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EU drafts plan to label gas and nuclear investments as green

reuters.com

431–440 of 451 posts

Re: EU drafts plan to label gas and nuclear investments as green

#431

Earlier quoted context omitted.

Yes, and you can argue that coal and oil are currently being created... very slowly... from dead trees and what not. So renewable vs non-renewable doesn't make any sense anymore. Lets make another name: "energy which source can get replenished in less than 100 years (a life time), as wood, or less, as solar, wind, waves, and can be practically harvested with current methods i.e. not fussion or matter dissolved in the…

Solar isn't something that can ever be replenished. There's a fixed quantity of fuel in the sun. Once it burns out, it's gone. That provides the input energy into the process for solar, wind and wood. With breeder reactors the uranium in seawater would last us 15 million years at current nuclear power consumption levels. If that's not renewable... There's no such thing as infinitely renewable.

I though it was already clear that we were talking human scale. And you still talk about 4,500 million years as non-renewable, but 15 million years (plus 100% magic ocean harvesting) as renewable. At no point anybody said "infinitely renewable", and you arguing it makes that a strawman argument.

Renewable is defined, like it or not, as a source that replenishes in a finite human scale (roughly, 50-100 years). Sun, waves, hydraulics and wind "replenish" everyday. Wood takes about 30 years. If you find yourself saying things like "15 millions years" or "60,000" years, it's not renewable.

Re: EU drafts plan to label gas and nuclear investments as green

#432

Earlier quoted context omitted.

Yes, solar has emissions. But in your previous message you implied that it is larger than it is by making a deceptively long list of items. These are the number of total CO2 emited per energy produced (gCO2e/kWh): - Nuclear and eolic, 4. - Solar, 6. - Gas CCS, 78. - Hydro, 97. - Coal CCS, 109. Citation, as requested: https://www.nature.com/articles/s41560-017-0032-9 Implying that solar, nuclear or wind have emissions…

> But in your previous message you implied that it is larger than it is by making a deceptively long list of items. No I didn’t. Your reading comprehension did that. I was simply pointing out that a dipshit stance like “no energy source can have any emissions and be called green” actually rules everything out and destroys the nuanced discussions between green energies. The statement I replied to was literally “It is…

The message I answered was to support that CO2 emited by solar, wind or nuclear are indeed minute compared with a gas plant, even including "short of a life, manufacturing, transport, installation, and disposal" emissions.

Because someone reading that long list of items could get confused and think that those things added so much emissions that they could be near fossil emisions. It seems that it was not your intention, but I felt a clarification and a citation was needed.

Re: EU drafts plan to label gas and nuclear investments as green

#433
post #83

Earlier quoted context omitted.

Natural gas can be green and reduce global warming… in the specific case where you burn methane that would have otherwise escaped to the atmosphere. Garbage dumps are a very good case to burn natural gas, get energy, and slow help the climate. But these sources are limited.

I believe that "natural gas" only refers to fossil gas, and other sources of Methane already have (different) marketing terms.

They are called "biogas" and considered renewable.

Re: EU drafts plan to label gas and nuclear investments as green

#434
post #364

Earlier quoted context omitted.

10 more years is needed if you want nuclear. Possibly also batteries, but that’s harder for me to estimate — we’ve got the price down, but we need way more volume.

It would take mere months to open back up those plants recently closed. Back in the 70s they could construct plants in 2-5 years. Chernobyl 1 began and completed construction in the same year! Has our technology gotten worse since then? Or is it just permits and bureaucracy impeding us?

This is worldwide, not localised to one specific nation, so likely we created the bureaucracy for good reasons.

Re: EU drafts plan to label gas and nuclear investments as green

#435
post #271

Earlier quoted context omitted.

This is as close to arguing about what colour to paint the deck chairs on the titanic as I can imagine. A non-carbon neutral source of energy is not any shade of green, until we’ve averted the upcoming climate disaster. And then maybe we can debate about how to spend our limited carbon budget.

Replacing coal with these and nukes while renewables are still being built (at greater speed than ever) is still an improvement.

Putting a coat of paint on the house the week before it has to be demolished is technically an improvement as well.

Re: EU drafts plan to label gas and nuclear investments as green

#436
post #415

Earlier quoted context omitted.

I'm curious on why you're pessimistic on hydrogen. I agree that cars are likely not the best use of fuel cells (heavy vehicles are able to utilize H2's strengths much more), but in a future based on renewables hydrogen allows you to store energy in a very dense way. Lithium batteries are acceptably heavy/expensive at small scales, but how do you think will supply vary to meet demand in the medium-long term without a…

Firstly, the energy density of hydrogen is a lie. Yes, the fuel itself has the highest know energy content per mass, but it's nearly useless as a gas. To reach any useful volume density you need a high pressure COPV tank that weights an other of magnitude more than the fuel it contains. To generate electricity you need a bulky fuel cell with low efficiency, which in turn requires a very beefy cooling system, larger t…

A COPV has about 6% hydrogen by mass. At 33.3 kWh/kg, that’s ~2000 Wh/kg. This is far beyond the theoretical limits of li-ion batteries.

