wrote: post #147

The FF industry is leaping (has leapt, historically) on CCS as a getout clause and has sunk french metric tonnes of money into CCS. So far, its uneconomic except for the specific use of pumping gas into wells to make them more productive, which leads to more fugitive gas. No significant CCS experiment worldwide has achieved its goals as sequestration. The one in Western Australia releases so much CO2 it has to pay a…

Gates knows exactly what he is doing. Same Gates, different pasture.
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