Nuclear & other power source discussions

[Urwumpe]

What are those energy storage technologies? From what I know cheapest energy storage technology is hydroelectric dam - when there is plenty of wind power generated you shut the gates and let the water acumulate for usage when wind is low or in more advanced design pump the water up the dam with surplus electricity. However this method is very location dependent. Do Germany have any significant unexploited good hydroelectric sites. I mean if you want to run a large country on intermittent energy sources like wind and solar you have to have dirt cheap means of storing for long periods of time megatons worth of energy.

There are also pump power plants, which pump water upwards during times of excessive power, and let this water run through turbines when there is a higher demand. Such pumps are already used today for reacting to short term demands and cause less ecologic damage since they require no natural water flow to be obstructed.

There are also battery storages, which can power a whole quarter in a city for days, but these are still a bit expensive (But much more effective as pumps).

 

[jedidia]

But the big energy companies are currently in the way for this, because they do everything to prevent having to invest money into infrastructure.

Somehow the attitudes of your energy companies are somewhat scary. Nuclear power can indeed be dangerous if not handeled properly, and from what I gather germany was handling it pretty sloppy for at least a decade now...

 

[Jamesep3]

I think this sudden rush out of nuclear power isn't a smart idea. Nuclear power isn't egsactly the best but the problem is the world does not have any current reliable, safe way of disposing all the used fuel. The fuel rods may be harmless when they go in to a reactor ( so harmless you could be in the same room as one) but once they come out they are increadibly dangerous ( can't be in the same town as one), and the world so far has not solved the problem of these used fuel rods. If we all stop using nuclear power now what do we do with the waste????:uhh:

 

[Urwumpe]

I think this sudden rush out of nuclear power isn't a smart idea. Nuclear power isn't egsactly the best but the problem is the world does not have any current reliable, safe way of disposing all the used fuel. The fuel rods may be harmless when they go in to a reactor ( so harmless you could be in the same room as one) but once they come out they are increadibly dangerous ( can't be in the same town as one), and the world so far has not solved the problem of these used fuel rods. If we all stop using nuclear power now what do we do with the waste????:uhh:

I am for storing them at the homes of all politicians who decided to build dozens of nuclear power plants before having a solution for the waste.

Even without nuclear power, we would have tons of nuclear waste every year, but nuclear power production produces most of the worst category. The spent fuel rods aren't even as dangerous as the stuff that is produced during reprocessing of the fuel rods.

Nuclear power is of course not harmless, but also not that extremely dangerous if handled properly. The problem is just, handling nuclear power properly can't be done by the current organizational structures. The people who balance between economics and security are not responsible for any damages of their decisions, and often have no clue about failure management or failure tolerance.

Essentially, we are having nuclear power plants now, that have only a lot of pretended redundancy. The dependencies between subsystems are so large, that a failure of one does not exclude the failure of another. For example, in a German nuclear power plant, we have four Diesel Generators, but all are at the same building level, a flooding in the building (eg by a burst tank or water line) would take all Diesel Generators at once out of service.

As long as such obvious errors are tolerated by too industry friendly agencies and the operation of the plant in the hands of companies who would prefer profits over safety as long as no agency complains, nuclear power is only waiting for the next disaster.

 

[hribek]

The investments in solar power will be reduced a lot in the future, they have already passed the point, where the solar power subsidies turned into something harmful by far. We have now too many expensive solar power installations, that are economically at bad places.

Your country is not the only one. In fact the subsidies have had a higher distorting effect in here - I'm not aware of any power limits per installation in this country.

As this very terrifying situation is ongoing, regardless of severity, I am really annoyed by the fact that anti-nuclear people will use (and are already using, most likely) it as a reason to abandon nuclear energy.

It is not. A mishap is a mishap, a disaster is a disaster (God forbid), but when it's finished you pick yourself up and make sure it doesn't happen again. You don't give up and run away.

I agree with that, and my permanent home is about 20 km from a nuclear powerplant. The alternatives are not very promising.

 

[Jamesep3]

I am for storing them at the homes of all politicians who decided to build dozens of nuclear power plants before having a solution for the waste.

