"Now everyone was giving her that kind of look UFOlogists get when they suddenly say, 'Hey, if you shade your eyes you can see it is just a flock of geese after all.'"
"You can't erase icing."
"I can't believe it doesn't work! I found it on the internet, man!"
There have been a couple of things going on in the developed world over the past couple of decades with reguards to electricity generation. The first is deregulation/privatisation. The results of this have been very mixed as if it is done done badly it can result in inefficiency and high costs for consumers as electricity supply is a natural monopoly and when done badly it can result in very high prices for consumers as customers have no easy way to get an alternative supply of electricity if the power company owns both the generating capacity and the grid that is connected to their house or business. Another trend, which has been mixed in with deregulation and privatization, is a shift towards more market based selling of electricity. In Australia this has generally been achieved by splitting electical supply into suppliers that generate electricity and distributers that sell it to people over the grid. This helps prevent monopoly, although the Australian system does have it's drawbacks. A couple of years ago distributers in South Australia had to briefly pay about $4 US a kilowatt-hour because the largest power plant decided to hold back supply to force up prices. (Something comparable happened on a huge scale in California.) Market based electricity markets work against nuclear power as nuclear plants have extremely long pay back periods and competitors pushing down prices introduces risk and can result in massive losses for the reactor owners.
Ronald, how does the start-up cost of a dam compare to that of a nuclear plant? Are big ones in the same ball park? Or not even close?
Looks like the saucer aliens shafted the earth rubes for a fusion power plant.
I wonder what the aliens got in return?
Or is it politicals a different species.
That depends on a lot. Usually the sites that are cheapest to dam in a country are used first and the price increases for less suitable sites and in addition to electrical generation there are also the benefits of water storage and flood control as well. Also, hydroelectricity has advantages over nuclear power in its very low operating costs and because it can adjust its output to be load following while nuclear power is base load. But generally hydroelectric schemes that have been built are lower in start-up cost than nuclear power. Potential hydroelectric power sites that remain in Australia would be cheaper to construct than nuclear power, however new and existing hydroelectric schemes in temperate Australia are at risk from climate change which is drying up much of the continent.Ronald, how does the start-up cost of a dam compare to that of a nuclear plant? Are big ones in the same ball park? Or not even close?
The three gorges dam in China will have a cost of around $30 billion US when complete and will have an average output of about 11.4 gigawats. This is less than half the start up cost of the new nuclear reactors of French design that are going to be built in China, although older model reactors under construction in China may be cheaper. Hoover dam cost about $736 million in today's money and has an average output of nearly .46 gigawatts. That's less than a third the start up cost of new nuclear power in the US. Of course, when Hoover dam was built nuclear power was not an option.
Thanks Ronald. I'm still trudging through everything. There's quite a lot.
Apparently these guys can do nuclear fusion for $50 million Canadian... and the Canadian government has said it will match private financing under certain conditions..
I mean, if ITER is billions and the NIF was billions.. 50 million is pretty cheap for a fusion experiment.. I think it would be worth it even if it was just a shot in the dark.. 50 million is nothing in terms of what has already been spent on fusion technology.. After converting to US dollars the cost is probably significantly below 50 million.. in any case.. I hope you guys go to the site and check it out..
Fusion Power is the holy grail of green technology and it would solve the energy crisis as we know it provided it could be made commercially viable..
something tells me the oil cartels and the media are going to try to push this entire project into the Pacific Ocean before anyone notices it...
Worth a shot.
And I presume you mean the oil majors? The oil cartel, OPEC, is a bunch of countries. If someone gets fusion to work, and it truly is a game changer, and if the oil majors are still around, I'd expect one of them to buy the method. Er...that's what I'd do anyway.
but in the grand scheme of things and relative to what has been spent so far 50 million is nothing.
If fusion is "green," so is conventional nuclear. Fusion would have some of the same issues as nuclear fission, like radioactive waste and possible use in weapons production. I'd be happy to see practical fusion, but I expect that the same people that oppose conventional nuclear would also oppose fusion. Personally, for now, I'd like to see more research on advanced fission reactor (Gen IV) designs, and more commercial use of current reactors. We know conventional nuclear works.Fusion Power is the holy grail of green technology and it would solve the energy crisis as we know it provided it could be made commercially viable..
I say there is an invisible elf in my backyard. How do you prove that I am wrong?
