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Majority of America's underground water stores are drying up, study finds

thehill.com

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Re: Majority of America's underground water stores are drying up, study finds

#181

Earlier quoted context omitted.

At the point my solar panel is installed all the death is built in. At the point my coal plant explodes, all the death is built in (no more outgassing, health increases going forward in fact). The problem with the death toll of nuclear is that it's deferred.... So no one can agree what the impact of Chernobyl is. For instance, the UN cites a report and claims 4000 dead post accident. The report itself says 9000. Gree…

As a pro solar pragmatic engineer response: > At the point my solar panel is installed all the death is built in. No. The toxic waste ponds left after creating your solar panels remain with all the carcinogenic after effects. The large volume of low level radiactive waste from lithium processing for batery banks remains in ponds (again, see Lynas, Malaysia) awaiting possible pond leakages. > no one can agree what the…

> The toxic waste ponds left after creating your solar panels remain

Yes we're bad at cleaning things up AT SCALE. We do stupid and shitty things to make a buck AT SCALE. People are terrible...

>> Chernobyl, lessons were learned from Fukishima (which had fewer deaths than the earthquake events and fewer deaths than serious mining accidents).

https://www.insurancejournal.com/news/international/2017/11/...

Disasters at power plants are dangerous. There is a coal plant whose explosion killed about the same number of people who died on site at chernoble.

That toxic pond left over from solar. No one looks at it, no one gives a fuck about it, and though we know how to clean it up we dont. The clean up from Fukushima, from Chernobyl is at present close to 100 billon, and will continue for 1000's of years. The the melted down fuel on both sites will remain in place for a long time to come. ( https://apnews.com/article/japan-nuclear-fukushima-plant-dec... )

Thats 860 tons of nuclear waste at Fukushima that we dont know what to do with.

There is also the off site storage, that cotiains rubble removed from site, and the spent fuel from ponds on site.

All of this material remains a threat, it will have to remain tagged, tracked and under guard for the rest of its life. OR get dug up, buried and hidden away in so deep that we hope no one finds it.

> By how much though? Designs have changed since Chernobyl, lessons were learned from Fukishima ... There are risks everywhere - it's difficult for many to pragmatic assess and compare risk.

The risks from nuclear are so high that everything gets tagged, tracked, checked on by national and international agencies, and remains under guard. Nulcears toxic pond is going to last for 1000's of years, longer than any human civilization has. It's going to need to be tracked, tagged and guarded for that time or it will become an existential threat all over again (dirty bomb any one). All the toxic ponds are over and forgotten and nuclear is rearing its ugly head, is costing us still.

We know the risks for solar, we know the risks for nuclear. There is a reason no one is building more at scale. There is a reason we only built one (comerical) reactor in 40 years in the us. The economics of them dont make sense (no one wants 1000 years of liablity) . The one we did just build (new site, not adding to an existing one) is a whole story in and of itself, money the DOE and the DOD are all involved in that (and the potential for producing tritium in the us again).

Re: Majority of America's underground water stores are drying up, study finds

#182

> To an outsized extent, the problems identified in the Nature study are — for Americans at least — problems of California, and of the national food systems’ reliance on the fertile Sacramento and San Joaquin valleys and the groundwater beneath. This makes it sound like the only sane option is for the rest of the USA to stop being so dependent on California.

One change which would have to be made is here in the Midwest, we grow a lot of soybeans and corn. We feed most of it to animals. There are likely better uses for that land, especially when talking about modern corn as it is so nitrogen hungry that nearly all farmers apply high nitrogen fertilizer...which runs off into the rivers and causes the dead zone in the Gulf of Mexico. So, so many things could be better if we…

Plants are already pretty inefficient (~1-3%) at converting solar energy to stored chemical energy (glucose -> fats/carbs)

https://www.ars.usda.gov/news-events/news/research-news/2012...

However ignore the solar conversion, we put in a ratio of 3:1 i.e 3 calories of energy in for 1 calorie of energy out in plant energy (30%).

https://sustainability.emory.edu/wp-content/uploads/2018/02/...

Add the mix of energy required for irrigation, producing industrial fertilizers, harvesting and then feeding to another inefficient organism (cows, pigs, chicken).

https://cbey.yale.edu/our-stories/disrupting-meat

Cows are 25:1 ratio (4%) calories of feed in to calories of meat out. Pigs are 1:15 (6%), and Chicken is 1:9 (11%).

