Nuclear energy: for or against?

[nikkkom]

I am not seriously proposing that US should be completely switched to solar power. I think we need to use a mix of generation technologies, _including nuclear_.

I responded to argument that "renewables aren't competitive", which is not true.

 

[jim hardy]

I think we need to use a mix of generation technologies, _including nuclear_.

I completely agree.

 

[atyy]

It's unfortunate we have not heard more about the latest generation of nuclear reactors - pebble bed reactors. They are immune to nightmarish melt down scenarios, inexpensive to build and scalable. They can be safely located near heavy demand areas, occupy little real estate, and are highly efficient.

How close to a heavy demand area can it be located? Could it be put in a residential area? Has anyone built one yet?

 

[russ_watters]

How close to a heavy demand area can it be located? Could it be put in a residential area?

I don't see how those are relevant questions: nuclear power plants are already located in residential areas and near major cities. I live near Limerick (Pa) station, which is in a well populated suburb of Philly.

 

[mheslep]

PV costs: "For large-scale installations, prices below $1.00/watt were achieved. A module price of 0.60 Euro/watt ($0.78/watt) was published for a large scale 5-year deal in April 2012."

The *installed* cost of solar power has been slower to drop and resides several times higher than $1/Watt. That is, the price of the panels themselves could go to zero and after installation solar would still be marginally competitive with the cheapest traditional sources.

And the above still does not include the cost of any backup system to include the cost of keeping some gas fired electric plant ready but idle while solar power is performing.

 

[nikkkom]

It's unfortunate we have not heard more about the latest generation of nuclear reactors - pebble bed reactors. They are immune to nightmarish melt down scenarios

Pebble bed reactors are not immune to meltdowns.
To be significantly more resistant to meltdowns than current reactors, reactor needs to continually get rid of fission products (what LFTRs are planning to do).

inexpensive to build

Remains to be seen...

 

[atyy]

I don't see how those are relevant questions: nuclear power plants are already located in residential areas and near major cities. I live near Limerick (Pa) station, which is in a well populated suburb of Philly.

What then was Chronos referring to when he mentioned pebble bed reactors being sited near heavy demand areas as an advantage?

 

[russ_watters]

What then was Chronos referring to when he mentioned pebble bed reactors being sited near heavy demand areas as an advantage?

Dunno, could be a political issue.

 

[Thermalne]

Pebble bed reactors are not immune to meltdowns.
To be significantly more resistant to meltdowns than current reactors, reactor needs to continually get rid of fission products (what LFTRs are planning to do).



Remains to be seen...

The point is... there are many Gen4 or "innovative" designs that have pros and cons that would be useful to use for various reasons. We should build a mixture of reactors (except anything with a positive reactivity coefficient) that are more passively safe than current light water reactors (They are still really freaking safe). Also, there are plenty of ways to make light water reactors passively safe (and not dependent on offsite or onsite power to cool the reactor) and that's how futures ones should be built.

Also, Pebble Bed reactors are cool, but so are molten salt and liquid metal reactors and high temperature gas reactors too!

Also relevant: http://nuclearstreet.com/nuclear_po...e-technology-for-doe-funding-opportunity.aspx

 

[RobinSky]

This might be a retarded question, if so please forgive me I have no knowledge in nuclear physics.
But is it possible to use the nuclear waste as some kind of fuel? If not, is it impossible due to laws of physics or just mainly due to impractical reasons? For me as a novice, the radiation from the nuclear waste is radiating energy, and if it was possible to use that radiation as some kind of fuel, it would be a cool idea.

Thanks in advance.

 

[Thermalne]

This might be a retarded question, if so please forgive me I have no knowledge in nuclear physics.
But is it possible to use the nuclear waste as some kind of fuel? If not, is it impossible due to laws of physics or just mainly due to impractical reasons? For me as a novice, the radiation from the nuclear waste is radiating energy, and if it was possible to use that radiation as some kind of fuel, it would be a cool idea.

Thanks in advance.

Most nuclear "waste" (i.e. used fuel) has only had about 2-3% its potential energy used. Fuel recycling (France does this) and some reactor designs use or recycle previously used fuel.

See: http://www.world-nuclear.org/info/Nuclear-Fuel-Cycle/Fuel-Recycling/Processing-of-Used-Nuclear-Fuel/#.UfWG9Y1kxJQ and http://www.nei.org/Key-Issues/Nuclear-Waste-Disposal/Recycling-Used-Nuclear-Fuel

Very good question. I'm glad you asked.

