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Re:Tech Won’t Save Us. Shrinking Consumption Will by ramraj07 on Tuesday December 28, 2021 @10:23PM (#29721439)
It is true electryifying everything and going green on the grid is important, but do you think that when there’s oil available, no one’s going to use it? You can put laws in the big countries but what about the shady ones?
Re:Tech Won’t Save Us. Shrinking Consumption Will by Retric on Tuesday December 28, 2021 @11:00PM (#29721679)
As Oil loses economies of scale it’s only going to get more expensive not less. Meanwhile batteries, solar, and wind just keep getting cheaper. Future EV sales are going to come down to technology not subsides.

Also biofuels aren’t significant at current consumption levels, but could become so if we get close to net zero emissions.

Re:Tech Won’t Save Us. Shrinking Consumption Will by lambdadmitry on Tuesday December 28, 2021 @11:58PM (#29722054)
It's a really, really bad idea to extrapolate price reductions in solar/wind into carbon free grids. Unfortunately there's a ridiculous wall of increasing overprovision required as you go deeper and deeper into renewables. Have a look at [0] if you can make the paper fall from the back of a truck, especially at Fig. 3. Assuming absolutely perfect grid able to transmit arbitrary amount of electricity and disregarding any real constraints, going purely by geophysical constraints on the amount of wind and sun available, continental US would need at least x7 as much wind+solar capacity as it does consume on average to have no more than one day of blackouts per year, assuming 12hrs of full consumption stored and immediately dispatchable. The only scenario in which that number goes to about x1 requires 32 days of full storage, which is just impossible with our current tech. And as you can imagine, in any real scenario that number would need to be several times higher. It's an absolutely ridiculous cost barrier that is not talked about enough and that effectively guarantees that we will be burning fossils for the foreseeable future.

[0]: https://pubs.rsc.org/en/content/articlelanding/2018/ee/c7ee0...

Re:Tech Won’t Save Us. Shrinking Consumption Will by Retric on Wednesday December 29, 2021 @07:33AM (#29724234)
Those numbers are wildly off because among other things the use US generates 6% hydroelectric, and they didn’t try to minimize a cost function via location selection etc. Further large hydroelectric dams store months worth of their average output.

Also, demand and generation are positively correlated as people use less power on cloudy days and less AC in the winter. You can look at how much oversupply and storage people need to live off grid and realize that’s a worst case situation isn’t 7x oversupply or 30 days of storage it’s roughly 3x oversupply of solar and 3 days of storage. At grid scale that’s roughly 6c/kWh for solar plus batteries which last longer the less their used though that’s also a high when you add other energy sources and grid transmission.

The good news is markets are great at minimizing cost functions. In the near term lots of natural gas makes up the difference, but the cost breakdown is such that offsetting 1kWh of natural gas works out even if 50% of solar generation is wasted. Aka 2x oversupply of solar shows up from market forces it’s that cheap. Bring on storage and things start to look very solar heavy even with zero subsidy or price reductions.

Re:Tech Won’t Save Us. Shrinking Consumption Will by lambdadmitry on Wednesday December 29, 2021 @10:22AM (#29725584)
Hydroelectric can't ramp up to a large fraction of national demand, for multiple unsurmountable reasons (like, you can't dump the water fast enough for one). Location selection doesn't matter that much as they don't try to optimise cost, they just look at aggregate output.

People living off grid still continue to consume the products of grid-enabled industries, from manufacturing to farming to logistics to infrastructure. Heating/cooling and lighting a cabin is much more trivial than paving a road coming to that cabin, feeding its inhabitants, building solar panels for them, or ensuring dense enough population to make research and manufacturing viable. In fact, we don't need to extrapolate minor part of personal consumption to the whole society, we have aggregate energy consumption numbers.

"Market forces" can't generate electricity on their own. Instead of taking the bottom-up view, fraught with wishful thinking and unstated assumptions, why not take the top down, working from the potential generation capacity under ideal assumptions? That's exactly what the paper I linked did, and the results are… not great for 100% renewable

Re:Tech Won’t Save Us. Shrinking Consumption Will by Retric on Wednesday December 29, 2021 @10:39AM (#29725759)
> can’t ramp up

6% is already a large fraction of grid demand and that’s an average. It’s critical for finding anything that’s even vaguely accurate.

