News for hackers. Stuff that matters.
Re:Old salt mine is the first emission-free compressed air e... by hervature on Tuesday August 18, 2020 @06:03PM (#24204889)
You are aware that nuclear power is not considered renewable by the majority of people correct? That puts Ontario at less than 50% renewable.
Re:Old salt mine is the first emission-free compressed air e... by yabones on Tuesday August 18, 2020 @06:12PM (#24204960)
You're technically correct, and what I should have said was 'zero-carbon emitting sources' as was in the source.

But for practical purposes there is so much Uranium on this planet that we'll most likely never even use 1% of it. Especially when you factor in newer or experimental reactor designs such as fast breeder reactors [1] that can generate even more power and use waste materials from current systems.

So yes, it is technically not a renewable source of energy, but there is such abundance of fuel that it's not 'non-renewable' the way Coal or Gas is.

[1] https://en.wikipedia.org/wiki/Breeder_reactor#Fast_breeder_r...

Re:Old salt mine is the first emission-free compressed air e... by IfOnlyYouKnew on Wednesday August 19, 2020 @04:26AM (#24208329)
If we're speaking of reality as opposed to theory, "renewables" was coined by environmentalists, and their exclusion of nuclear power has simply become part of the commonly-understood definition of term, except in the State of Utah.

And even though I get why one would believe that nuclear power should be included among Solar/Hydro/etc., it's slightly funny that proponents of nuclear power start start their pitch with "technically, nuclear is also..." when, technically, it clearly isn't.

Re:Old salt mine is the first emission-free compressed air e... by Akronymus on Wednesday August 19, 2020 @06:04AM (#24208799)
On top of that, we are VERY likely gonna get either fusion or space based mining within the time we have left before exhausting the "easily" reached uranium.
Re:Old salt mine is the first emission-free compressed air e... by pfdietz on Thursday August 20, 2020 @09:25AM (#24222954)
Fusion is very questionable -- it has inherently poor features from an engineering/cost point of view, and space is a terrible place to mine uranium or thorium. Earth is actually the best place in the solar system to mine uranium, as the element is concentrated by something like three orders of magnitude in the continental crust over average chondritic abundance.
Re:Old salt mine is the first emission-free compressed air e... by marmaduke on Wednesday August 19, 2020 @03:20AM (#24207994)
Aren’t waste disposal sites effectively non-renewable uses of natural space?
Re:Old salt mine is the first emission-free compressed air e... by ethanwillis on Wednesday August 19, 2020 @03:32AM (#24208057)
The amount of all nuclear waste ever produced takes up about the space of a football field.
Re:Old salt mine is the first emission-free compressed air e... by objclxt on Wednesday August 19, 2020 @04:30AM (#24208355)
> The amount of all nuclear waste ever produced takes up about the space of a football field

No.

Let’s be generous and use a soccer field, which is bigger than a NFL field, at 7,100 m3.

There is about 22,000 m3 of high level nuclear waste globally, according to the IAEA. That’s the really bad stuff. There’s 460,000 m3 of intermediate level (sludge, reactor cladding, etc), and 3,479,000 m3 of low level.

So yeah, considerably more than the space of a football field.

[source: https://nda.blog.gov.uk/2019/08/02/how-much-radioactive-wast...]

Re:Old salt mine is the first emission-free compressed air e... by daurnimator on Wednesday August 19, 2020 @04:40AM (#24208407)
How are you going from size of a field (which should be square meters) to volume (meters cubed)?

The MCG (an australian football field) is 25,000 square meters. The stadium holds approx 1,700,000 cubic metres.

"Football field" is a highly regional term.... lets not measure things in them?

Re:Old salt mine is the first emission-free compressed air e... by ethanwillis on Wednesday August 19, 2020 @05:41AM (#24208690)
Just a quick clarification. My comment wasn't clear I wanted to talk about waste from reactors specifically, but yes there is more nuclear waste if you do include all sources.

Why don't we talk about the difference between high level nuclear waste(HLW), intermediate level waste(ILW), and low level waste (LLW)?

The volume breakdown for nuclear waste is roughly LLW 90% ILW 7% HLW 3%

"Radioactivity" contribution breakdown is like so. LLW 1% ILW 4% HLW 95%

[1] https://www.world-nuclear.org/information-library/nuclear-fu...