 

[RobinSky]

Most nuclear "waste" (i.e. used fuel) has only had about 2-3% its potential energy used. Fuel recycling (France does this) and some reactor designs use or recycle previously used fuel.

See: http://www.world-nuclear.org/info/Nuclear-Fuel-Cycle/Fuel-Recycling/Processing-of-Used-Nuclear-Fuel/#.UfWG9Y1kxJQ and http://www.nei.org/Key-Issues/Nuclear-Waste-Disposal/Recycling-Used-Nuclear-Fuel

Very good question. I'm glad you asked.

Cool, thanks for the good links! I had no idea about this, and that so little energy is used of the fuel really suprised me. Is there any limit set by nature from the energy we can get from our nuclear fuel? Something like Bet'z law but for nuclear fuel.

/Robin

 

[BruceW]

I think that Iron is the lightest element that you could keep doing fission on to get energy (in a theoretical sense). For lighter elements, if you continue to do fission, you have to put in more energy than you get out. So in principle, you could do fission repeatedly on some nuclear fuel (and its daughter atoms), until you are left with Iron. But of course, there are reasons that we do not do this. I guess you could call them 'practicality reasons'. http://en.wikipedia.org/wiki/Fissile

 

[RobinSky]

But what limits us from not "extracting" more than just 2-3% of the energy? Is it limits set by nature or are the reasons because it's hard with current technology? This is very interesting!

 

[gmax137]

Many of the fission products are good neutron absorbers. With time the fission products build up and absorb more and more neutrons. So, there are fewer and fewer neutrons available to maintain the chain reaction.

You could take the fuel out of the core and process the material to remove the fission products and then re-use the uranium to make new fuel. This "re-processing" is not done here in the US.

 

[BruceW]

But what limits us from not "extracting" more than just 2-3% of the energy? Is it limits set by nature or are the reasons because it's hard with current technology? This is very interesting!

It is hard with current technology. Given the right conditions, fission of lighter elements could produce heat. But making those conditions would probably cost more. Remember that we are here on earth, which is a certain temperature and pressure, and with a certain proportion of elements.

 

[African Rover]

I am not seriously proposing that US should be completely switched to solar power. I think we need to use a mix of generation technologies, _including nuclear_.

I responded to argument that "renewables aren't competitive", which is not true.

I think renewables are not competitive. Germans have to pay a levy of more than 6 cents (Euro)per kWh, just to support renewables. Canadians produce nuclear electricity for about half that amount.
Solar power is particularly expensive. The cost per kW is irrelevant, count the cost per kWh. Add the cost of a storage system and, or, add the cost of a backup power plant. Why build a renewable power plant if you have to back it up anyway with a conventional power plant? The electricity storage system that is really proven is the pumped storage scheme. But you need the space and the right geology for that. The damage to the environment is about the same as strip mining.
At the moment the U.K. is set to pay about 90-95 pounds per MWh for new nuclear energy. But for wind they are paying 130 pounds.
If you have an insight as to how that makes renewables cheaper please let me know.

 

[African Rover]

that's why they oppose fission and fusion?!? You mean that they are worried their funding will be given to nuclear power projects instead?

Not quite, environmentalists are funded by the oil and gas lobby.

 

[nikkkom]

Solar power is particularly expensive. The cost per kW is irrelevant, count the cost per kWh.

Keep saying that, maybe you will even start believing it.
Market data says otherwise.

Solar power's cost goes down 20% with each doubling of production capacity. And the production capacity is nowhere near market saturation. Ergo, solar cells are going to become more than twice as cheap at today.

BTW, got any plans how to stop those pesky engineers from finding ways to manufacture cheaper and/or more efficient solar cells?

Add the cost of a storage system and, or, add the cost of a backup power plant.

In Sahara, you hardly ever need a backup.

 

[etudiant]

Keep saying that, maybe you will even start believing it.
Market data says otherwise.

Solar power's cost goes down 20% with each doubling of production capacity. And the production capacity is nowhere near market saturation. Ergo, solar cells are going to become more than twice as cheap at today.

BTW, got any plans how to stop those pesky engineers from finding ways to manufacture cheaper and/or more efficient solar cells?



In Sahara, you hardly ever need a backup.

Nighttime is an issue, even in the Sahara. Backup remains essential.
Also, the steady decline in solar panel prices has not been mirrored by similar declines in installation and integration costs, so the overall improvements are much slower.
Still, I agree that solar has much more potential than wind turbines, huge contraptions stuffed with ultra precision mechanical parts that are about as durable as one would expect them to be.
When the subsidies run out, the turbines will break down long before the solar systems.

