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Solar — it's not just a clean power source producing zero emissions and almost no local water impact, it's also now one of the best choices on the basis of how much energy you get back for your investment. And with climate change impacts rising, solar's further potential to take some of the edge off the harm that's coming down the pipe makes speeding its adoption a clear no-brainer.
In 2016, according a trends analysis based on this report by the Royal Society of London, the energy return on energy investment (EROEI) for oil appears to have fallen below a ratio of 15 to 1 globally. In places like the United States, where extraction efforts increasingly rely on unconventional techniques like fracking, that EROEI has fallen to 10 or 11 to 1 or lower.
Meanwhile, according to a new study by the Imperial College of London, solar energy's return on investment ratio as of 2015 was 14 to 1 and rising. What this means is that a global energy return on investment inflection point between oil and solar was likely reached at some time during the present year.
(Score: 2, Informative) by Anonymous Coward on Saturday December 24 2016, @03:52AM
EROEI is about energy, as the two E point, not money (at least, not directly... sooner or later some are unable to understand things if not translated to money terms). It means that 1 unit of energy used for something will give you X energy back, X:1. Unless the thing you get is used for other things, not energy, you want X to be >1 and the higher the better. Oil falling to 15 means oil extraction is becoming more energy intensive than before, "drill and get oil fountain" is becoming rare, while "drill, drill more... and more, then pump... pump harder, and clean what you extract to get acceptable oil" is becoming more and more common. At some point oil extraction only makes sense as feedstock for other processes (plastics, solvents, etc), not for energy purposes. http://www.sciencedirect.com/science/article/pii/S0301421513003856 [sciencedirect.com] has some numbers of past years like 1970 and also more recent.
Modern society, the one that develops new things, is said to become unsustainable if EROEI goes below 10:1, because you use too much of what you get to get the next batch, instead of use it to get other things. If you use 1 and get 2, you get only 1 to really use as the other 1 is needed for the next cycle, so 50% vs 50%. EROEI 10? You get 9 and 1 for the next cycle, 90% vs 10%. EROEI 100? You get 99 and have to use 1, 99% vs 1%. http://www.mdpi.com/1996-1073/2/1/25/pdf [mdpi.com] says EROEI 3 is barely enough to get along, having to cut in medicine or education (bye bye R&D). https://books.google.com/books?id=SRocBQAAQBAJ&pg=PA27&lpg=PA27&source=bl&ots=bedj9G2VD_&sig=Z-pLySOgClHzHDu_KTwzvDqqzRg&hl=en&sa=X&ved=0ahUKEwjZ5sHk7YvRAhXCqxoKHerYBLwQ6AEIOTAH [google.com] talks about 5:1 or 10:1 as minimum to keep a half modern civilization, instead of just a dying one as with 3:1. https://www.scientificamerican.com/article/eroi-charles-hall-will-fossil-fuels-maintain-economic-growth/ [scientificamerican.com] mentions again 5:1 for a spartan one, going up as you add things we take for granted as "civilized" and with options to keep adapting to future challenges (by means of education, healthy population, R&D).
To see the energy of a project check http://www.theenergycollective.com/barrybrook/471651/catch-22-energy-storage [theenergycollective.com] and scroll down to the graph with triangles and bars. Last graph, a pyramid, has EROEIs for things like art or grow food, again matching what more or less said before, 5:1 is barely enought to keep rolling, support anyone beyond involved workers is 7:1, education needs 9:1. It even talks about the EROEI of pumped hydro, "amazing" 35:1 (49:1 for plain hydro), and later says we can not use storage for a transition away from fossil fuels. That's a facepalm moment. Thinking nuclear plants can idle without wasting energy and start and stop at will, or that we solved the residue handling (if tech or politics problem doesn't matter, we have not yet and don't seem to want to, we just pass the hot potato around) is also a WTF. What is more, I know of handful places in which there is pumped hydro to save the nuclear output at valley moments and be able to supply at peak ones.
(Score: 2) by Aiwendil on Saturday December 24 2016, @07:53AM
Steam bypass (feature of most modern reactors) and use that for process heat (in siberia it is used for central heating, in some parts of the world it is used for desalination).
Having processes that can stand being unpowered for a while (days, weeks) makes this even more aftractive.
Nuclear is interesting in that regard, unless you have hydro (save water) or pumped storage (fill upper reservoir) or fastacting plants at neighbour grids (export) it often is cheaper to just co-place it with industrial processes that needs heat.
Heck, modern nuclear engineering intro courses even traina people to provise a rough estimate at how it will perform at various steam bypasses (or if they can take higher heat prior to the steam generators)
(Also - modern nuclear reactors can cycle down to between 40% and 60% in about an hour, and then ramp up to 95% at a rate of 3-5% per minute. Coupled with steam bypass this allows for very interesting options)
(Score: 2) by Ayn Anonymous on Sunday December 25 2016, @02:36AM
So all you nuclear power calculator here let the nuclear waste sit somewhere unattended, unwatched, unprotected ?
Yes ?
No ?
So let's say just one guy is looking after it.
For just minimal wage. $15
24h of course.
So, 24 x 15 = $360 per day.
$131,400 per year.
Half-time of plutonium is 10,000 years.
It will probably take 10 times half time to call it not "EXTREME dangerous and toxic".
That's: 13,140,000,000 13 billion dollar for some thousands tones of this nuclear waste shit.
Only one with a mental disorder believe that mankind can protect something for 100,000 years.
So, you are totally stupid or member of the nuclear cartel a...holes, or suffer from a mental disorder not to get what the REAL problem with nuclear power is.
Hint: it is no running them safely.
(Score: 2) by Aiwendil on Sunday December 25 2016, @10:30AM
Or we could just chuck the spent LWR fuel into CANDUs, set up breeders and the run a global nuclear programme long enough that we pass the time needed for storage (which - with the abice setup - reduced to less than 10k years).
Or we could chuck the spent LWR fuel unto CANDUs and breeders, and destroy the remaining stuff more active than U238 in an ADS. (From a technical point if view the waste issue was solved back in the 50s - we just need to push the price down and get politicians to allow us to build other types of reactors at a significant scale).
And since you insist there is no way to run a reactor safely then please tell me what failure modes you worry about with CANDU, AHR, HTR-PM, , IFR, ADS, ABB BWR 90+ or an ESBWR.
(Oh, and noone seriously considering nuclear in the long run considers only a single family of technologies [with the exception of ADS])
The notion that you must store nuclear waste in more strict ways than scrap metal is not really true if you're willing to fully use available technologies (it just is easier and less of a political hassle to store it - and most long term storages considered/under construction are designed to be sealed off unless you at least have the technology we got in the early 1900s (so - assuming next time round we rediscover everything at our current once there will be less than 40 years between when we could breach into a repo until we learn how we should approach it, and given the depths of the repos it will take a few decades to breach them with 1910s technology. Oh, and where long term storages are planned to be built are where the bedrock isn't expected to change for a couple of million years [excepting east asia - where the tectonic plates are expected to be melted in the even more radioactive innards if the earth])
(Btw; the halflife of Pu-239 is about 24k years, and it is the third most stable isotope of Pu - and it is easy enough to use that it is insane to send it to storage instead of fissioning it. And while at it - you are aware the toxic properties of nuclear waste has nothing to do with radioactivity?)