:lol: I agree:lol:

 

[Belisarius]

The most important thing in discussing nuclear power is that there's transparency and honesty, two values which are totally lacking on the part of authorities. In this respect the story of Katsuhiko Ishibashi (professor of public safety at Kobe University) is most illuminating.

http://www.planet.sci.kobe-u.ac.jp/study/list/seis/ishibashi_e.html

In 2007 he resigned in protest from Japan's nuclear energy safety committee

Katsuhiko Ishibashi, a professor at Kobe University specializing in earthquakes and urban safety, was a member of a committee that set new earthquake safety guidelines for Japan's nuclear reactors last year. He said some of the committee's 20 members were scholars and engineers with close ties to power companies, including one who advised those companies.

Mr. Ishibashi said the guidelines, approved in September, were too vague and left too much discretion to power companies in deciding whether a plant site was seismically safe. He said he got so angry at the lack of discussion in the committee about the new guidelines that he resigned in disgust at the final meeting.

http://www.nytimes.com/2007/07/24/w...ed=2&_r=1&sq=Ishibashi Katsuhiko&st=cse&scp=4

He received no support from professional colleagues but continued to warn people of the danger of building nuclear plants on fault lines through articles published in the International Herald Tribune and elsewhere.

From the NYT we read the response of his critics in 2007:

Plant operators and government regulators call those criticisms unfair. They say the companies' plans face intense scrutiny from committees of independent scholars. They also say the Kashiwazaki plant was just unlucky: The earthquake struck a year before Tokyo Electric was to finish a seismic survey to ensure that the plant met the standards of the new earthquake safety guidelines.

Finally, his words went unheeded. Right now on BBC radio I'm listening to another "expert" who says the Fukushima incident was all bad luck. But it wasn't bad luck, it was bad planning and a complete lack of recognition of the real risks involved.

Notice the strategy of blaming bad luck was used in 2007, and the "new standards" were supposed to eliminate the luck element and make it invulnerable to all and any foreseeable risks. Then also consider that the Indonesia tsunami happened at the end of 2004, more than 2 years before the discussion quoted above.

Nothing about this disaster was unpredictable. Again, from the 2007 article:

The strength of the earthquake in Kashiwazaki ''could have been predicted, and should have been predicted,'' Mr. Ishibashi said. ''The new guidelines are very insufficient and have loopholes.''

Today Professor Ishibashi is becoming very famous indeed as a Cassandra figure. But in 2007 when he should have been listened to, he was ignored and sank into obscurity. Complacency and cost-cutting were the priorities then and were implemented by the government of Japan and the private industry of nuclear power generation, supported by a huge chorus of paid World Nuclear Asssociation spokespeople.

Right now in Europe the most urgent thing to do is to stop the Berlusconi programme to construct 4 Italian nuclear power stations in 2013. In 1990 Italy was wise enough to recognise that nuclear power was a massive risk in an earthquake zone and decommissioned the last of their old nuclear stations.

With the evident corruption in the political and judicial system in Italy, the government there is not to be trusted to enforce any kind of safety regulation. Oversight should be immediately passed to the EU, and taken out of the hands of Berlusconi's mafia-style authority.

(As a side-note, polls indicate that only 20% of Italians approve the building of the nuke stations, but as it has not been a priority issue until now, that has not harmed Berlusconi's electoral chances, but that it sure to change now.)

As a general reference to the foregoing - not to be taken as authoritative, but contains the most important links:

[ame="http://en.wikipedia.org/wiki/Nuclear_power_in_italy"]Nuclear power in Italy - Wikipedia, the free encyclopedia[/ame]

 

[Tommy]

I have always had two problems with nuclear power.

One is the waste. Here in the US, the "long term" storage plan is to put the waste in a repository that is alleged to be safe. Never mind that an Earthquake occurred (over 8.0 on the Richter scale) with an epicenter only 50 miles from the proposed repository, and the repository is only designed to withstand quakes of less than 6.5 magnitude (the site has since been "disqualified" - and no new site has been proposed, much less approved).

Nuke proponents claim that power plants are designed to exceed the expected threats - but so was the plant in Japan. We (humans) aren't nearly as smart as we would like to think - nature has repeatedly acted in ways that "exceed" our expectations. The reactor in Japan is a prime example - it was thought that it could easily withstand any quake/tsunami that came it's way (expectations were based on a very limited historical sample). Turns out it it couldn't handle what nature had to throw at it.

I'd like to raise two points in response to the "where is the energy going to come from" crowd.