 

[nikkkom]

Nighttime is an issue, even in the Sahara.

Nighttime is not a peak load time.

 

[jadair1]

I think renewables are not competitive. Germans have to pay a levy of more than 6 cents (Euro)per kWh, just to support renewables. Canadians produce nuclear electricity for about half that amount.
Solar power is particularly expensive. The cost per kW is irrelevant, count the cost per kWh. Add the cost of a storage system and, or, add the cost of a backup power plant. Why build a renewable power plant if you have to back it up anyway with a conventional power plant? The electricity storage system that is really proven is the pumped storage scheme. But you need the space and the right geology for that. The damage to the environment is about the same as strip mining.
At the moment the U.K. is set to pay about 90-95 pounds per MWh for new nuclear energy. But for wind they are paying 130 pounds.
If you have an insight as to how that makes renewables cheaper please let me know.

A question, how long does it take to decommisson a Nuclear Plant after it is permantely shut down?

Let's use the San Onofre or Vermont Yankee NPP's as examples.

How long will the spent fuel need to be cooled and how much energy will that take?

What will it cost to store the radioactive waste for the thousands of years it will be dangerous?

How radioactive are the containment vessels etc and what will it cost to decontaminate them and disasemble them or do we just let them sit there for hundreds of thousands of years? In Canada we allow the facility to be placed in "safe storage" so no work needs to be done for 50 years or more after shutdown.

I believe the promise of Nuclear energy being "to cheap to meter" when it was first proposed did not take any of these things into account.

If these costs are factored into the price of the power I think Nuclear Power is to expensive to produce without massive government subsides and that doesn't even factor in the economic cost of a Chernoble or Fukushima type disaster!

I used to be a proponent of nuclear power but I am no longer, I have gone to the dark side.

 

[gmax137]

... The cost per kW is irrelevant, count the cost per kWh ...

Of course it is relevant. Otherwise your very next words make no sense:

... Add the cost of a storage system and, or, add the cost of a backup power plant. Why build a renewable power plant if you have to back it up anyway with a conventional power plant?

...
I believe the promise of Nuclear energy being "to cheap to meter" when it was first proposed did not take any of these things into account.

You might want to look into the source of that quote more closely. Lewis Strauss (a business man and AEC commissioner) was talking about fusion.
https://en.wikipedia.org/wiki/Lewis_Strauss
A hundred years from now, people may be using that quote as an example of brilliant foresight ("they laughed at Strauss..."). Or maybe not. The point is, it had nothing to do with fission technology.

... If these costs are factored into the price of the power I think Nuclear Power is to expensive to produce without massive government subsides ...

Actually, those costs are taken into account, at least in the US.

And, what massive subsidies are you thinking about? Today the massive subsidies go to oil & gas, and renewables. In the 1980s - 1990s - 2000s they went to oil & gas, in the 1960s they went to oil & gas and nuclear. Do you see a pattern there?

And how do you account for the subsidy coal burning gets? We allow them to put their waste into the air we breathe. If nuclear was allowed to do that, it wouldn't have "a waste problem" either.

 

[African Rover]

In Sahara, you hardly ever need a backup.[/QUOTE]

Trust me, I traveled through it more than once, the Sahara is not in the land of the midnight sun.
No matter what time of the year it is, latest at 19.30h the sun is gone and it is dark, and in winter the temperatures drop below freezing in many areas within half an hour after sunset. I think you would want a storage or backup then.

 

[jadair1]

Of course it is relevant. Otherwise your very next words make no sense:





You might want to look into the source of that quote more closely. Lewis Strauss (a business man and AEC commissioner) was talking about fusion.
https://en.wikipedia.org/wiki/Lewis_Strauss
A hundred years from now, people may be using that quote as an example of brilliant foresight ("they laughed at Strauss..."). Or maybe not. The point is, it had nothing to do with fission technology.




Actually, those costs are taken into account, at least in the US.

And, what massive subsidies are you thinking about? Today the massive subsidies go to oil & gas, and renewables. In the 1980s - 1990s - 2000s they went to oil & gas, in the 1960s they went to oil & gas and nuclear. Do you see a pattern there?

And how do you account for the subsidy coal burning gets? We allow them to put their waste into the air we breathe. If nuclear was allowed to do that, it wouldn't have "a waste problem" either.

Very good points about all energy soures being subsidized.