Re:Old salt mine is the first emission-free compressed air e... by swebs on Wednesday August 19, 2020 @08:10AM (#24209577)
>7,100 m3

You mean 7,100 m2. 22,000 cubic meters would fit in there if you stacked it just over 3 meters high.

Re:Old salt mine is the first emission-free compressed air e... by kobbe on Wednesday August 19, 2020 @04:19AM (#24208293)
The same is true for solar that is not easily recyclable.
Re:Old salt mine is the first emission-free compressed air e... by pfdietz on Saturday August 22, 2020 @09:12AM (#24243898)
What part of solar is not easily recyclable? The glass? Oh noez, now the world is being polluted with silicates!
Re:Old salt mine is the first emission-free compressed air e... by seb314 on Wednesday August 19, 2020 @06:41AM (#24208973)
how would solar result in areas beeing uninhabitable for decades (or much longer?) after we stopped using them?
Re:Old salt mine is the first emission-free compressed air e... by rmason on Tuesday August 18, 2020 @10:32PM (#24206596)
Thorium 'the green nuke' powered plants produce 1/1000 as much waste as uranium powered ones. They're also virtually impossible to melt down though to be fair they're more expensive to build.

https://en.wikipedia.org/wiki/Thorium-based_nuclear_power

We already had thorium plants run by the TVA as late as the early seventies. Research would be needed to modernize those designs, money our government has refused to spend.

China, India and other countries have thorium research projects. The Netherlands just brought the first thorium powered plant online since the fifties.

https://www.extremetech.com/extreme/254692-new-molten-salt-t...

Re:Old salt mine is the first emission-free compressed air e... by dredmorbius on Wednesday August 19, 2020 @12:54AM (#24207237)
Thorium plants also have the unfortunate characteristic of not existing in deployable commercial form (and only very barely in experimental form).
Re:Old salt mine is the first emission-free compressed air e... by arcticbull on Wednesday August 19, 2020 @01:06AM (#24207307)
CANDU reactors support mixed Uranium and Thorium fuel.

"CANDU can also breed fuel from the more abundant thorium. This is being investigated by India to take advantage of its natural thorium reserves." [1]

[1] https://en.wikipedia.org/wiki/CANDU_reactor

Re:Old salt mine is the first emission-free compressed air e... by dredmorbius on Wednesday August 19, 2020 @01:10AM (#24207331)
Thanks, noted.
Re:Old salt mine is the first emission-free compressed air e... by arcticbull on Wednesday August 19, 2020 @01:17AM (#24207375)
I think the reason they don't go the Thorium route is that Uranium is just so abundant -- and so incredibly energy dense -- there's not a hugely compelling reason to switch to Thorium.
Re:Old salt mine is the first emission-free compressed air e... by pfdietz on Wednesday August 19, 2020 @08:23AM (#24209657)
Thorium reactors are breeders. The Th gets converted to 233U. But breeders of any kind are uneconomical.
Re:Old salt mine is the first emission-free compressed air e... by dredmorbius on Wednesday August 19, 2020 @12:24PM (#24212204)
Why is that?
Re:Old salt mine is the first emission-free compressed air e... by pfdietz on Wednesday August 19, 2020 @06:24PM (#24217481)
They require an extra separation step (removing newly bred material from spent fuel, or removing fission products from molten salt). This is more expensive than just doing nothing to the spent fuel.

In the past, the idea was that nuclear would be cheap, but would run into uranium supply constraints, so breeding would save money. But that's not how it turned out. Nuclear was expensive not because of fuel, but because of the cost of the power plants. Uranium prices remain low. Also, the move to gas centrifuges reduced the energy consumed in uranium enrichment by a factor of 50.

Re:Old salt mine is the first emission-free compressed air e... by dredmorbius on Wednesday August 19, 2020 @10:57PM (#24219404)
Thanks.

My understanding is that uranium supplies remain constrained --- fewer than two decades if supplying 100% of total global generation, say. Price doesn't tell you much about total resource stock.[1] That's based on terrestrial sources. Seawater U separation in theory would extend resources considerably, but remains unproven at scale.

