Safe Storage of Nuclear Waste

[vanesch]

But it seems that quite a few actinides are found naturally in the Earth. Then don't most actinides share some common components.Why can't they be dumped deep into the Earth, of course, in a depth which is safely above the water -table?

Deep means "below the water table". So deep repositories are necessarily wet, but this is not a bad thing. Because "below the water table" also means "saturated" and hence no oxygen: the environment is chemically reducing. This is a major contributor to stopping the migration of actinides and many other metal ions, which will not be soluble in a reducing water environment. The downside of the wet part is of course the slow corrosion of the stainless steel, and the solution of the glass matrix.

The only repository above the water table I know of is the Yucca Mountain, but it is not considered to be the best of repositories (although it might do its thing).

There is a totally different repository which has been studied, and that was: deep ocean sediments. A very complete study was performed outside of the coast of Hawaii. The idea was to have "penetrator" containers which sink to the bottom and penetrate a few tens of meters into the sediments (which are highly binding also for actinides). The soil there is geologically extremely stable, and the sediments will build up over the years, hence burying the waste deeper and deeper. An eventual leak in the far future would be diluted immediately in the ocean, and no ground water or any people would ever suffer from any increased exposure. Moreover, the technique is very cheap. All considerations of access to the waste for terrorist purposes or whatever are of course totally moot in this context.
However, the project was canceled for unclear political reasons.

 

[Azael]

Deep means "below the water table". So deep repositories are necessarily wet, but this is not a bad thing. Because "below the water table" also means "saturated" and hence no oxygen: the environment is chemically reducing. This is a major contributor to stopping the migration of actinides and many other metal ions, which will not be soluble in a reducing water environment. The downside of the wet part is of course the slow corrosion of the stainless steel, and the solution of the glass matrix.

The only repository above the water table I know of is the Yucca Mountain, but it is not considered to be the best of repositories (although it might do its thing).

There is a totally different repository which has been studied, and that was: deep ocean sediments. A very complete study was performed outside of the coast of Hawaii. The idea was to have "penetrator" containers which sink to the bottom and penetrate a few tens of meters into the sediments (which are highly binding also for actinides). The soil there is geologically extremely stable, and the sediments will build up over the years, hence burying the waste deeper and deeper. An eventual leak in the far future would be diluted immediately in the ocean, and no ground water or any people would ever suffer from any increased exposure. Moreover, the technique is very cheap. All considerations of access to the waste for terrorist purposes or whatever are of course totally moot in this context.
However, the project was canceled for unclear political reasons.

WIPP is also a dry repository. I honestly don't understand why americans even bother with Yucca mountain when they already have WIPP running?
http://en.wikipedia.org/wiki/WIPP

The main advantage with the deep ocean sediment deposits if I understood it right was also that the maximum diffusion rate of waste through the sediments was lower than the rate of new sediment deposits. So no matter what happens to the canisters the waste would never leak through the sedimentation. Vanesch would you happen to know where the research results of the deep ocean research has been published? I have been trying to find it ever since I read about it in Gwyneth Cravens book.

 

[vanesch]

WIPP is also a dry repository. I honestly don't understand why americans even bother with Yucca mountain when they already have WIPP running?
http://en.wikipedia.org/wiki/WIPP

Well, a salt repository is also a sub-watertable repository, only, the salt has absorbed all of the groundwater present. A similar project (but with much more political resistance) is under examination in Germany (the Gorleben salt dome). The presence of some water is actually necessary in order for the salt rock to tighten up.

But it is true - I heard several experts on this - that Yucca is not really geologically the best kind of solution for a repository. I saw a presentation by a geologist who said that it is ideal as a reversible long term storage facility.

I have been trying to find it ever since I read about it in Gwyneth Cravens book.

I also have this from that book
There is this: http://www.theatlantic.com/issues/96oct/seabed/seabed.htm
I don't know what it is worth. I'm interested too.

 

[Astronuc]

WIPP was primarily for high level waste for the DOE (weapons) program, and the idea of Yucca Mountain was to have a separate facility for civilian (commercial) spent fuel.

Also, the salt in WIPP apparently 'flows', and apparently at a faster rate than was first determined (IIRC).

 

[mheslep]

I don't understand that $14B.

I don't either. I would like to see the cost break out.