1: Here in the US, there are over 35,000 "flood control" dams. These dams are used to regulate rivers and prevent floods - and none of them are used to generate power. The vast majority of these dams are past their expected lifespan - and are over due for repair/replacement. While most of these dams wouldn't be capable of generating megawatts individually, combined they could more than replace the power generate by ALL the nuke plants in the country. These dams already exits - no "new" environmental damage would be created by converting them to hydroelectric power stations.

2: More money has been spent researching nuclear power than has been spent researching ALL OTHER "ALTERNATIVE" ENERGY SOURCES COMBINED. 'Nuff said.

Nuclear power is only "cheaper" than the alternatives because the government heavily subsidizes nuclear power. Actual costs of nuclear power are higher than wind, solar, or hydroelectric.

While we are at it, let's look at the whole "global warming" thing. It's obvious that humans contribute to (but aren't the sole cause of) global warming. Currently, CO2 emissions are the scapegoat. I maintain that CO2 emissions aren't so much the cause of global warming as they are a symptom of the REAL cause. The real cause of global warming is the Second Law of Thermodynamics.

The real cause of global warming is Entropy. Energy can not be converted from one form to another with perfect efficiency, and the "waste" energy is almost always dispersed as heat. That's why cars have radiators - to disperse the wasted energy when we try to convert chemical energy (contained in fuel) into kinetic energy (the motion of the car).

Nuclear Power plants generate enormous amounts of waste heat. Just take a look at a picture of any nuke plant - the largest, most recognizable features aren't the containment - it's the cooling towers. Nuclear reactors are VERY inefficient at converting atomic energy into electrical energy, and generate huge amounts of waste heat. Wind and hydro power create dramatically less "waste heat".

Even solar power (which, at 10% efficiency, generates about 90% "waste heat") doesn't generate as much "waste heat", since sunlight not used to generate power creates almost 100% "waste heat".

Nuclear Power is a matter of hubris - an attempt to prove that we have mastered nature, rather than accepting that nature will always be the master of us.

 

[Belisarius]

Agree totally with Tommy, especially with his diagnosis of hubris. Urwumpe quoted a poem a few days ago that expresses that same idea very strongly.

Meanwhile, the Daily Telegraph in the UK found leaked material of a secret IAEA meeting in 2008 from the WikiLeaks diplomatic cables cache.

On earthquakes and nuclear safety, the IAEA presenter noted the Agency has officials in Japan to learn from Japan's recent experience dealing with earthquakes and described several areas of IAEA focus. First, he explained that safety guides for seismic safety have only been revised three times in the last 35 years and that the IAEA is now reexamining them. Also, the presenter noted recent earthquakes in some cases have exceeded the design basis for some nuclear plants, and that this a serious problem that is now driving seismic safety work. The IAEA is issuing a new guide on seismic evaluation to accompany existing guidelines on seismic hazard and design. Finally, the IAEA noted it had launched an International Seismic Safety Center at its September general conference to enhance safety, develop standards, pool and share knowledge.

http://www.telegraph.co.uk/news/wik...CEMBER-NUCLEAR-SAFETY-AND-SECURITY-GROUP.html

Thanks for this information go to PFC Bradley Manning and Julian Assange, both now in jail awaiting trial for their offences.
CORRECTION: Of course Assange isn't in jail yet, he is awaiting appeal in the UK for his extradition to Sweden. Sorry for this mistake.

 

[Tommy]

Thanks for this information go to PFC Bradley Manning and Julian Assange, both now in jail awaiting trial for their offences.

I consider PFC Manning to be a true patriot, who understands that the people have rights - and governments have only privileges. Since Julian isn't a US citizen, I guess he doesn't qualify as a patriot - but I admire and respect him greatly.

 

[Sky Captain]

Best soulution to nuclear waste would be to turn it into energy in a breeder reactor. Even if right now all nuclear reactors were shut down their spent fuel will remain, it won't magically go away because Greenpeace screams nuclear power is bad. An efficient breeder reactor could burn up most of transuranic elements and uranium238 that make up most of the spent fuel leaving only fission products which would recquire special storage only few hundred years vs thousands of years like spent fuel from currently used reactors. There are enough spent fuel and already mined uranium238 in storage that most of the worlds energy needs could be met for decades without any additional uranium mining. It would be a win win solution - most of nuclear waste recquiring long term storage consumed and large amounts of energy generated in the process.