Thorium, other disadvantages notwithstanding, is at least more plentiful.

I'll note I'm not generally a fan of nuclear, though don't rule out any contributory role.

________________________________

Notes:

1. I'd argue generally that nonrenewable natural resource pricing theory, dating to Ricardo, but especially Hotelling, is entirely flawed. Much of it under suspicious circumstances.

Re:Old salt mine is the first emission-free compressed air e... by pfdietz on Thursday August 20, 2020 @07:41AM (#24222205)
Yes, but the "supplying 100% of global generation" doesn't have any bearing on current reality.

Anyway, this argument for thorium isn't something customers would care much about. It's basically "thorium would not suck as much as uranium-fueled burner reactors do if uranium gets much more expensive" rather than "nuclear power is more attractive now if we use thorium". The customer response to "nuclear as currently implemented fails badly if uranium runs out" is going to be "use something other than nuclear".

Re:Old salt mine is the first emission-free compressed air e... by dredmorbius on Monday August 24, 2020 @03:38AM (#24258277)
Late response, my apologies.

At some point we've got to address the question of how much energy is supplied to how many people and for how long.

Population is expected to rise for at least another 30-80 years, to between 9 and 12 billions by most estimates. These may not see US levels of energy access, but most authors project per capita energy wealth roughly comparable to present day European levels, largely as electricity. This represents multiples of present generating capacity.[1]

And energy represented by virtually any nonrenewable stock, including most fissionanbles, is finite. That's before allowing for technical limitations, concerns, wastes, risks, or other impacts.

When the U.S. was first transitioning from wood to coal, roughly 1860--1880, then-known reserves were calculated as sufficient for at least one million years at then-present rates of consumption.[2] The problem, of course, is that rates of consumption increased somewhat, by a greater rate than those of new coal discoveries. I can remember in the 1970s National Geographic adverts assuring readers that America's coal reserves were good for another 1,000 years, already a thousandfold reduction from 100 years prior. Today official estimates tend to run 200--300 years, though pessimistic ones suggest scarcely a century.[3] That's roughly 10,000 times sorter than initially anticipated, thanks largely to the Jevons Paradox: low-cost goods and increased efficience stimulate demand.

And all this before acknowledging that we simple cannot burn much more of the stuff.

So, no, I don't buy that "supplying 100% of global generation doesn't have any bearing on current reality.", as even a small fraction of a growing number, most especially an exponentially growing one, remains a large number.

________________________________

Notes:

1. 1991 per capita use, 287.8 GJ US, 75.3 GJ world, 123.6 GJ Europe. bp Statistical Review of World Energy 2020, p. 11. At 123 GJ * 12 billions souls, total global energy demand would be 1,476 EJ, vs. 584 EJ consumed 2019, a 250% increase. Total 2019 electric generation was 27,005 TWh, or 97.2 EJ, 16.6% of total global energy consumption. That works out to 3.46 MWh/capita, or about 395 W continuous per person.

2. Henry Erni, Coal oil and petroleum: their origin, history, geology, and chemistry (1865), p. 14. https://archive.org/details/coaloilpetroleum00erni/page/14/m...

3. BP's 2020 report gives an R/P ratio, reseves vs. production, equivalent to years supply at present consumption, of 390 years. This is an increase, though almost entirely due to reduced extraction, down from 22.27 EJ in 2011 to 14.30 in 2019. Consumption has fallen by more.

Re:Old salt mine is the first emission-free compressed air e... by pfdietz on Monday August 24, 2020 @06:46AM (#24259344)
If we're talking about ultimate limits on Earth, solar is probably better than nuclear, just from direct thermal pollution. Solar causes a moderate increase in sunlight absorbed, but otherwise just moves solar energy around. If the albedo of the ground on which the solar modules were installed was less than the efficiency of the modules, there is no local heating, although the produced power gets degraded to heat eventually elsewhere as it is used. For every kWh of power produced, nuclear adds 3 kWh of heat to the biosphere (1 from the power produced, 2 from the waste heat of the reactor.)

(This is really a reflection of the difference between primary energy, which today is largely thermal, and delivered energy, which is largely work or chemical. The conversion to renewable energy will greatly reduce the importance of thermal energy conversion, and will not require a 1-1 replacement of today's primary energy use.)