The new EPR, which is still in "pilot" stage (no mass production yet, so more expensive), is estimated to cost ~ 3.3B Euro
http://en.wikipedia.org/wiki/European_Pressurized_Reactor
(although the Finnish project will probably be more expensive, mainly for extra regulatory issues - red tape costs). It is a 1.6 GW e plant. So even with a serious cost overrun (say, 50%), and knowing it is still a pilot plant, $14B seems extremely expensive compared to this.

I am not clear what the nuclear / non-nuclear split means here:
http://energies.edf.com/122321i/Acc...-Flamanville-3/the-Flamanville-3-project.html

projected costs and funding
The Flamanville 3 project involves around 3.3 billion Euros of capital expenditure, including EPR development costs. The nuclear part of the facility accounts for 60% of the total amount with the conventional (non-nuclear) part accounting for the rest.

Yes, but *average* doesn't mean: "when needed" ; as such, average erratic power is less than half the price of "available".
Taking the average price equal to the total price can only be the case when wind is "within the noise margin" of power production, as it is in all countries but Denmark. So the marginal cost of wind is relatively low for the first 10-20% of installed wind power, and once it becomes an important component in the network, and starts causing problems because of the fluctuations, costs rise dramatically, because of the need of compensation.

As I said above wind has to be coupled with other forms of power such as pump storage (26GW in the US so far) and perhaps hydrogen from electrolysis and then to gas turbines*. With a widely distributed wind system I don't believe we're looking at that much backup required to have always available power.

*Or power plant scale fuel cells, looks like FCs will arrive there much sooner than vehicles.

 

[mheslep]

Well, I suspect it is pretty good on the facts, it's just the opinions that are suspect. The author seems to have a pretty strong left-wing bias that reflects in his work:
http://web.mit.edu/chemistry/deutch/policy.html

Simply put, the opinion parts of his position seem based on the obsolte/incorrect hippie view of nuclear power. I must admit, I've only read his summery so far - I'll have to read more of his analysis.

Care to specify? The Future of Nuclear Power study has many authors so its hard to credit him w/ specific views found in there. They favor nuclear power but with specific guidelines

I thought I had seen Deutch's name before; didn't realize it was the political/op-ed Deutch. In any case Deutch is just one of many authors of The Future...
Moniz, the co-chair doesn't have any easy to find political views and seems to focus more on energy policy.

PROFESSOR STEPHEN ANSOLABEHERE
Department of Political Science, MIT

PROFESSOR JOHN DEUTCH — CO CHAIR
Department of Chemistry, MIT

PROFESSOR EMERITUS MICHAEL DRISCOLL
Department of Nuclear Engineering, MIT

PROFESSOR PAUL E. GRAY
President Emeritus, MIT
Department of Electrical Engineering and Computer Science

PROFESSOR JOHN P. HOLDREN
Department of Earth and Planetary Sciences, Harvard University.

PROFESSOR PAUL L. JOSKOW
Department of Economics and Sloan School of Management, MIT

PROFESSOR RICHARD K. LESTER
Department of Nuclear Engineering, MIT

PROFESSOR ERNEST J. MONIZ — CO CHAIR
Department of Physics, MIT

PROFESSOR NEIL E. TODREAS
Department of Nuclear Engineering, MIT
Department of Mechanical Engineering, MIT

 

[Astronuc]

The $14 billion for two Westinghouse AP-1000's seems way too high. I would think it closer to $2-3 billion for the pair, and $3 billion seems awfully high for a transmission line, unless they have to obtain a new right-of-way.

EPR is still relatively new, so it is expected that the cost will be high, but it should decrease if more units are built.

With respect to nuclear/convention (or non-nuclear), those may refer to the primary system of which the nuclear reactor is part and the secondary side and balance of plant. Some of the biggest capital expense is for the reactor pressure vessel and steam generators, which are BIG forgings, and the reactor coolant pumps and high pressure piping.

 

[mheslep]

The $14 billion for two Westinghouse AP-1000's seems way too high. I would think it closer to $2-3 billion for the pair, and $3 billion seems awfully high for a transmission line, unless they have to obtain a new right-of-way.

EPR is still relatively new, so it is expected that the cost will be high, but it should decrease if more units are built.