So if you take the total amount of energy received from sun being converted to chemical energy in cows that is only 0.012% of solar energy output into beef.

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The biggest breakthrough we can make as humans is to efficiently convert solar energy into chemical energy. chemical energy we can eat as food for humans that tastes great, and chemical energy we can use for homes, transport and industrial processes.

And the thing about converting solar -> chemical energy is that it is carbon negative. Plants and phytoplankton are 1% efficient, yet they convert billions of tons of C02 + solar energy into chemical energy.

https://earthobservatory.nasa.gov/features/Phytoplankton

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I'm hoping in our lifetimes we can crack artificial high efficiency photosynthesis at scale with engineered algae.

Oil is only cheap because of 10s of 1000s of years it has been compacted underground, but at our rate, we may deplete it in 100-200 years.

Engineered algae would be way cheaper and distributed than oil. Most humans live where there is sunshine and water.

Our future depends on how efficiently and cheaply we can convert solar -> chemical energy.

Re: Majority of America's underground water stores are drying up, study finds

#183

Earlier quoted context omitted.

O&G won because the energy density is so extremely high.

Gasoline may be a lot more energy dense, but ICE are about 20% to 40% efficiency while electric motors are about 60% - 80% efficient. So the differences aren't as great as you might think. If we hadn't just jumped at gasoline and money hadn't flowed so readily towards that tech, there's no telling how far battery tech would be today. A lot further than it is now, I have no doubt. The fact is that big oil has killed o…

> Gasoline may be a lot more energy dense, but ICE are about 20% to 40% efficiency while electric motors are about 60% - 80% efficient.

You are correct about energy efficiency of ICE vs electric motor efficiency.

> So the differences aren't as great as you might think.

https://en.wikipedia.org/wiki/Energy_density

  +-----------------------------+-------------+------------------+-------------------+
  |              *              |  Gasoline   | Li-ion Batteries | Gasoline Multiple |
  +-----------------------------+-------------+------------------+-------------------+
  | Gravimetric Density (MJ/kg) | 0.59 – 1.06 |             46.4 | 56.5x             |
  | Volumetric Density (MJ/L)   | 1.74 – 2.83 |             34.2 | 15.5x             |
  +-----------------------------+-------------+------------------+-------------------+
Gasoline weighs ~50x less and takes 15x less volume for the same energy in a battery.

There is only so much electrical energy that can be jammed in metals that form batteries. Chemical energy in C-C or C-H bonds is so much more dense.

https://chem.libretexts.org/Bookshelves/Physical_and_Theoret...

In a similar paradigm, fusion energy is 20-100 million times more dense than gasoline.

https://climate.mit.edu/explainers/fusion-energy

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We have so much science and engineering to do to truly be masters of energy and intelligence.

Re: Majority of America's underground water stores are drying up, study finds

#184
post #51

Earlier quoted context omitted.

there are ~90M cattle in the US, so more than before ?

Wonder much the average buffalo consumes vs the average cow? It's probably relevant in order to provide some kind of scaling factor. :)

Probably more, considering they're likely similar mass but migrate more than cows do who are usually relatively confined

Re: Majority of America's underground water stores are drying up, study finds

#185
post #182

Earlier quoted context omitted.

One change which would have to be made is here in the Midwest, we grow a lot of soybeans and corn. We feed most of it to animals. There are likely better uses for that land, especially when talking about modern corn as it is so nitrogen hungry that nearly all farmers apply high nitrogen fertilizer...which runs off into the rivers and causes the dead zone in the Gulf of Mexico. So, so many things could be better if we…

Plants are already pretty inefficient (~1-3%) at converting solar energy to stored chemical energy (glucose -> fats/carbs) https://www.ars.usda.gov/news-events/news/research-news/2012... However ignore the solar conversion, we put in a ratio of 3:1 i.e 3 calories of energy in for 1 calorie of energy out in plant energy (30%). https://sustainability.emory.edu/wp-content/uploads/2018/02/... Add the mix of energy requir…

The hyper-efficient algae you describe sounds a bit like ice-9…

Re: Majority of America's underground water stores are drying up, study finds

#186
post #182

Earlier quoted context omitted.