The Leif Ericson Cruiser
Magnetized Target Fusion, which is legitimate enough. General Fusion has an interesting design; they use a spinning liquid metal/lithium mixture to capture neutrons, and basically can pump the mixture out of the reactor to heat exchangers. Because the mixture is spinning, they create a vortex in the center where the reaction can take place without coming in contact with metal (the quenching problem). The lithium also protects the reactor structure from neutron embrittlement, and tritium can be extracted from it to produce more fuel. The inertial compression is done via large mechanical pistons arranged in a sphere around the fuel, which fire together to create a compression wave and initiate fusion. Pulse time would be about 1 second, which keeps the magnetic confinement relatively simple.
Until they try to build one, I doubt they'll know the full list of engineering problems they are going to face. Keeping the pistons in sync might be hard, and there are a lot of high temperature moving parts involved in the liquid lead-lithium vortex. Maintaining the vortex accurately enough to avoid fuel-metal contact might be tough. Unexpected energy losses in general might doom the approach.
They do have big cost advantages over pure magnetic and pure inertial designs, but that won't matter if they never achieve ignition.
In addition the waste produced by a fusion reactor is apparently a small fraction of the waste produced via fission. Also, the fusion waste products are apparently easy to recycle.
Also, since fusion is more efficient at converting mass into energy, the number of fusion plants which need to be built should be less than the number of fission plants. Therefore from a land-use perspective fusion is also superior (incidentally massive land-use is also a huge drawback for wind and solar technologies).
I agree though that the dangers of nuclear fission are way over-hyped and I would have no problem living next to a fission power plant. The Chernobyl incident has certainly given fission a bad name even though the Chernobyl reactor was based on a 1930's reactor model design and appears to have been sabotaged. I guess Chernobyl proved that if scientists want to they can induce a melt down in a fission plant. I think current reactors such as CANDU have triple redundancy systems which prevent operator error by shutting the system down in the event of a possible meltdown sequence. Turning off a fission plant and turning it back on is apparently very expensive.. but is obviously better than a meltdown.
On the other hand just look at what France has done with nuclear fission. I think it's fantastic. The high air quality there no doubt has a lot to do with the fact that 75% of the nations power comes from nuclear fission. The French economy will really benefit in the coming years because: a) it can export its nuclear technologies to other countries and b) it can sell its excess electricity to England and Germany. It's interesting that ITER ended up being build in Cadarache France. I think that there is a strong political will in France to be at the forefront of all nuclear technology.
As to CANDU reactors - all western nuclear plants have multiple redundancy in their engineered safety systems.
As to the French nuclear program, I agree they have a working system, and great political will to sustain it. Don't know about the rest. Their technology is about the same as the US and Japan.
Regarding safety of fusion versus fission, I found this on Wikipedia (please let me know what your opinion is on this):
original Wikipedia article:The likelihood of small industrial accidents including the local release of radioactivity and injury to staff cannot be estimated yet. Nevertheless the likelihood of a catastrophic accident in a fusion reactor resulting in major release of radioactivity to the environment or injury to non-staff, is estimated to be much smaller than that in a fission reactor. The primary reason is that the fission products in a fission reactor continue to generate heat through beta-decay for several hours or even days after reactor shut-down, meaning that a meltdown is possible even after the reactor has been stopped. In contrast, fusion requires precisely controlled conditions of temperature, pressure and magnetic field parameters in order to generate net energy. If the reactor were damaged, these parameters would be disrupted and the heat generation in the reactor would rapidly cease.
There is also no risk of a runaway reaction in a fusion reactor, since the plasma is normally burnt at optimal conditions, and any significant change will render it unable to produce excess heat. In fusion reactors the reaction process is so delicate that this level of safety is inherent; no elaborate fail-safe mechanism is required. Although the plasma in a fusion power plant will have a volume of 1000 cubic meters or more, the density of the plasma is extremely low, and the total amount of fusion fuel in the vessel is very small, typically a few grams. If the fuel supply is closed, the reaction stops within seconds. In comparison, a fission reactor is typically loaded with enough fuel for one or several years, and no additional fuel is necessary to keep the reaction going.
I'm always pretty skeptical about Wikipedia.. but this particular quote seems to be suggesting that 'runaway reactions' are possible in fission, but not likely in fusion. (It does seem to confirm the idea that decay heat is the culprit though..)
here is one of the original articles which misled me: http://science.jrank.org/pages/4754/...trol-rods.html
I remember reading somewhere else too that the control rods were used to prevent 'runaway' reactions and explosions..
but thanks for the corrections.. I appreciate it.... it's hard to know what to believe on the internet.. maybe I should just stick with textbooks..sigh..
The worst danger in a nuclear reactor is meltdown, where the reactor puts out enough power to melt its own structure and fuel. This can lead to steam explosions, but can never lead to a nuclear explosion, and as the core falls apart it will eventually cease to be able to sustain a reaction. Some more modern reactor designs are designed to melt down safely if all other protective systems fail, dividing and containing the molten material to halt the reaction, others simply can not melt down, no matter what happens.