“Why no take the top down” because we want to minimize costs. It doesn’t matter how much over production happens vs how much energy storage happens, what matters is how much each costs.

If you really want to do a high level analysis you need to cover a wide range of major inputs. Hydro flexibility and the costs to increase that flexibility, as in how much can it ramp up and how much can it average over a year. Next is the actual cost of Wind in each location for various turbines and the time of day for production this varies quite a bit and becomes a massive optimization problem. Next is solar production at each location as well as how panels are aimed in various wealthier conditions, again a major optimization problem. Next actual energy output vs demand, Aka actually modeling what happens to both for various weather events. Next is cost of grid storage capacity, as in how much capital needs to sit around. Next is how much to utilize grid storage as in a charge vs discharge cycle, the first vs second are different for each technology and a mix of several is likely. Next grid interconnect costs as in how much does flexibility cost both in dollars and resistive losses. Next optimized Solar and wind capacity vs grid demand as in at each set of seasonal and weather conditions to minimize costs. Finally changes to costs over time or based on deployment.

It’s possible to model all of that, but in turns out that’s what markets do. The bottom up approach isn’t wishful thinking it’s what actually happens as people build A due to A being profitable up to point X when building B is more profitable etc etc.

Re:Tech Won’t Save Us. Shrinking Consumption Will by bryanlarsen on Wednesday December 29, 2021 @08:49AM (#29724746)
The book I linked includes a realistic model incorporating existing hydro, significant rooftop solar, et cetera. It requires a 20% overbuild.

https://mitpress.mit.edu/books/electrify

Re:Tech Won’t Save Us. Shrinking Consumption Will by lambdadmitry on Wednesday December 29, 2021 @10:26AM (#29725644)
Hydroelectricity is very limited in its maximum instantaneous output, you can't feed half a grid with it, there is just nowhere to put all that water to without massive flooding, so it's a bit of a moot point. Rooftop solar doesn't matter for the top down approach in that paper, they don't make any assumptions about PV location and assume perfect grid, so rooftop PV won't make it any better. So seeing a top down, intentionally optimistic approach arriving at a number much higher than that book's author's, I am very sceptical of the book's results.
Re:Tech Won’t Save Us. Shrinking Consumption Will by liketochill on Wednesday December 29, 2021 @03:42AM (#29723069)
Not sure why you are downvoted you have a valid point with regards to over provisioning and storage.

I wonder how much dispatchable generation has to be kept around to only have two 12 hour blackouts per year due to lack of generation.

Re:Tech Won’t Save Us. Shrinking Consumption Will by bryanlarsen on Wednesday December 29, 2021 @08:48AM (#29724738)
3 hours, some overbuilding and a good grid to get to 99.99% reliability (under an hour of blackouts).

https://www.nature.com/articles/s41467-021-26355-z

Re:Tech Won’t Save Us. Shrinking Consumption Will by lambdadmitry on Wednesday December 29, 2021 @10:10AM (#29725445)
I don't see where that number comes from.

Also, "good grid" means "perfect national transmission", which is a wildly optimistic assumption. The US is currently split into multiple grids, with ties being able to handle less than 1% of their generation capacity.

Moreover, that's just the US. Here is what the link has to say about countries less blessed with landmass and latitude:

> Indeed, in smaller countries, substantial gaps (>30% of demand for >20 h per year; pale orange curves in Fig. 4) remain in systems even with 12 h of energy storage and annual generation that is 3x annual demand.

Or this, directly referring to extensive overbuilding required to meet demand:

> For instance, historical solar and wind resources data in Germany reveal that there were nearly 2 weeks in which dispatchable generation had to cover practically all of the demand because of a period with very low solar and wind power availability (called “dark doldrums”)27. Although with vast enough wind and solar capacity it might still be possible to meet demand in all hours, the required capacity increases exponentially after a point that depends on the renewable resources of that country, and it is this geophysically-dependent point that will largely determine the cost-effectiveness of highly-reliable, renewables-based electricity systems.

Re:Tech Won’t Save Us. Shrinking Consumption Will by bryanlarsen on Tuesday December 28, 2021 @10:28PM (#29721477)
AFAIK, there is only a single country that isn't part of the global economy and thus isn't vulnerable to sanctions, and North Korea doesn't have any oil.

Carbon tariffs are one of those brilliantly awesome ideas that would solve a lot of issues like these.