---------- Post added at 07:12 PM ---------- Previous post was at 06:57 PM ----------

There are also pump power plants, which pump water upwards during times of excessive power, and let this water run through turbines when there is a higher demand. Such pumps are already used today for reacting to short term demands and cause less ecologic damage since they require no natural water flow to be obstructed.

There are also battery storages, which can power a whole quarter in a city for days, but these are still a bit expensive (But much more effective as pumps).

That is certainly possible, but how it can be accomplished without making electricity more expensive? For example wind generators have 20 - 30 % capacity factor so you need to install ~4 times as much capacity as in case of coal or nuclear power plant. In addition to that you have to build pumped storage plants on a huge scale to supply power when wind goes down. That is huge capital investment.

---------- Post added at 07:20 PM ---------- Previous post was at 07:12 PM ----------

1: Here in the US, there are over 35,000 "flood control" dams. These dams are used to regulate rivers and prevent floods - and none of them are used to generate power.

How is that possible? Hydropower is very cheap to produce and unlike sun or wind it is available of demand. and if there already is dam built then most of the capital costs are paid by someone else, it would be cheaper to retrofit an existing dam to generate power than building a new nuclear or fossil plant. I guess there again is some sort of beurocratic obstacle that makes it hard to do

 

[Urwumpe]

B
That is certainly possible, but how it can be accomplished without making electricity more expensive?

Very simply: Not. Forget the idea that energy could be made cheaper by now. Even if we would get working fusion power plants, the energy would be more expensive.

As long as energy companies get a large amount of the costs paid by the tax payer indirectly, energy is cheap. You pay essentially with your taxes that large factories get really cheap energy.

If I calculate correctly, the taxes that we pay every year that go into the energy companies, mean essentially 15% higher costs for electricity at the source. No change for the electricity costs for us: about 80% of the price you pay for electricity ends as raw profits at the energy companies. or why do you think, are three German energy companies among the top ten energy producers of the whole world in terms of capital and revenue?

You want to pay less for energy in the future? Learn saving energy. And get better in it. But don't get too good at it, unless you want to ruin the energy companies more:

If all Germany would suddenly consume 10% less electricity, one third of all nuclear power plants would need to be shut down instantly, because they can't be operated. It is very hard to run a nuclear reactor at just 50% rated power.

 

[Turbinator]

France is on the right track with a deuterium powered tokamak nuclear fusion reactor, [ame="http://en.wikipedia.org/wiki/ITER"]ITER - Wikipedia, the free encyclopedia[/ame]

We are already at a level where we can generate more power with nuclear fusion than we put in to it, generating a net gain.

 

[Belisarius]

I know that most of the contamination problems are solved in fusion, but what about safety issues?
Couldn't a catastrophic shock equally breach a fusion reactor and allow a stream of radioactive plasma to come shooting out?

 

[Urwumpe]

I know that most of the contamination problems are solved in fusion, but what about safety issues?
Couldn't a catastrophic shock equally breach a fusion reactor and allow a stream of radioactive plasma to come shooting out?

Yes, but we are talking then of completely different masses.

A nuclear fission fuel element is 4% actual fission fuel, and a reactor carries a few tons of fuel elements. This fuel lasts for about 2 years until the amount of fuel in the fuel element is too low for being useful (about 1% fuel left). Only a small amount of uranium is actually producing energy at a time.

In a fusion reactor, you will maximal have grams of plasma in it, for producing the same energy. Even if the containment will breach, the actual radioactivity of the fuel in it is less, the machinery (Tokamak torus vs Reactor Pressure Vessel) will weight about the same and be a bit less radioactive.

 

[Linguofreak]

I know that most of the contamination problems are solved in fusion, but what about safety issues?
Couldn't a catastrophic shock equally breach a fusion reactor and allow a stream of radioactive plasma to come shooting out?

Well, for one thing, AFAIK, it wouldn't exactly come "shooting out". I believe the containment vessel in a fusion reactor is generally kept at lower than atmospheric pressure, so a breach would lead to air being sucked into the containment vessel before anything leaked out.