With respect to nuclear/convention (or non-nuclear), those may refer to the primary system of which the nuclear reactor is part and the secondary side and balance of plant. Some of the biggest capital expense is for the reactor pressure vessel and steam generators, which are BIG forgings, and the reactor coolant pumps and high pressure piping.

All of the several new US reactor projects are coming in at very high costs - no less than $5 and up to $14B per today's WSJ. I'll post the details later ...

 

[mheslep]

Here it is, Monday 5/11 WSJ.

New Wave of Nuclear Plants Faces High Costs
http://online.wsj.com/article/SB121055252677483933.html

Byline Rebecca Smith, the journal's energy reporter.

A new generation of nuclear power plants is on the drawing boards in the U.S., but the projected cost is causing some sticker shock: $5 billion to $12 billion a plant, double to quadruple earlier rough estimates.
...
FPL Group, Juno Beach, Fla., estimates it will cost $6 billion to $9 billion to build each of two reactors at its Turkey Point nuclear site in southeast Florida. It has picked a reactor design by Westinghouse Electric Co., a unit of Toshiba Corp., after concluding it could cost as much as $12 billion to build plants with reactors designed by General Electric Co. The joint venture GE Hitachi Nuclear Energy said it hasn't seen FPL's calculations but is confident its units "are cost-competitive compared with other nuclear designs."
...
Exelon, the nation's biggest nuclear operator, is considering building two reactors on an undeveloped site in Texas, and said the cost could be $5 billion to $6.5 billion each.
...
The latest projections follow months of tough negotiations between utility companies and key suppliers, and suggest efforts to control costs are proving elusive. Estimates released in recent weeks by experienced nuclear operators -- NRG Energy Inc., Progress Energy Inc., Exelon Corp., Southern Co. and FPL Group Inc. -- "have blown by our highest estimate" of costs computed just eight months ago, said Jim Hempstead, a senior credit officer at Moody's Investors Service credit-rating agency in New York.

Just a two part explanation: inflation/dollar hits on materials; suppliers and expertise has faded:

Plants are being proposed in a period of skyrocketing costs for commodities such as cement, steel and copper; amid a growing shortage of skilled labor; and against the backdrop of a shrunken supplier network for the industry.

I had thought regulatory hurdles were partly the blame, but not so much:

The price escalation is sobering because the industry and regulators have worked hard to make development more efficient, in hopes of eliminating problems that in the past produced harrowing cost overruns. The Nuclear Regulatory Commission, for example, has created a streamlined licensing process to make timelier, more comprehensive decisions about proposals. Nuclear vendors have developed standardized designs for plants to reduce construction and operating costs. And utility executives, with years of operating experience behind them, are more astute buyers.

 

[mheslep]

Then the US CBO just released its report
"The Role of Nuclear Power in Generating Electricity"
http://www.cbo.gov/ftpdocs/91xx/doc9133/toc.htm

which contains estimates which contradict the actual costs coming in. From the Summary:

Cost of Construction. Historically, construction costs for nuclear facilities have been roughly double initial estimates. NRC’s revised licensing process for nuclear power plants is expected to reduce midconstruction modifications, which were blamed for many cost overruns in the past. Moreover, vendors argue that advanced reactors will have lower construction costs because they have fewer parts than older reactors. As a result, CBO’s base-case assumption for construction costs is about 25 percent lower than the historical average—a figure that reflects recent experience in the construction of advanced reactors in Japan. If those factors turned out not to reduce construction costs in the United States, nuclear capacity would probably be an unattractive investment even with EPAct incentives, unless substantial carbon dioxide charges were imposed.

So why is nuclear construction so much cheaper in Japan?

Details:
http://www.cbo.gov/ftpdocs/91xx/doc9133/Chapter2.5.1.shtml

CBO’s base-case assumptions include overnight costs of about $2.4 million for each megawatt of capacity for new nuclear plants and innovative coal plants but lower costs for conventional coal, conventional natural gas, and innovative natural gas technologies. For nuclear and innovative coal and natural gas technologies, the assumptions are intended to represent plants built over the next decade but do not incorporate the first-of-a-kind costs that are assumed to be covered by federal research and development programs. The estimate for nuclear plants, taken from the EIA’s most recent analysis, is roughly 10 percent above the estimate of overnight costs used in MIT’s study,which was published in 2003,

(That is the MIT study mentioned up thread.)

before construction costs for most types of power plants surged. CBO also calculated construction costs for each technology using alternative assumptions designed to capture plausible variations in those costs. For nuclear and innovative coal technologies, CBO considered construction costs ranging from about $1.2 million per megawatt of capacity to roughly $4.8 million per megawatt of capacity. The breadth of that range reflects the uncertainty associated with the cost of building new nuclear plants in the United States and is wide enough to capture plausible further increases in construction costs, which could affect conventional fossil-fuel plants as well.

