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Post by Barry Brook on Nov 15, 2012 17:51:37 GMT 9.5
A new post has been published on BraveNewClimate. Link here: bravenewclimate.com/ewp2012-hazy-future-visionThe Energy White Paper 2012 (EWP2012), released by the Australian Government last week, seeks to map out a strategic policy framework for future energy supply. One of the major goals of EWP2012 is to provide a “clear vision” of how Australia should set about the long-term task of decarbonising our stationary electricity, liquid fuels and industrial sectors. So how well does it succeed? This BNC post gives an answer... This BNC Discussion Forum thread is for the comments related to this BNC post.
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Post by John Morgan on Nov 15, 2012 22:16:15 GMT 9.5
Way back when the Energy White Paper was the Draft Energy White Paper I wrote a post for BNC that highlighted this text in Box 6.3: and asked: What, precisely, is this timeframe, and when does this option on a non-nuclear future expire? Whatever it was when I wrote that article, its one whole year less now, so we’d better figure it out soon.
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Post by Cyril R on Nov 15, 2012 23:03:01 GMT 9.5
So there´s no social consensus on nuclear power?
That means there must be a social consensus on hydroelectric, onshore wind, and CCS, huh?
Oh yes, another great objective `study`. Somebody must be breeding these researchers, since they all have the same nuclear is no good bias.
This is really bad news. Because it means the debate on nuclear hasn´t change. Still taboo.
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Post by proteos on Nov 16, 2012 7:10:25 GMT 9.5
I am quite surprised by the results of the simulator: coal dominance will only start to wane in 2030! It looks like Australia has plenty of coal & lignite plants that are authorized to run up to that year.
If some coal plants must be replaced before then, and are replaced by other coal plants, nuclear won't develop like in the simulation: the place in the generation mix will be occupied since a coal plant can last up to 50 years. Thus, there is a risk of lock-in that is not captured by the scenario. And that would most certainly translate into higher CO2 emissions.
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Post by anonposter on Nov 16, 2012 16:04:15 GMT 9.5
So there´s no social consensus on nuclear power? That means there must be a social consensus on hydroelectric, onshore wind, and CCS, huh? Oh yes, another great objective `study`. Somebody must be breeding these researchers, since they all have the same nuclear is no good bias. This is really bad news. Because it means the debate on nuclear hasn´t change. Still taboo. There isn't a vocal and very well-funded minority opposed to them (and there probably won't be much if any new hydro in Australia, we'll just end up keeping what we've got running which we should do anyway).
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Post by Alberto R on Dec 7, 2012 5:42:25 GMT 9.5
CCS really? Did australians ever heard of lake Nyos? en.wikipedia.org/wiki/Lake_Nyosa little gem: "suffocating some 1,700 people within 25 kilometres (16 mi) of the lake". I would not live near a CCS site...
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Post by grlcowan on Dec 7, 2012 6:59:40 GMT 9.5
CCS really? Did australians ever heard of lake Nyos? en.wikipedia.org/wiki/Lake_Nyosa little gem: "suffocating some 1,700 people within 25 kilometres (16 mi) of the lake". I would not live near a CCS site... There will, of course, never be any need for CCS sites of kinds that can leak; see also the recent olivine thread. But even if that were not so, your argument is not valid. It compares a natural deposit of CO2, which nature has no interest in making leak-resistant, with man-made ones made by humans with every interest in that. You might as well say stones cannot be weapons because they won't accurately throw themselves.
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Post by anonposter on Dec 7, 2012 12:04:03 GMT 9.5
But even if that were not so, your argument is not valid. It compares a natural deposit of CO2, which nature has no interest in making leak-resistant, with man-made ones made by humans with every interest in that. You might as well say stones cannot be weapons because they won't accurately throw themselves. Whilst we'll be able to do better than nature I should note that nature hasn't done as well at containing CO 2 as it did containing nuclear waste from the Oklo reactors. Even though we could probably find some suitable geology in the middle of nowhere (I don't want CO 2 stored anywhere near me, it's a gas (or maybe it'll be stored as an SCF) that will try to escape anyway it can, it isn't like nuclear waste which will just sit there quietly) I still don't think it'll ever be as safe as a nuclear waste dump.
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Post by Alberto R on Dec 7, 2012 21:59:22 GMT 9.5
CCS really? Did australians ever heard of lake Nyos? en.wikipedia.org/wiki/Lake_Nyosa little gem: "suffocating some 1,700 people within 25 kilometres (16 mi) of the lake". I would not live near a CCS site... There will, of course, never be any need for CCS sites of kinds that can leak; see also the recent olivine thread. But even if that were not so, your argument is not valid. It compares a natural deposit of CO2, which nature has no interest in making leak-resistant, with man-made ones made by humans with every interest in that. You might as well say stones cannot be weapons because they won't accurately throw themselves. It's gas. All that you need is a little earthquake and you have potentially thousands of deaths. Storing gas under the carpet is pure folly.