Platinum is not a critical component, only necessary in current PEM fuel cells. Future fuel cells should eventually do away with platinum altogether. As hydrogen is effectively limitless too this is never going to be a resource concern.

Re: EU drafts plan to label gas and nuclear investments as green

#437

Earlier quoted context omitted.

The argument would be that if you didn’t provide that out market forces would force us into renewables more quickly.

Sure yeah. The politics of that (i.e. pretty much everyone seeing massive increases in their heating, electricity and fuel costs) would lead to a backlash and actually lead to less action over the longer term. That's the theory anyway, and if we look at what happened in France with fuel taxes, it seems pretty plausible to me.

[deleted]

Re: EU drafts plan to label gas and nuclear investments as green

#438
post #73

Earlier quoted context omitted.

Intuitively 270g per kWh seemed high to me, but to put it in perspective a Tesla model 3 does about 100km per 11.9~14.9kWh (according to Google). So taking the larger estimate (and ignoring transmission etc losses) at 270g/KWh that gives emissions of around 41g/km. Comparatively though my 2021 Camry hybrid has emissions of 96g/km. So, assuming the plants are primarily being used to level out variable renewable produc…

All very high numbers. The key to solving climate change isn't to do as before, just slightly more efficient. Electric cars won't solve anything, especially not if they are indirectly powered by fossil fuels. Make cities walkable, bikeable and public transportable. That will have far bigger impact than people buying new electric cars.

> Electric cars won't solve anything, especially not if they are indirectly powered by fossil fuels.

If they are not indirectly powered by fossil fuels then they will solve the problem.

Re: EU drafts plan to label gas and nuclear investments as green

#439
post #436
post #415

Earlier quoted context omitted.

Firstly, the energy density of hydrogen is a lie. Yes, the fuel itself has the highest know energy content per mass, but it's nearly useless as a gas. To reach any useful volume density you need a high pressure COPV tank that weights an other of magnitude more than the fuel it contains. To generate electricity you need a bulky fuel cell with low efficiency, which in turn requires a very beefy cooling system, larger t…

A COPV has about 6% hydrogen by mass. At 33.3 kWh/kg, that’s ~2000 Wh/kg. This is far beyond the theoretical limits of li-ion batteries. Platinum is not a critical component, only necessary in current PEM fuel cells. Future fuel cells should eventually do away with platinum altogether. As hydrogen is effectively limitless too this is never going to be a resource concern.

A typical Mirai fuel consumption is 0.76kg/100km in similar driving conditions with a Tesla doing 15kWh/100km, so real world fuel density is 20kWh/kg - with a corresponding decrease in COPV density. You would then almost halve that density to take into consideration the whole electricity generating system, cell + cooling + the supercap or NiMH assembly that handle transients and regen braking etc.

So the density advantage of Hydrogen is limited, half to a third the battery mass with comparable volume. Not a game changer in 2010, and certainly not now, when everything else is against it.

The much improved and high performance fuel cells have been just around the corner for two decades. In the meantime, BEV sales have outstripped H2EVs one thousand to one, growing exponentially every year. How could anyone even consider buying a H2EV when the reliability of infrastructure is a joke even in the most mature US market [1]? Considering electric chargers are becoming ubiquitous and anyone can install one in their own home?

I think one needs to smell the roses, it's not a festive occasion for H2EVs.

[1] https://www.motortrend.com/reviews/2021-toyota-mirai-long-te...

Re: EU drafts plan to label gas and nuclear investments as green

#440
post #439
post #436

Earlier quoted context omitted.

A COPV has about 6% hydrogen by mass. At 33.3 kWh/kg, that’s ~2000 Wh/kg. This is far beyond the theoretical limits of li-ion batteries. Platinum is not a critical component, only necessary in current PEM fuel cells. Future fuel cells should eventually do away with platinum altogether. As hydrogen is effectively limitless too this is never going to be a resource concern.

A typical Mirai fuel consumption is 0.76kg/100km in similar driving conditions with a Tesla doing 15kWh/100km, so real world fuel density is 20kWh/kg - with a corresponding decrease in COPV density. You would then almost halve that density to take into consideration the whole electricity generating system, cell + cooling + the supercap or NiMH assembly that handle transients and regen braking etc. So the density adva…

Which is still something like 1200 Wh/kg. Worlds beyond li-ion...
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