Followed up by a caveat on the cost overages in the past:

CBO’s assumption about the cost of building new nuclear power plants in the United States is particularly uncertain because of the industry’s history of construction cost overruns. For the 75 nuclear power plants built in the United States between 1966 and 1986, the average actual cost of construction exceeded the initial estimates by over 200 percent (see Table 2-1). Although no new nuclear power plants were proposed after the partial core meltdown at Three Mile Island in 1979, utilities attempted to complete more than 40 nuclear power projects already under way. For those plants, construction cost overruns exceeded 250 percent.3 (An average of 12 years elapsed between the start of construction and the point at which the plants began commercial operation. The overruns in overnight costs did not include additional financing costs that were attributable to post-accident construction delays.)4

 

[mheslep]

Some of the biggest capital expense is for the reactor pressure vessel and steam generators, which are BIG forgings, and the reactor coolant pumps and high pressure piping.

That would explain some of it. The price of steel has gone up ~3x since 2000, but %40 of that was a spike in just this last month - April to May.
http://www.dot.state.oh.us/construction/oca/Steel_Index_for_PN525.htm

Of course that's going to impact any new construction, just nuclear more than most.

 

[vanesch]

As I said above wind has to be coupled with other forms of power such as pump storage (26GW in the US so far) and perhaps hydrogen from electrolysis and then to gas turbines*. With a widely distributed wind system I don't believe we're looking at that much backup required to have always available power.

*Or power plant scale fuel cells, looks like FCs will arrive there much sooner than vehicles.

My point is: the proof of the pudding is the eating. There are many non-nuclear power countries, or countries which have a high desire to get rid of their nuclear (Germany comes to mind). Their research in alternatives is not recent, but runs already for a few decades. Why haven't we seen these wonderful systems then ? Why are they, when the light threatens to go out, building brown coal plants ?

I'm manifestly pro-nuclear, but not because of some vested interest, but rather because I'm honestly convinced that in the coming 3 or 4 decades at least, they are the only large-scale alternative to coal and gas. I'm not against alternatives, I'm not against wind, at all. I would indeed prefer that wind and solar could provide us with abundant energy. A priori, I like that also more than nuclear. But when you sit down, and crunch a bit some numbers, the vision changes.

Pumping stations are great buffers, but they increase the price of the installation seriously, they need some specific geography, and moreover their capacity is limited. You cannot live on a pumping station full load for a week (or it has to be a very big one). In fact, if you want to provide an entire country with "pumping station capacity" for a week (which is what you need when you rely on wind), you have to imagine that you are going to provide your country with 100% hydro, except for the river input.

If the point is that "in an extended region, the wind always blows *somewhere*", then you need to install the FULL capacity of an entire country several times over: if the wind only blows in the north-east, then there has to be enough wind capacity in the north-east to provide the entire country with electricity. If the next day, it only blows in the south-west, then again, you need to have the full capacity of an entire country a second time in the south-west.

I don't believe that any fuel cell station that has a significant fraction of the capacity of a country will come online in the next few decades.

If it were that simple, it would already have been done on some scale. I'm all for experimenting - it would really be nice if this rosy picture could come true one day, but you cannot yet count on this as a large-scale policy, to drop proven techniques from the list.

Again, it was not the motivation that was missing in some European countries. But they ended up building coal plants again.

It is rather this observation which makes me pro-nuclear. Not vice versa.

 

[mheslep]

My point is: the proof of the pudding is the eating. There are many non-nuclear power countries, or countries which have a high desire to get rid of their nuclear (Germany comes to mind). Their research in alternatives is not recent, but runs already for a few decades. Why haven't we seen these wonderful systems then ? Why are they, when the light threatens to go out, building brown coal plants ?