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Post by Roger Clifton on Dec 9, 2012 18:24:08 GMT 9.5
Grlcowan said: "There will, of course, never be any need for CCS sites of kinds that can leak", referring to an intention for permanent storage. However shorter term storage does happen and may be touted as qualifying for CCS status.
Gas production platforms routinely sequester large quantities of CO2. This is a safety measure as much as anything. Incoming gas, although rich in methane, is anywhere between 10 and 50% CO2, which is commonly washed out under pressure. If the wash water were simply dumped over the side of the rig, it would effervesce CO2 and suffocate the men on the rig.
If the rig is located in deep enough water, the mixture can be released near the seafloor, where the emerging CO2 redissolves in a larger quantity of seawater, to re-enter the atmosphere at some safe distance from the rig. And coincidentally, a safe distance from the environmental watchdog's instruments -- a good reason to monitor from satellite.
Reinjection deeper into the original gas reservoir is possible -- potentially true CCS -- but it is expensive and the operator is likely to be driven by cost to inject into shallower sediments, clear of the valuable production zone. There is unlikely to be a long-term gas trap anywhere between the seafloor and the trap from which the methane was extracted, but it would be easy to find a depth where the escape time would be longer than the lifetime of the rig. It would not escape the attention of their spin merchants that this time could be long enough to claim credit for CCS but longer than a watchdog could monitor and punish for its escape.
High pressure CO2 reacts with water to create a strongly buffered acid, so it proceeds to attack the rock around it. There is always some slow cycling of water through sediments, especially likely when the sediment has been disturbed by the initial overpressure then subsequent crumbling of the acidulated rock. When any of the CO2/water reaches a shallower level where it can effervesce, buoyancy begins to drive circulation and inevitably creates a widening pathway for the escape of the CO2 through the seafloor. A cynical claim for CCS might assure the regulator that the timescale for this process is long enough, though it would need to be longer than the lifetime of our species.
The rig operator may instead recycle the wash water, getting a quite pure stream of CO2 that can be reinjected as is. It is true that as a pure gas it is buoyant, but as it is compressed for injection at depth, CO2's buoyancy decreases until it liquefies at a pressure equivalent to around 700 m depth of water, becoming denser than the water in the pores of of the sediment. Here the bulk of the liquid CO2 would initially tend to sink rather than rise through the sediment as the pore fluids move to adjust to the injection, and thus be claimed as safe CCS. However the mixing zone between the CO2 liquid and sediment water becomes the same corrosive acid as before, and containment is no longer certain.
When compressed and injected somewhere around 1000 m depth of rock, such that the geothermal temperature exceeds the critical temperature of CO2 at 30C, the CO2 becomes a supercritical liquid. Its density is then half that of the surrounding water and it has become compressible again. If such a reservoir of heated supercritical CO2 ever gets an adiabatic escape pathway to the surface, escape would be certain and eruption may occur.
A regulator must be able to independently check where the CO2 is being placed to grant CCS status to an injection. Subsequently the regulator would need independently monitor its movement.
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Post by janisspiker on Oct 29, 2014 15:23:32 GMT 9.5
I am new here and just joined to know more about nuclear energy, because i have to submit an assignment paper related to this. I am really glad to be a part of this site
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Post by David B. Benson on Oct 30, 2014 7:12:57 GMT 9.5
janisspiker --- Welcome. Feel free to ask questions. There are many quite knowledgeable commenters available to (eventually) answer.
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Post by jagdish on Oct 30, 2014 19:19:45 GMT 9.5
So there´s no social consensus on nuclear power? That means there must be a social consensus on hydroelectric, onshore wind, and CCS, huh? Oh yes, another great objective `study`. Somebody must be breeding these researchers, since they all have the same nuclear is no good bias. This is really bad news. Because it means the debate on nuclear hasn´t change. Still taboo. There isn't a vocal and very well-funded minority opposed to them (and there probably won't be much if any new hydro in Australia, we'll just end up keeping what we've got running which we should do anyway). Taking a charitable view of coal, it may become possible to carry out underground hydrous pyrolysis of coal using nuclear steam, adding energy to it without creating dust. The chemicals formed in the process particularly hydrocarbons,alcohols,aldehydes and ketones could be taken out as vapors, condensed, and used for various purposes including fuel.
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Post by Greg Simpson on Nov 3, 2014 7:14:49 GMT 9.5
Taking a charitable view of coal, it may become possible to carry out underground hydrous pyrolysis of coal using nuclear steam, adding energy to it without creating dust. The chemicals formed in the process particularly hydrocarbons,alcohols,aldehydes and ketones could be taken out as vapors, condensed, and used for various purposes including fuel. The fuel part doesn't do much to prevent climate change, though. It might be useful otherwise.
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