Maybe he's Sithum is thinking of a nuclear excursion/criticality accident.
Et tu BAUT? Quantum mutatus ab illo.
The physical geometry of a reactor also bars a nuclear detonation. Even in naval reactors, which are enriched to 93% U-235 (or were, in my day), it is impossible to achieve.
Fusion plants thermally producing power would have similar hazards, as well as new ones. While they would immediately stop producing power when shut down, they are also likely to involve large superconducting coils full of cryogenic coolant. As the recent accident at the LHC shows, such coils are not free of problems...they can "quench", losing their superconductivity and dumping their stored energy in an instant as heat, leading to rapid vaporization of coolant. This could cause damage to the reactor and the surrounding building and possibly lead to release of radioactive materials produced by neutron radiation from the fusion reaction. Any fires that start should be thoroughly extinguished by the blast of boiling helium, though...
It's certainly still worthwhile, fusion does have some advantages, and learning to harness it seems likely to lead to side benefits of the technology developed. It's just not as utterly superior an approach as was suggested.
The advantages, so far, for fusion over fission:
1) reduction in mining activity (therefore less waste at the fuel acquisition step).
2) far higher energy yield per kilogram of fuel versus fission (less fuel required in the first place for a given amount of energy production..)
3) cleaner waste products (shorter half-lives, easier disposal/recycling etc).
4) Fuel seems to be far more abundant (therefore fusion will likely be a better long term solution for power generation)
5) safer operations according to some sources (see below).
6) more research potential?
Advantages for fission over fusion:
1) existing technology (therefore less expensive in short term).
2) has been tested and refined (reliability will be higher in short term as an adequate power source).
3) can use fuel from warheads to power fission reactors (can use to reduce nuclear war head stockpiles from the cold war era etc.,).
4) modular designs (such as pebble bed) available meaning that some plants can be expanded as energy demand increases (will this eventually be possible with fusion as well though?).
Remember, we've got so much depleted uranium lying around from the weapons programs that we use it in bullets...and while it's useless for nuclear weapons, it can be burned in reactors. There's enormous quantities of uranium still un-mined, and there's far larger thorium reserves. We're not going to run out of fission fuels for a long time.
Another advantage for fission would probably be compactness. It's looking like practical fusion plants will be too big for things like aircraft carriers and any but the largest spacecraft.
It seems according to this source that the amount of uranium being consumed today far outstrips its production(check out the graph--source: http://www.world-nuclear.org/info/inf23.html)
I think it may be more meaningful though to compare what the total lithium supply is versus the total uranium supply. According to the above article the total amount of uranium available from 'known recoverable sources' is 5,469,000 tonnes. Total elemental lithium supplies seem to be currently estimated at around 28.4 million tonnes (http://www.worldlithium.com/An_Abund...%20Lithium.pdf).
The other thing to consider with lithium though is that it is used in so many other applications such as electric/hybrid car batteries and hand held electronics (it is also used in medicine, but I think the amount used here is fairly negligible). Total lithium consumption per year now is apparently around 84,000 tonnes of lithium carbonate (total amount of lithium carbonate in the world according to this article is 150 million tonnes--source: http://www.energybulletin.net/node/48026). Of course consumption is increasing and will continue to increase significantly in the foreseeable future given the direction of the auto-industry and electronics in general. However it seems that there is an abundance of lithium.
Also, it would seem that there is significantly more lithium around than uranium.
Another thing I wanted to ask: what are the other ways of making tritium? Apparently tritium can also be produced by bombarding deuterium atoms with other deuterium atoms(http://www.bookrags.com/research/tritium-woc/). Would it be better to produce tritium in this way?
I would like to do a hypothetical comparison:
Part A: If we took all the feasibly fusible material on the planet (by feasible I mean material that could be feasibly mined/produced/extracted and put into a commercially viable nuclear fusion plant to generate power) and produced energy via fusion what would the total energy output be?
Part B: If we took all the feasibly fissible material on the planet (again by feasible I mean material that could feasibly be used to power a nuclear fission power plant) and produced energy via fission what would the total energy output be?
Would part A not yield way more energy than part B?
I thought that because of the superior mass-energy conversion efficiency of fusion versus fission and because of the abundance of deuterium and lithium versus uranium, the potential amount of power producible over the long term by fusion would be far more than that which could be produced via fission (would it be several orders of magnitude higher?..I don't know.).
Would this not imply that over the long term fusion may eventually be 'the way to go'?
let me know what you think,