[eclipse]

Seriously guys - the Isaac Arthur below is awesome! Here's the teaser headline to give a vibe of the humour:-


$this->bbcode_second_pass_quote('', 'C')ivilisation has collapsed. The only rational way forward is to cover your dune buggy with spikes, craft some leather, S&M armour, and resort to cannibalism. Mohawks are optional.
https://youtu.be/QWmEgu1iP_E

[theluckycountry]

$this->bbcode_second_pass_quote('eclipse', 'S')eriously guys - the Isaac Arthur below is awesome! Here's the teaser headline to give a vibe of the humour:-

[eclipse]

If we nuked ourselves today, in 100 years I personally think the population would be back to like 7 or 8 billion, and we'd have modern cities but without the car dependent suburbia (because there wouldn't be the easy oil to drive all that.) There's just so much we could scavenge so fast that we'd bounce back. Fast.

[Plantagenet]

$this->bbcode_second_pass_quote('eclipse', 'I')f we nuked ourselves today, in 100 years I personally think the population would be back to like 7 or 8 billion, and we'd have modern cities but without the car dependent suburbia (because there wouldn't be the easy oil to drive all that.) There's just so much we could scavenge so fast that we'd bounce back. Fast.

[eclipse]

The nuclear winter scientists are retracting their work.
Even a large nuclear war couldn't really touch the likes of Mt Pinotubo.
https://youtu.be/KzpIsjgapAk

[Plantagenet]

$this->bbcode_second_pass_quote('eclipse', 'T')he nuclear winter scientists are retracting their work.

[Plantagenet]

Oops...sorry. I read the discussion about nuclear winter in NATURE but I didn't put the link in my post above.

SOOOO....Here is the link to a recent (2020) discussion of nuclear winter, and the likelihood that it would occur after even a limited and small nuclear war.

NATURE: nuclear winter would occur after even a small nuclear war



Cheers!

[eclipse]

I suggest you watch the youtube I submitted - one of the original nuclear winter scientists retracting his work, and why.
Then I suggest you read the nuclear winter wiki and see how politicised this is.
The youtube shows how conflicting the politics is.
He HATES the idea of nuclear war.
But he also HATES bad science, which discredits all science in the popular mind when it is found to be wrong.
He is just trying to be honest.
He shows recent bushfire science shows that not enough soot gets high enough to stay for a while.
The Australian megafires of 2019 make it into his data.
I was here.
Sydney was brown.
It was horrendous.
I could barely breath for months - I felt like I had become a smoker.
But it wasn't really high enough to stay and lower temperatures.
And it was the most intense climate-driven megafires we have ever had - with rainforests that have not burned in MILLIONS of years drying out and burning.

[eclipse]

The theory is that smoke gets lofted high when large areas burn, right?
Hiroshima burned 6 square miles. The Australian 2019 bush fires burned 24,324 square miles - 4054 times bigger area.
But they only cooled the planet about 0.06 ± 0.04 K by mid-2020.
https://agupubs.onlinelibrary.wiley.com ... 21GL093841
Yet Mt Pinotubo threw millions of tons of sulfur dust up past the rain into the stratosphere where it could last years, cooling the planet by a degree for a few years.
It's all about how high the smallest lightest particles can get - and the Aussie bushfires show that giant fires are not enough. Also, remember those bushfires often generated the pyrocumulous storms - bushfire lightning storms - that look like mushroom clouds.
But still no competition for one volcano.
So I know both cities and bombs are bigger today than Hiroshima, but are they a combined 4054 times bigger? And even if the area burned is larger - is the soot really going to go higher? That huge Aussie fire only cooled the planet .06 degrees!

[eclipse]

But enough of me - over to the peer-reviewed work.

The Toon vs Reisner teams are still debating this.

Toon was a contemporary of Sagan, and probably not keen to see any shift on the nuclear winter science.