The proof is in the recent evidence. Wind power has not been cost effective until the last few years with the creation of 30% capacity 1.5MW turbines. That is reflected in the large jumps in installed wind in just the last 2-3 years. The only power source growing anywhere close to as fast as wind is CCGT. The early, subsidized wind installations in the EU were done on hype.

I'm manifestly pro-nuclear, but not because of some vested interest, but rather because I'm honestly convinced that in the coming 3 or 4 decades at least, they are the only large-scale alternative to coal and gas. I'm not against alternatives, I'm not against wind, at all. I would indeed prefer that wind and solar could provide us with abundant energy. A priori, I like that also more than nuclear. But when you sit down, and crunch a bit some numbers, the vision changes.

Pumping stations are great buffers, but they increase the price of the installation seriously,

$1/watt installed here in 2000. All you need is the space and elevation. Still, agree, that has to be added in some backup percentage to the cost of wind (or other renewable) installation.

they need some specific geography, and moreover their capacity is limited. You cannot live on a pumping station full load for a week (or it has to be a very big one). In fact, if you want to provide an entire country with "pumping station capacity" for a week (which is what you need when you rely on wind), you have to imagine that you are going to provide your country with 100% hydro, except for the river input.

If the point is that "in an extended region, the wind always blows *somewhere*", then you need to install the FULL capacity of an entire country several times over: if the wind only blows in the north-east, then there has to be enough wind capacity in the north-east to provide the entire country with electricity. If the next day, it only blows in the south-west, then again, you need to have the full capacity of an entire country a second time in the south-west.

I don't think this is a correct analysis. Assuming for a moment transmission is unlimited, then if the wind is not blowing in 10% of a country, then you only need 10% backup, installed anywhere, and power can flow to the outage area. Then with realistic transmission limitations that backup percentage has to increase, but not I think to multiples of nationwide full capacity.

I don't believe that any fuel cell station that has a significant fraction of the capacity of a country will come online in the next few decades.

Solid Oxide FCs, $0.80/Watt, 49% efficient. 2006
A Practical Fuel-Cell Power Plant
http://www.technologyreview.com/read_article.aspx?id=17644&ch=energy&a=f
10MW demo plants scheduled to come online 2012, construction starts next year:
http://www.netl.doe.gov/publications/proceedings/07/SECA_Workshop/pdf/SECA%20Overview%20-%20Wayne%20Surdoval%2C%20NETL.pdf, slide 8.
As far as I can see the only hold up on these GE systems is the fuel supply, which at the moment is envisioned to be hydrocarbons - gasified coal - keeping that ~clean is a slowdown. If the fuel is electrolyzed clean H then it could start now.

In general I'm also pro nuclear, but I don't see a good crunching of the numbers on the nuclear side for an industry that plans to scale up by 3 or 4x. On looking at the numbers so far, I see nuclear not properly accounting for the risks of proliferation, and more recently its off by some large multipliers in construction costs, at least in the US. At these cost levels ( $6-8/Watt installed) even solar looks reasonable.

 

[vanesch]

The proof is in the recent evidence. Wind power has not been cost effective until the last few years with the creation of 30% capacity 1.5MW turbines. That is reflected in the large jumps in installed wind in just the last 2-3 years. The only power source growing anywhere close to as fast as wind is CCGT. The early, subsidized wind installations in the EU were done on hype.

We'll see. I had a look at a recent project in my own native country, which is a rather modest 300 MW installed / 100 MW estimated average delivery offshore wind farm to be constructed with 60 5 MW units:
http://www.c-power.be/applet_mernu_en/index01_en.htm
It is a to be realized project as of yet, so I would take it to be state of the art.

Price tag: 8 Euros per average delivered W (~ $13,- per average delivered watt): the project is projected to cost 800 million Euro. We don't have any cost overruns yet, as it is still in the project phase.

And one has to say that this farm is going to be placed on a very good, windy place.

You should compare "installed nuclear" with "average wind" because for nuclear, there is a utility factor of over 90%, while for wind, 30% is very optimistic and can only be reached on "good windy places".

If I compare that to an EPR unit, even assuming 50% cost overrun, 3.3 BEuro x 1.5 = 5 B Euro for a 1.6 GW unit, I find 3 Euro per installed (and delivered) Watt, and this adds flexibility to the grid.