I don't think the storage and decommissioning costs are fully accounted for, yes in the design stage they are accounted for but I think the real cost are vastly understated. No different from the enviromental damage done by Fracking, deep water drilling , see BP Deewater Horizon, the tar sands or other mining operations.

The real costs are passed on to future taxpayers.

Is it possible that the cost to clean up Fukushima will be greater than all the income generated by all the NPP's in Japan combined?

I am hearing that no insurers /reinsures will underwrite new Plants without liability restrictions.

If Tepco had to pay for all the costs post Fukushima they would be completely bankrupt.

 

[QuantumPion]

Very good points about all energy soures being subsidized.

I don't think the storage and decommissioning costs are fully accounted for, yes in the design stage they are accounted for but I think the real cost are vastly understated. No different from the enviromental damage done by Fracking, deep water drilling , see BP Deewater Horizon, the tar sands or other mining operations.

The real costs are passed on to future taxpayers.

Is it possible that the cost to clean up Fukushima will be greater than all the income generated by all the NPP's in Japan combined?

I am hearing that no insurers /reinsures will underwrite new Plants without liability restrictions.

If Tepco had to pay for all the costs post Fukushima they would be completely bankrupt.

Storage and decommissioning costs are fully accounted for, by law, into a fund paid for by the plant owner. The costs are paid for by electricity customers and company investors, as is the case with all other power sources. Surely you don't believe the enormous subsidies granted to wind and solar (in terms of dollars AND favorable regulations) are not eventually borne out by the public as well?

 

[jadair1]

Storage and decommissioning costs are fully accounted for, by law, into a fund paid for by the plant owner. The costs are paid for by electricity customers and company investors, as is the case with all other power sources. Surely you don't believe the enormous subsidies granted to wind and solar (in terms of dollars AND favorable regulations) are not eventually borne out by the public as well?

Oh give me a break of course I know all energy sources are subsidized. But none more so than Nuclear with the Price-Anderson Act.

It will cost trillions of US Dollars to clean up Fukashima, if it can be done.

What happens if Indian Point melts down and explodes as Fukashima did, yes I know the probability is small, but what if?

It is only 38 miles from NYC, what would be the cost of that? It would be astronomical, Fukushima would be like a pimple on a pigs butt compared to that.

We really need Fusion power, it is the only possible clean energy, all those enviromentalists touting green power such as solar ignore the mining for rare Earth elements neccesary to build them.

Last I heard a few years ago the Tokamak Fusion Reactor was almost net energy efficient.

Interesting, I just read up on Fusion reactors and they say we could be 30 or 40 years away from commercial production.

 

[nikkkom]

We really need Fusion power, it is the only possible clean energy, all those enviromentalists touting green power such as solar ignore the mining for rare Earth elements neccesary to build them.

Amazing depth of economical analysis.
Fusion plans don't need rare Earth metals, right?

 

[Thermalne]

Oh give me a break of course I know all energy sources are subsidized. But none more so than Nuclear with the Price-Anderson Act.

It will cost trillions of US Dollars to clean up Fukashima, if it can be done.

What happens if Indian Point melts down and explodes as Fukashima did, yes I know the probability is small, but what if?

It is only 38 miles from NYC, what would be the cost of that? It would be astronomical, Fukushima would be like a pimple on a pigs butt compared to that.

We really need Fusion power, it is the only possible clean energy, all those enviromentalists touting green power such as solar ignore the mining for rare Earth elements neccesary to build them.

Last I heard a few years ago the Tokamak Fusion Reactor was almost net energy efficient.

Interesting, I just read up on Fusion reactors and they say we could be 30 or 40 years away from commercial production.

Do you have any sources for this information? Otherwise you sound like any other anti-nuke.

 

[etudiant]

My guess is that the Price Anderson liability cover has done more to impede nuclear power than any other single factor.
If liability had been a central concern for the industry, it would never have embraced the thinly modified military reactor technology that is the basis of the current reactor designs, nor the absurd product customization that is the bane of economic production and learning curve improvement.
There were more forgiving alternatives, the General Atomics gas cooled designs for example or the concept of multiple small reactors, but they were never given adequate engineering support to become mainstream.

On a separate note, it is somewhat inconsistent imho to wax indignant about the dreadful threat of radiation pollution from spent nuclear fuel while ignoring the massive environmental damage done by coal mining and the concomitant extensive and near eternal mercury and thorium pollution created by the emissions from these facilities.