But Reisner is more optimistic:

"We present a multiscale study examining the impact of a regional exchange of nuclear weapons on global climate. Our models investigate multiple phases of the effects of nuclear weapons usage, including growth and rise of the nuclear fireball, ignition and spread of the induced firestorm, and comprehensive Earth system modeling of the oceans, land, ice, and atmosphere. This study follows from the scenario originally envisioned by Robock, Oman, Stenchikov, et al. (2007, https://doi.org/10.5194/acp-7-2003-2007), based on the analysis of Toon et al. (2007, https://doi.org/10.5194/acp-7-1973-2007), which assumes a regional exchange between India and Pakistan of fifty 15 kt weapons detonated by each side. We expand this scenario by modeling the processes that lead to production of black carbon, in order to refine the black carbon forcing estimates of these previous studies. When the Earth system model is initiated with 5 × 109 kg of black carbon in the upper troposphere (approximately from 9 to 13 km), the impact on climate variables such as global temperature and precipitation in our simulations is similar to that predicted by previously published work. However, while our thorough simulations of the firestorm produce about 3.7 × 109 kg of black carbon, we find that the vast majority of the black carbon never reaches an altitude above weather systems (approximately 12 km). Therefore, our Earth system model simulations conducted with model-informed atmospheric distributions of black carbon produce significantly lower global climatic impacts than assessed in prior studies, as the carbon at lower altitudes is more quickly removed from the atmosphere. In addition, our model ensembles indicate that statistically significant effects on global surface temperatures are limited to the first 5 years and are much smaller in magnitude than those shown in earlier works. None of the simulations produced a nuclear winter effect. We find that the effects on global surface temperatures are not uniform and are concentrated primarily around the highest arctic latitudes, dramatically reducing the global impact on human health and agriculture compared with that reported by earlier studies. Our analysis demonstrates that the probability of significant global cooling from a limited exchange scenario as envisioned in previous studies is highly unlikely, a conclusion supported by examination of natural analogs, such as large forest fires and volcanic eruptions."
https://agupubs.onlinelibrary.wiley.com ... 17JD027331

[C8]

I cannot imagine anyone can predict how a nuclear mass bombing would affect the climate. There are way too many variables and things about the Earth's ecosystem that we still do not understand.

I also think that models will not affect the risk taking nature of nations- so it really doesn't matter.

[vtsnowedin]

$this->bbcode_second_pass_quote('C8', 'I') cannot imagine anyone can predict how a nuclear mass bombing would affect the climate. There are way too many variables and things about the Earth's ecosystem that we still do not understand.

I also think that models will not affect the risk taking nature of nations- so it really doesn't matter.

[eclipse]

Hear hear! Let's not test this theory out!

Also, I'm reconsidering what I thought I 'knew'. My youtube source above is not what I thought it was, and the peer-reviewed debate is still in a back and forth between various climate models from experts on both sides. If peer-review have not sorted this out yet, who am I to take a side?

Now back to the thread topic.

What is the critical limit or challenge for an all renewable grid? (Of course meaning wind and solar - geothermal, hydro and others are already fairly maxed out.) Do you guys use the term VRE for "Variable Renewable Energy"?

I'm not saying I'm completely sold that solar and wind can do a 100% renewable grid - but I'm more open to it. (I'm still a fan of nukes.)

What is changing my mind is the the fact that wind and solar are now SO cheap you can overbuild them for winter. If you're good for winter with all that overbuild, then storage is less of an issue. Vox discusses a study which says storage costs could go as high as $150 / kwh installed capacity cost and still be economic because you're using so little of it. ($150 also requires a few smart-grid tricks like demand-shifting flexible stuff like industrial cooling processes etc.)

https://www.vox.com/energy-and-environm ... lectricity

The summer excess can desalinate water in desert countries or be stored as heat for colder climates that might need local heat. Heat? What could store heat that long? Now we're getting into what blew my mind.

Imagine a giant warehouse - bigger than your local hardwarehouse - full of hot graphite-blocks heated by 2000 degree molten metal tin pumped through the system. The heat is trapped in argon gas. Apparently these can store heat for months.

Half the genius of this system was inventing pumps that wouldn't melt at 2000 degrees! See:-
"Liquid Metal Research Paper - Royal Chemistry Society"
https://pubs.rsc.org/en/content/article ... c8ee02341g

Not only that, they could hypothetically pump the heat out to run a turbine to get the electricity back. BUT THEY DON'T! Instead they dip something like a photovoltaic cell in, but it's a Thermo-Photovoltaic units. Yeah, I'm with you. I also thought it would just melt! But these things come with cooling systems.