That said, I'm all in favor for this kind of constructions. But I refuse to phase out a technology that has proven its utility for a technology that didn't prove - in a real world example, and not a projected scaleup - its capacity to do its thing.

As you correctly point out, it is also ridiculous to think that the world will switch to nuclear. My hope is that renewables and nuclear will both grind away on fossil fuel, and they will meet somewhere when all fossil fuel, or a large part of it, has been replaced by either. The relative fractions will then be settled by the relative capacity of both. I would dream to see 60 or 70 % renewable, but I think that it will stop somewhere around 20 or 30%.

 

[vanesch]

I don't think this is a correct analysis. Assuming for a moment transmission is unlimited, then if the wind is not blowing in 10% of a country, then you only need 10% backup, installed anywhere, and power can flow to the outage area. Then with realistic transmission limitations that backup percentage has to increase, but not I think to multiples of nationwide full capacity.

I was more thinking of a good, blocked anti-cyclone that gives you nice weather and no wind except for a morning and evening breeze for 4 or 5 days over a large portion of a medium-sized country...

 

[Phy6explorer]

What about finding a way to make the waste lose energy by making them emit radiation in the form of particles or electromagnetic waves,that is, do the process of radioactive decay by ourselves?

 

[malawi_glenn]

you mean speed up the process? The radioactive waste is undergoing that prodcess already...

Transmutation is working in that kinda way.

 

[Phy6explorer]

Yes, I am talking about speeding up artificial transmutation to keep pace with the amount of nuclear waste coming in. Natural transmutation is okay, but it takes lot of time and a lot of work to make deep geological repositories and stuff.

 

[malawi_glenn]

Yes, artificial transmutation is under investigation. By bombarding the waste with protons and neutrons, one is hoping for to realease their energy and taking them to a "safer" state. (i.e a shorter lived state)

http://www.neutron.kth.se/courses/transmutation/Chapter1.pdf
http://en.wikipedia.org/wiki/Nuclear_transmutation

 

[Phy6explorer]

I have already checked out the wikipedia link.The first link is very very useful.Thanks a lot!

 

[malawi_glenn]

I have already checked out the wikipedia link.The first link is very very useful.Thanks a lot!

oh, that's great!

It is from a university in the neighbouring town to mine ;)

 

[vanesch]

Yes, I am talking about speeding up artificial transmutation to keep pace with the amount of nuclear waste coming in. Natural transmutation is okay, but it takes lot of time and a lot of work to make deep geological repositories and stuff.

What is under study is the transmutation of minor actinides into fission products (in other words, use them as fuel). This is accomplished in a fast neutron spectrum, which can be obtained in a fast or breeder reactor, or in an ADS (accelerator driven system).

However, there are two caveats to this. Although it makes for great publicity to "reduce the radiotoxicity of the waste from 10000 years to 400 years", there are 2 points:

1) it is absolutely not sure that this can be fully done, with less risk than the extremely small risk these things represent in the future. You need to include extra transportations, extra activities, extra handling today, to avoid a small potential risk in the future and it is not sure you will win. It is also far from sure that you can do this with ALL of the actinides - you might reduce them but are you going to fission 99.9 % of them ?

2) Most repository analyses show that the actinides don't migrate well. So, the tiny dose that one might impose upon a hypothetical future generation by a repository is usually NOT due at all to the actinides.

So the question is: what do we objectively win by transmuting actinides ? And what does it cost us ?

I'm far from convinced that this is a win situation.

 

[vanesch]

Its probably because its almost impossible to produce u-233 without u-232 contamination and u-232 has a very nasty gamma daughter in its decay chain.
http://www.princeton.edu/~globsec/publications/pdf/9_1kang.pdf

Mmm, if I look at the numbers in that paper, and not at the textual arguments, I find U-233 by far the easiest (everything is relative) way to make a bomb.

 

[mheslep]

We'll see. I had a look at a recent project in my own native country, which is a rather modest 300 MW installed / 100 MW estimated average delivery offshore wind farm to be constructed with 60 5 MW units:
http://www.c-power.be/applet_mernu_en/index01_en.htm
It is a to be realized project as of yet, so I would take it to be state of the art.