 

[jadair1]

Amazing depth of economical analysis.
Fusion plans don't need rare Earth metals, right?

Darn, I competely ignored that fact! Nor did I consider the cost of decomissioning and storing the plants as they became too radioactive to operate.

I've always considered Fusion as the holy grail of energy production.

 

[Thermalne]

Darn, I competely ignored that fact! Nor did I consider the cost of decomissioning and storing the plants as they became too radioactive to operate.

I've always considered Fusion as the holy grail of energy production.

Except that's not the reason why they decommission plants. They decommission end of life plants from the components reaching the end of their usefulness in regards to structural integrity and dropping in efficiency. They same reason why they decommission coal or natural gas or any other type of plant. You need to start looking things up before you start talking about it. I'd recommend http://world-nuclear.org/, http://nuclearliteracy.org/, and http://www.iaea.org/ as starter resources.

(I'll acknowlegde that other factors do play into the decision to decommission a generic power plant, but a nuclear power plant is not decommissioned for being "too" radioactive.")

 

[jadair1]

Do you have any sources for this information? Otherwise you sound like any other anti-nuke.

None that you would believe, but it has been reported Gorbachev stating that the cost of Chernobyl was responsible for the fall of the Soviet Union. I do not know if that is true or not.

It has been two and a half years since the triple meltdown at Fukushima and has anybody gone into inspect the conditions inside reactors 1 to 3, can they?

How much has it cost to date for the minimal work they have done and how much will it cost over the next 40, 50 years or more to clean this mess up?

Yes I am just another anti-nuke, funny even after Three Mile Island and Chernobyl I was staunchly pro nuke but Fukashima has turned me to the dark side!

 

[etudiant]

The Japanese have somewhere around 5000 workers at Fukushima and the long term plans are for about a 30-50 year clean up effort. So assuming at least 3 support people for every guy on the front line, about 20,000 man years for 50 years, or about a million man years at probably $200,000/man year fully loaded cost.
So about $200 billion plus equipment costs, maybe another $100 billion at a rough guess.
That puts the eventual cost at about a third of a trillion, or about half a months GNP for Japan equivalent, spread over 50 years.
It is a disaster, but on a much lesser scale than the USs housing bubble for example, which was perhaps 10 times bigger and wrecked many more lives.

 

[jadair1]

From Wikapedia

"Even if these goals are met, there are a number of major engineering problems remaining, notably finding suitable "low activity" materials for reactor construction, demonstrating secondary systems including practical tritium extraction, and building reactor designs that allow their reactor core to be removed when its materials becomes embrittled due to the neutron flux"

Also:

"Developing materials for fusion reactors has long been recognized as a problem nearly as difficult and important as that of plasma confinement, but it has received only a fraction of the attention. The neutron flux in a fusion reactor is expected to be about 100 times that in existing pressurized water reactors (PWR). Each atom in the blanket of a fusion reactor is expected to be hit by a neutron and displaced about a hundred times before the material is replaced. Furthermore the high-energy neutrons will produce hydrogen and helium by way of various nuclear reactions that tends to form bubbles at grain boundaries and result in swelling, blistering or embrittlement. There is also a need for materials whose primary components and impurities do not result in long-lived radioactive wastes. Finally, the mechanical forces and temperatures are large, and there may be frequent cycling of both".

Also this:

"Carbon[edit]If graphite is used, the gross erosion rates due to physical and chemical sputtering would be many meters per year, so one must rely on redeposition of the sputtered material. The location of the redeposition will not exactly coincide with the location of the sputtering, so one is still left with erosion rates that may be prohibitive. An even larger problem is the tritium co-deposited with the redeposited graphite. The tritium inventory in graphite layers and dust in a reactor could quickly build up to many kilograms, representing a waste of resources and a serious radiological hazard in case of an accident. The consensus of the fusion community seems to be that graphite, although a very attractive material for fusion experiments, cannot be the primary PFC material in a commercial reactor.

Tungsten[edit]The sputtering rate of tungsten can be orders of magnitude smaller than that of carbon, and tritium is not so easily incorporated into redeposited tungsten, making this a more attractive choice. On the other hand, tungsten impurities in a plasma are much more damaging than carbon impurities, and self-sputtering of tungsten can be high, so it will be necessary to ensure that the plasma in contact with the tungsten is not too hot (a few tens of eV rather than hundreds of eV). Tungsten also has disadvantages in terms of eddy currents and melting in off-normal events, as well as some radiological issues.[1]"

Someone here last night sugested I check Wikipedia for information, so I did.