It's not at all clear energy use will grow that much more. Lesser developed countries will use more, but in advanced countries energy use has plateaued. We are currently very far away from limits on solar energy imposed by shortage of sunlight. The Earth is hit by 100,00 TW of sunlight; global primary energy use is 20 TW.

If we're talking about limits OFF the Earth, solar is vastly more abundant than uranium (or, for that matter, artificial fusion, since the Sun fuses starting with ordinary hydrogen, not comparatively rare isotopes/elements like deuterium, lithium, or boron.)

Re:Old salt mine is the first emission-free compressed air e... by dredmorbius on Monday August 24, 2020 @03:31PM (#24264481)
I tend to agree generally WRT solar.

The usefully convertable fraction of solar on Earth may be far closer to present or anticipated energy demands than is commonly thought. Panel efficiency, spacing factor, lifetime, capacity factor, storage requirements, essential fuel-based needs (marine shipping, powered flight, mobile power, remote reserve generation & thermal), process energy (steel coking, Haber-Bosch, etc.) leave some large holes and very uncomfortable margins remaining.

The alternatives to solar are either secondary or tertiary options (biofuels, wind, wave) and hence, more limited, or comparatively finite (geothermal, possibly our best non-solar option, tidal).

I do largely suspect that humanity's future will be principally solar powered. The question is largely of how much energy and in what forms it will be available. And aagain, demographic trends and expectations shade strongly against pleasant transition.

I find Vaclav Smil's and the late David MacKay's works quite illuminating.

Re:Old salt mine is the first emission-free compressed air e... by legulere on Wednesday August 19, 2020 @02:44AM (#24207826)
There was a commercial thorium reactor in Germany, which was a financial disaster:

https://en.wikipedia.org/wiki/THTR-300

Re:Old salt mine is the first emission-free compressed air e... by MertsA on Wednesday August 19, 2020 @05:37AM (#24208680)
That was also a pebble bed reactor. The kind of reactor generating all of the latest hype is a molten fuel salt breeder reactor. There's a really substantial difference between the two and the MSRE was basically a mock up of the core running on Uranium fuel salt that would have been generated in a fertile Thorium blanket salt around the core and been reprocessed into the fuel salt.

Pebble bed reactors have tons of drawbacks that don't apply to most modern Thorium reactor proposals. The biggest drawbacks to proposals like e.g. LFTR is corrosion risks which were largely addressed by the MSRE ages ago, and the chemical reprocessing equipment which again is mostly a chemical engineering problem more so than a nuclear engineering one.

Re:Old salt mine is the first emission-free compressed air e... by belorn on Wednesday August 19, 2020 @03:35AM (#24208066)
To place it in the context of this compressed energy storage, when does the plant expect to be commercial viable through the method of buying energy cheap, storing it, and selling it expensive?

As far as I can find information, this plant is built on 30 millions given from the government. They have also got 17 millions from an equity round and 20 millions from a asset manager that supports building out clean-energy infrastructure.

In order to be commercial viable they need a significant overproduction in the energy grid from wind and solar which enable the company to buy cheap energy during peaks and sell it expensive during lows, and the difference need to be significant enough to pay both the energy loss, the operation cost and the investment costs. Wind and solar will also not over saturate the market beyond what is commercial viable for them, putting a short-term limit on how cheap the price can go during peaks.

Re:Old salt mine is the first emission-free compressed air e... by IfOnlyYouKnew on Wednesday August 19, 2020 @04:29AM (#24208348)
This is millions, while anything nuclear is measured in billions. And nuclear technology, including thorium, is decades old technology, unlikely to see the kind of rapid gains less mature technology frequently exhibits.
Re:Old salt mine is the first emission-free compressed air e... by bobthepanda on Wednesday August 19, 2020 @04:10AM (#24208255)
The tens of millions is a pretty cheap deal compared to nuclear power, which needs billions to get the ball rolling (and that's if it completes on budget)
Re:Old salt mine is the first emission-free compressed air e... by belorn on Wednesday August 19, 2020 @04:22AM (#24208302)
Its only a good deal if it produce profits. I rather have the government take a billion dollar cost in the energy sector that later turn a profit than a millions dollar cost that don't.