Price tag: 8 Euros per average delivered W (~ $13,- per average delivered watt): the project is projected to cost 800 million Euro. We don't have any cost overruns yet, as it is still in the project phase.

Curious that a project is going ahead now w/ 5MW units - I had read that the sweet spot in turbine $/W was currently at 1.5MW. Those 5MW units are truly gigantic. The offshore component is apparent in the C-Power project as well. The 142 km of high voltage submarine cable is nearly the same cost as the turbines in Phase I.

And one has to say that this farm is going to be placed on a very good, windy place.

You should compare "installed nuclear" with "average wind" because for nuclear, there is a utility factor of over 90%, while for wind, 30% is very optimistic and can only be reached on "good windy places".

If I compare that to an EPR unit, even assuming 50% cost overrun, 3.3 BEuro x 1.5 = 5 B Euro for a 1.6 GW unit, I find 3 Euro per installed (and delivered) Watt, and this adds flexibility to the grid.

Well I'm suspicious that recent world price spike in materials, esp. steel, is making cost comparisons unreliable unless they are exact contemporaries. I suspect this imminent C-power wind project is reflecting these price hikes and thus only an imminent nuclear project (ala the $14B/2GW Florida plan) would be truly comparable.

 

[vanesch]

Well I'm suspicious that recent world price spike in materials, esp. steel, is making cost comparisons unreliable unless they are exact contemporaries. I suspect this imminent C-power wind project is reflecting these price hikes and thus only an imminent nuclear project (ala the $14B/2GW Florida plan) would be truly comparable.

Well, the Finnish EPR has just started construction, so that is the closest I can come up with (3.3 B Euro and estimated 50% cost overrun).

Actually, a related question is: how does the material bill (steel and concrete) compare between wind and nuclear ? I would think nuclear consumes more material, but is it gigantically more so ?

For the EPR reactor, the pressure vessel contains about 500 tons of steel, and I don't have the numbers for the steam generators, but compared to the N4 French plants, the steam generators are of the same order of magnitude as the pressure vessel (about 20% less, and there are 4 of them), so an estimate would be 2000 tons of steel for an EPR of 1.6 GW electric.

The double containment building, about 55 m high, 2 x 1.3 m thick, and diameter 48 m, must contain about:
3.14 x 48 x 55 x 2.6 = 22 000 m^3 of concrete for the wall, and
2 x 3.14 x 48^2 x 2.6 = 37 000 m^3 of concrete for roof and bottom, so total of 60 000 m^3 concrete.

Now how does that compare to about 1000 5 MW wind turbines (equal average power),
http://www.c-power.be/applet_mernu_en/index01_en.htm
each 120 m high (the tower), with wings 63 meter long each (total height 184 m, 2/3 of the Eiffel tower) ?

Do you do with so much less for one windmill than 2 tons of steel and 60 m^3 of concrete (half a m^3 per meter height) ?

It is my opinion - I can be wrong - that the material investment in steel and concrete of one EPR unit is comparable to the amount of steel and concrete needed for these 1000 turbines.

If that's the case, then material cost is going to have a null-effect on comparisons.

 

[baywax]

What is the attraction about CANDU reactors? As a Canadian I should know but I don't! Are they cheaper, produce less waste or what?

 

[vanesch]

What is the attraction about CANDU reactors? As a Canadian I should know but I don't! Are they cheaper, produce less waste or what?

CANDU reactors are heavy-water moderated and cooled natural uranium reactors.

The main advantage is that they can use natural uranium. As such, they are comparable to the Gen I graphite reactors, but they are a lot safer. They can be loaded and unloaded continuously (that can be seen as an advantage, or a disadvantage, because as such, they are ideal tools to make weapon grade plutonium, or do the thorium - U-233 conversion).

The disadvantage is that they need heavy water, which is expensive to produce (by distillation of ammoniak, I think), and there's another disadvantage connected to the heavy water: they produce loads of tritium (well, that too can be considered an advantage).

Another disadvantage is that they can only moderately "use up" the U-235 in the natural uranium (which can be compensated for by using slightly enriched U, so that the burn-up can be much higher, but then this undoes the main advantage of a CANDU).

 

[mheslep]

What is the attraction about CANDU reactors? As a Canadian I should know but I don't! Are they cheaper, produce less waste or what?