Furthermore, both the reactants and the products are much less radioactive than those involved in fission, so most of the radiation would be from the reaction itself. Anything within line-of-sight of the plasma through the breach at the moment that the breach occured would probably get a heightened radiation dose, but I'm pretty sure this would be stopped fairly quickly as the inrushing air killed the reaction. It certainly wouldn't be a danger to anything off-site, and most likely not to anything outside of the same room.

 

[T.Neo]

Doesn't tritium need to be produced in a special sort of fission reactor?

If so, why wouldn't it be more efficient (energy or money wise) just to use fission reactors? Or do the safety/waste advantages of fusion outweigh this?

 

[Tommy]

He3 can be used in some reactor designs, such as the Polywell, IIRC, and is quite abundant on the Moon.

While the initial cost of setting up a surface mining, a reactor, and a rail gun (to launch cargo to Earth) would be expensive, it's not out of reach of existing technology (at least once the fusion reactors are a bit more efficient)

 

[Sky Captain]

If looking at various energy sources from the potential to cause greatest loss of life and general destruction then hydropower comes out on the top. For example
[ame="http://en.wikipedia.org/wiki/Shimantan_Dam"]Banqiao Dam - Wikipedia, the free encyclopedia[/ame]

26 000 dead immediatly, 145 000 from aftereffects and 11 million made homeless and all of that from failures of several relaively minor dams. No nuclear accident comes even close. Now imagine what would happen if Aswan dam failed catastrophically. I guess Egypt likely would cease to exist as a country since most of it would be washed into Mediterranean sea.

 

[T.Neo]

He3 can be used in some reactor designs, such as the Polywell, IIRC, and is quite abundant on the Moon.

While the initial cost of setting up a surface mining, a reactor, and a rail gun (to launch cargo to Earth) would be expensive, it's not out of reach of existing technology (at least once the fusion reactors are a bit more efficient)

"Abundant on the Moon" is unfortunately not an easy solution... it is a problem, but maybe a fun one for spaceflight enthusiasts.

From a post I made in a discussion about mining the Moon;

Apollo retrieved 382 kilograms of lunar material. Apollo cost was estimated in 2005 as 170 billion USD (at 2005 inflation rates). The cost/kg of gold at the time of posting is $43 970. If Apollo retrieved 382 kg of pure gold, it would have recouped less than a ten-thousandth of it's total cost.

Let's make it a bit better. Halve the cost, quadruple the return payload. $85 billion cost, 1528 kg of gold returned. Less than a thousandth the total cost. Again, not economically viable whatsoever.

Now, I know everyone is going to say, Apollo was 1960s, it wasn't optimised for returning materials to the moon, etc etc. But the fact is that it doesn't matter, because you're not going to find pure gold on the Moon. Or pure uranium, or pure platinum, or pure anything for that matter. You're going to have to mine and refine whatever you want, and that is going to require a huge amount of technology.

In the entire human history of spaceflight, we have only introduced about 178.8 tons of manmade material to the Moon- a good portion of which is intentionally crashed rocket stages, and low-mass unmanned probes. So much for launching the gigantic mine and refining plant.

Helium 3? It is only found in concentrations of 0.01 ppm in sunlight areas, and 0.05 ppm in shaded ones. So you again run into the mining and refining problem.

Let's say, we want to power a fourth of the world's energy needs on Helium 3 (a power production of 4 terawatts). Helium 3-deuterium fusion has an energy density of (if my math is correct) 350 877 000 MJ/kg. Let's say the fusion reactor(s) have an efficiency of 30%...

This means you need to return 1.2 million kilograms, or 1 200 tons, to Earth, every year. If the return payloads are monthly, that is 100 tons being returned to Earth. A lunar vehicle, not to mention a reentry vehicle, that can carry 100 tons, would be a major feat. And yes, glass cubes launched by a gigantic mass driver... it is a nice idea, but it has many problems.

Furthermore, since you only have 0.01 ppm in most regions, you need to sift through over 300 tons of regolith a day. Which is an absolutely huge, infrastructure. Especially on the Moon.

As for the railgun... it would need huge infrastructure. If you launch often you can reduce payload size, but then you will be... launching often. Which comes with other problems.

It would need a power source, it'd most probably weigh far too much to launch from Earth, so it'd have to be manufactured from in-situ materials... which would require a mine, and a refining plant for various different materials, and they would require power sources, etc. Nobody has yet built any railgun on such a scale either.

And the payloads would also need their own manouvering propellant, their landings would have to be controlled correctly...