If neither can make a profit then that says something about the energy market. Turn off the fossil fueled alternative (or incrementally add a carbon tax until fossil fueled become commercial nonviable) and let see if the market price adjust to the point where the profitability of either goes into the green.

Re:Old salt mine is the first emission-free compressed air e... by nicoburns on Wednesday August 19, 2020 @04:41AM (#24208411)
> I rather have the government take a billion dollar cost that later turn a profit than a millions dollar cost that don't.

Surely that ought to depend on how much profit it generates. If it only generates a few millions in profit you're still down on your money.

Re:Old salt mine is the first emission-free compressed air e... by belorn on Wednesday August 19, 2020 @11:05AM (#24211092)
The first step is to be profitable, ie that revenue is higher than costs, and the second is that the rate of profit exceeds the investment cost over its lifetime.

A project is not commercial viable if it lacks either. Currently I have not heard of a single energy batter project that is profitable. The cost of buying energy together with employees and maintenance is significant above that of the revenue that they can get out. The hope is that if there is enough overcapacity in the future from wind and solar then the price will be low enough, and the electricity price during lows is high enough, that they could then make a profit. Nuclear in turn has seen mostly a drop in revenue while cost has only increased.

Choosing between two nonviable commercial options is a bad choice. I do however want an energy grid that is emissions free so one way or an other the economics need to change. Increasing the electricity price by kicking out fossil fuels is a good bet to help both technologies to be more commercial viable. Convincing wind and solar investors to over saturate the market and crash the price during peaks would be an alternative. Time will tell.

As a earlier article suggested, we need to actually do all of it if we want to reach the climate change goals. Pump more money into researching cheaper and more effective production of wind and solar plants that can saturate the market, research more effective battery solutions, kill fossil fueled power plants by aggressively tax them to death, and expand more nuclear plants.

Re:Old salt mine is the first emission-free compressed air e... by bobthepanda on Wednesday August 19, 2020 @03:56PM (#24215460)
A big problem with batteries as currently envisioned is that under a centralized utility model they don't "generate profit" per se.

Puerto Rico has post-Maria microgrids that are more resilient than the old utility model was to natural disaster, but they're making PREPA's financial situation worse, not better.

Re:Old salt mine is the first emission-free compressed air e... by pfdietz on Wednesday August 19, 2020 @08:21AM (#24209649)
Thorium produces just as much fission product waste as uranium.

And any thorium reactor is going to have to include 238U in it, or else the effectively high enriched 233U it DOES contain would be an unacceptable diversion risk (even with 232U contamination). That means it's going to produce more plutonium than you are letting on.

Re:Old salt mine is the first emission-free compressed air e... by roelschroeven on Wednesday August 19, 2020 @04:26AM (#24208322)
> The Netherlands just brought the first thorium powered plant online since the fifties.

Just to be clear, because one might get the wrong impression from how that was formulated (at least I know I did): what they have is a small test reactor, not a commercial electricity generating plant.

Re:Old salt mine is the first emission-free compressed air e... by AngryData on Tuesday August 18, 2020 @09:11PM (#24206175)
Im not sure uranium or other radiological material is really rare enough to call it non-renewable. Technically it isn't, but technically the sun doesn't last forever either. Nuclear materials can be found basically everywhere with rock or dirt, and much of it is recyclable into other nuclear materials down to the tiniest little bits. Just because we currently only want the richest and cheapest and least power intensive mines doesn't mean that is all we have available. It is like worrying about running out of iron, technically yes but realistically no.
Re:Old salt mine is the first emission-free compressed air e... by tonyarkles on Tuesday August 18, 2020 @06:12PM (#24204961)
If you replace “renewable” with “not based on burning hydrocarbons”, you’ve still got a dramatically better source of electricity than what most of the world uses.
Re:Old salt mine is the first emission-free compressed air e... by glogla on Wednesday August 19, 2020 @02:45AM (#24207837)
That's one of the issues with current energy policy of most of the world - the terminology and thinking is stuck in the days when everyone thought the problem is we're going to run out of oil or coal or whatever.

But that's not the problem humanity faces today - we will all die of climate change decades sooner than we run out of oil or gas or uranium. We should be focused on low/zero-carbon energy and not on renewability.