One change which would have to be made is here in the Midwest, we grow a lot of soybeans and corn. We feed most of it to animals. There are likely better uses for that land, especially when talking about modern corn as it is so nitrogen hungry that nearly all farmers apply high nitrogen fertilizer...which runs off into the rivers and causes the dead zone in the Gulf of Mexico. So, so many things could be better if we…

Plants are already pretty inefficient (~1-3%) at converting solar energy to stored chemical energy (glucose -> fats/carbs) https://www.ars.usda.gov/news-events/news/research-news/2012... However ignore the solar conversion, we put in a ratio of 3:1 i.e 3 calories of energy in for 1 calorie of energy out in plant energy (30%). https://sustainability.emory.edu/wp-content/uploads/2018/02/... Add the mix of energy requir…

I think you're optimizing the wrong thing here. We don't need to be hyper efficient in terms of Sun's energy, as it's one of the most abundant sources of energy available and will not run out any time soon.

First one should optimize over land and resource use, as well as sustainability (CO2, fertilizer run-off etc.). Not to mention cost (including subsidies).

Re: Majority of America's underground water stores are drying up, study finds

#187

Earlier quoted context omitted.

The main point they are trying to make is the people eating most of the beef are dying off. If the trend holds and younger generations don't drastically increase beef consumption, there just won't be anyone to eat the same amount of beef they are producing currently. Therefore, they will have to reduce beef production which may reduce water used when growing food to feed the cattle as fewer cattle eat less food. So t…

But what does all that have to do with anything? It won't resolve itself. Natural products have ebbs and flows. Meat isn't exactly a luxury product.

The way we produce meat is anything but natural these days. That takes its toll on our resources. Far more than growing food directly for humans does.

Re: Majority of America's underground water stores are drying up, study finds

#188

Earlier quoted context omitted.

One change which would have to be made is here in the Midwest, we grow a lot of soybeans and corn. We feed most of it to animals. There are likely better uses for that land, especially when talking about modern corn as it is so nitrogen hungry that nearly all farmers apply high nitrogen fertilizer...which runs off into the rivers and causes the dead zone in the Gulf of Mexico. So, so many things could be better if we…

A lot of that corn goes into ethanol instead.

Roughly 1/3rd of the US corn production is for ethanol[1], 1/3rd for animal feed, and 1/3rd for human food products. Ethanol kind of sucks as a fuel though, because it can't be piped for various reasons[2] including water-induced separation in gasoline-ethanol blends and oxygen induced steel corrosion requiring specialized pipeline construction to mitigate. This means ethanol is usually shipped via train and worse, trucked, increasing diesel usage/emissions on top of the farm equipment emissions to grow and harvest the corn in the first place.

So in the end it isn't much better than pure gasoline at best, and is actually overall higher total emissions at worst.

Edit: ethanol also doesn't have the same range as gasoline per tank, so vehicles may need to fuel up more often, making the problem worse.

1. https://www.usda.gov/media/blog/2019/07/29/corn-americas-lar...

2. https://www.ogj.com/refining-processing/article/17217746/eth...

Re: Majority of America's underground water stores are drying up, study finds

#189

Earlier quoted context omitted.

they're testing some new tech that directly uses the sun to desalinate. Really, what's required for the electric grid is ways to store the energy, and not use it. For places like Arizona, they may need a whole different type of infrastructure of grey water use. Just piping in water ain't gonna be sustainable.

Water is a lot easier to store than electricity. Desalinate while the sun is shining to fill a reservoir that you can pull from 24/7.

Pumped storage hydro is a way to store energy, but also can dispense water.

Re: Majority of America's underground water stores are drying up, study finds

#190
post #101

Earlier quoted context omitted.

The failures of a tiny player like Tesla Solar are totally unrelated to US solar photovoltaic (PV) capacity. From 2021 to 2022 solar PV went from ~161,499 GWh to ~202,080 GWh of net generation (~25.1% increase) [1]. Utility scale went from 112,335 GWh to 140,798 GWh (~25.3% increase) [2] and personal/small scale solar PV went from ~49,164 GWh to ~61,282 GWh (~24.6% increase). New solar PV accounts for 11,058 MW of th…

What is the cost of a $50,000 at 10% interest vs the cost of $50,000 at 2.5% interest over 10 years? Money is not free. Solar is now expensive: [1] https://www.cnet.com/home/energy-and-utilities/high-interest... [2] https://www.bloomberg.com/news/newsletters/2023-11-03/invest... [3] https://finance.yahoo.com/news/solar-stocks-get-hit-as-risin... [4] https://www.nytimes.com/2023/12/05/climate/renewable-energy-... [5]…

Utility-scale solar is what is both cheap and plummeting in price, relative to other sources, and has even gone negative during peak production hours.
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