The whole thing is covered in this next youtube video - but what's better is that MIT estimate it could come in at $10 / kwh capacity capital cost. This is so cheap it might allow a relatively 'normal' grid even with intermittent renewables!

https://youtu.be/Gn7pfYKB7DA

Thermophotovoltaic efficiency of 40%
https://www.nature.com/articles/s41586-022-04473-y.pdf

"Near-perfect photon utilization in an air-bridge thermophotovoltaic cell"
https://www.nature.com/articles/s41586-020-2717-7.epdf

[Tanada]

$this->bbcode_second_pass_quote('eclipse', '[')b]What is the critical limit or challenge for an all renewable grid? (Of course meaning wind and solar - geothermal, hydro and others are already fairly maxed out.) Do you guys use the term VRE for "Variable Renewable Energy"?

I'm not saying I'm completely sold that solar and wind can do a 100% renewable grid - but I'm more open to it. (I'm still a fan of nukes.)

What is changing my mind is the the fact that wind and solar are now SO cheap you can overbuild them for winter. If you're good for winter with all that overbuild, then storage is less of an issue. Vox discusses a study which says storage costs could go as high as $150 / kwh installed capacity cost and still be economic because you're using so little of it. ($150 also requires a few smart-grid tricks like demand-shifting flexible stuff like industrial cooling processes etc.)

[C8]

$this->bbcode_second_pass_quote('eclipse', '
')What is changing my mind is the the fact that wind and solar are now SO cheap

[vtsnowedin]

$this->bbcode_second_pass_quote('C8', '')$this->bbcode_second_pass_quote('eclipse', '
')What is changing my mind is the the fact that wind and solar are now SO cheap

[kublikhan]

$this->bbcode_second_pass_quote('', '*') European Commission could move to put lithium on a list of toxic substances.
* This piece of regulation could drive up prices across the battery supply chain.
* Should the European Commission take this decision, it may undermine the EU’s energy security.

A potential European Commission (EC) act to classify lithium as a Category 1A reproductive toxin in this year’s fourth quarter could undermine the European Union (EU)’s attempt to create and support a domestic battery materials supply chain. The EU currently relies heavily on imports of lithium to supply its nascent electric vehicle (EV) production sector and the classification may increase its reliance on other regions, at a time when the union is focused on energy security and reducing emissions. The European Chemicals Agency (ECHA)’s Risk Assessment Committee (RAC) at the end of 2021 published its opinion that it agreed with French proposals to classify three lithium salts as Category 1A reproductive toxicants.

“The EU is a global regulatory powerhouse, so any decision to classify lithium as Category 1A toxicant in the world’s largest single market will be keenly studied by regulators elsewhere. Industry hates regulatory uncertainty, so the longer it takes for a ruling, the more it will delay existing and significant investment decisions. This is more than a technicality; the impact could be far-ranging and wide.”

Implications for EV production
A drawn-out permitting process for new mining operations in Europe has already been highlighted at recent industry events as one of the main barriers to new mining projects ramping up quickly. Rystad Energy is aware of at least one new proposed lithium hydroxide processing operation that is now withholding its investment decision pending the outcome of the EC’s final resolution.

[kublikhan]

$this->bbcode_second_pass_quote('C8', 'B')ut is that b/c of govt. subsidies? If so, then it won't scale up well worldwide

[Newfie]

Lithium batteries, especially some types, seem to be getting negative attention from insurance companies. Pleasure boat fires have brought negative attention, some insurers won't insure boats with them.

Then there was the car carrier which recently sunk, lithium batteries in the electric cars aboard were blamed.

If there is a bad fire in a confined parking lot that could bring more negative attention.

This is still a young industry, lots could appen.

[kublikhan]

I'm curious to see if Tesla's switch to the safer LFP batteries will reduce the number of fires for those models. Time will tell.

$this->bbcode_second_pass_quote('', 'T')esla might be making a switch in its battery chemistry to a type that is less susceptible to combustion after sustaining damage.

One of the most appealing things about LFP (lithium ferrous phosphate) versus the current NCA type is that the battery pack has a much lower risk of fire or explosion, even when damaged in a collision. LFP batteries are known to have less energy density than the current NCA type, which might be seen as a drawback, however, the standard range models have enough room to use a larger battery pack and that might be the solution.

LFP also costs less and has a longer life, withstanding many more charge/discharge cycles than NCA. For safety-conscious shoppers, an LFP battery pack is also less likely to catch fire.