Re:Tech Won’t Save Us. Shrinking Consumption Will by fogihujy on Wednesday December 29, 2021 @03:16AM (#29722947)
They still use, and export coal though.
Re:Tech Won’t Save Us. Shrinking Consumption Will by Schiendelman on Tuesday December 28, 2021 @10:28PM (#29721483)
Great point! We replied at the same time and I think we’re thinking the same way. :)
Re:Tech Won’t Save Us. Shrinking Consumption Will by Schiendelman on Tuesday December 28, 2021 @10:28PM (#29721479)
Once the big countries seriously start to transition, they’ll need the shady countries to stop benefiting from oil as well. We’ll all end up paying poor countries to not use oil, and embargoing them if they keep it up - and that’ll be a worthy thing to pay for.
Re:Tech Won’t Save Us. Shrinking Consumption Will by actually_a_dog on Tuesday December 28, 2021 @11:21PM (#29721817)
I've got one word for you: China.

The US can't just cut off China without serious second order effects rippling through the economy. Therefore, it won't happen. And, if you can't get China to cooperate, none of it matters. They're currently the largest emitter of greenhouse gasses, have publicly said they'll be increasing their emissions for some time, and have not committed to net zero before 2060.

Re:Tech Won’t Save Us. Shrinking Consumption Will by Stupulous on Wednesday December 29, 2021 @12:23AM (#29722181)
China's emissions per capita are half that of the US, and it seems very reasonable that they would see an increase in carbon emissions as the average standard of living goes up. The US is only aiming for carbon neutral by 2050, and we have less work to do and more money to do it with. I'm no fan of China, but I think we're on the same page regarding renewables.
Re:Tech Won’t Save Us. Shrinking Consumption Will by actually_a_dog on Wednesday December 29, 2021 @12:29AM (#29722217)
That's all well and good, but your real problem is that both of those pages fall well after the book is closed on being able to make a real difference. I also forgot to note that India has only committed to net zero emissions by 2070, and that's far too late to avoid serious issues.
Re:Tech Won’t Save Us. Shrinking Consumption Will by lambdadmitry on Thursday December 30, 2021 @07:14AM (#29736098)
Per capita emissions don't matter for the atmosphere, aggregate emissions do. Yes this makes big population a liability, but it is what it is.
Re:Tech Won’t Save Us. Shrinking Consumption Will by Stupulous on Friday December 31, 2021 @01:27AM (#29745556)
They matter if we're asking whether China is on the US' side on this.

China's people shouldn't be forced to live in worse conditions because they live in more populous nation. You could split China into two countries with US-level emissions, and we'd be in exactly the same place globally.

Re:Tech Won’t Save Us. Shrinking Consumption Will by lambdadmitry on Saturday January 01, 2022 @01:22PM (#29761053)
> China's people shouldn't be forced to live in worse conditions because they live in more populous nation

According to the logic of degrowth, they should be forced to live in conditions that allow for net zero total emissions of the country they live in. If anything, it should be easier for them because they're a unitary dictatorship, so can degrow by edict. I can't see how not focusing on China in that regard can make sense, they're emitting more currently, they are rapidly increasing their emissions (unlike the US), and they have a great potential to increase it much higher because they have lots more people. Therefore any degrowth strategy should be first and foremost applied to curb their emissions, yet somehow the conversation is always derailed into useless per-capita emissions that do nothing to the planet.

Re:Tech Won’t Save Us. Shrinking Consumption Will by josephcsible on Saturday January 01, 2022 @01:53PM (#29761360)
> You could split China into two countries with US-level emissions

Well first of all, two wouldn't suffice. It's at least three, and I think it might even be four. And with a bunch of mini-Chinas, there'd be more competition for where manufacturing happens, and it could drive emissions down the same way that breaking up a monopoly drives price down.

Re:Tech Won’t Save Us. Shrinking Consumption Will by Stupulous on Sunday January 02, 2022 @12:12AM (#29766040)
By Wikipedia's 2019 numbers (14 Gt China/6.6 Gt US) you'd need 2.12 mini-Chinas.
Re:Tech Won’t Save Us. Shrinking Consumption Will by josephcsible on Sunday January 02, 2022 @03:18PM (#29773319)
The article I was remembering was https://www.bbc.com/news/world-asia-57018837 in which case the result of the division is 2.45. But in any case, since you can't have a fraction of a country in this context, you would indeed need 3 for each one to have lower emissions than the US.