No enrichment required, they work (can) on natural uranium. Either CANDU or NRX reactors (Im not sure which, perhaps both) can then be used to make Pu and give one a path to a bomb and bypass a technologically difficult enrichment program.

 

[baywax]

CANDU reactors are heavy-water moderated and cooled natural uranium reactors.

The main advantage is that they can use natural uranium. As such, they are comparable to the Gen I graphite reactors, but they are a lot safer. They can be loaded and unloaded continuously (that can be seen as an advantage, or a disadvantage, because as such, they are ideal tools to make weapon grade plutonium, or do the thorium - U-233 conversion).

The disadvantage is that they need heavy water, which is expensive to produce (by distillation of ammoniak, I think), and there's another disadvantage connected to the heavy water: they produce loads of tritium (well, that too can be considered an advantage).

Another disadvantage is that they can only moderately "use up" the U-235 in the natural uranium (which can be compensated for by using slightly enriched U, so that the burn-up can be much higher, but then this undoes the main advantage of a CANDU).

Thank you. Theres another reactor in Ontario that was shut down for some reason to do with safety but then a global outcry because it was one of the only reactors that could produce medical grade imaging or treatment grade material. Then the watchdog that shut it down was fired by the Conservative Govt... (like Republicans) and the plant has been re-started... safety issues aside. (?)

 

[baywax]

No enrichment required, they work (can) on natural uranium. Either CANDU or NRX reactors (Im not sure which, perhaps both) can then be used to make Pu and give one a path to a bomb and bypass a technologically difficult enrichment program.

I think we've sold CANDUs to many different countries. Oops.

 

[mheslep]

...If the point is that "in an extended region, the wind always blows *somewhere*", then you need to install the FULL capacity of an entire country several times over:...

I don't believe that any fuel cell station that has a significant fraction of the capacity of a country will come online in the next few decades...

Here's the basic idea at an NREL test facility.
http://www.nrel.gov/hydrogen/proj_wind_hydrogen_animation.html
Wind runs straight to the grid when needed, when its peaking over load it generates H via electrolysis, is pressurized and stored. Fixed plant storage is not that problematic, unlike vehicle storage. Then when needed the H2 drives either and H2 ICE (in low production now) generators or fuel cells.

 

[mheslep]

Well, the Finnish EPR has just started construction, so that is the closest I can come up with (3.3 B Euro and estimated 50% cost overrun).

Yes those are the costs I see, however Olkiluoto started in 2005, they've long since contracted for all their materials.

Actually, a related question is: how does the material bill (steel and concrete) compare between wind and nuclear ? I would think nuclear consumes more material, but is it gigantically more so ?

For the EPR reactor, the pressure vessel contains about 500 tons of steel, and I don't have the numbers for the steam generators, but compared to the N4 French plants, the steam generators are of the same order of magnitude as the pressure vessel (about 20% less, and there are 4 of them), so an estimate would be 2000 tons of steel for an EPR of 1.6 GW electric.

The double containment building, about 55 m high, 2 x 1.3 m thick, and diameter 48 m, must contain about:
3.14 x 48 x 55 x 2.6 = 22 000 m^3 of concrete for the wall, and
2 x 3.14 x 48^2 x 2.6 = 37 000 m^3 of concrete for roof and bottom, so total of 60 000 m^3 concrete.

Plus rebar steel. Strong reinforced concrete about 5% steel by cross section: 60000m^3*0.05=3500m^3; 3500m^3 * 7900kg/m^3 * 907kg/ton = 26000tons rebar steel.

Is the cooling tower significant? Schmehausen, for example: average diameter ~120M, height 180M, 0.1M thick average(?)= 3.14*120*180*0.1 = 6800 m^3 walls
base = 3.15*60^2* 0.2(?) = 2300m^3, total 9000m^3 for the tower. Say 1000tons rebar steel. Not so much compared to that containment bldg. Call it 70,000M^3 concrete, 29000 tons steel, total project.

Now how does that compare to about 1000 5 MW wind turbines (equal average power),
http://www.c-power.be/applet_mernu_en/index01_en.htm
each 120 m high (the tower), with wings 63 meter long each (total height 184 m, 2/3 of the Eiffel tower) ?

The blades are fiber glass composite now. The tower is almost always steel, though concrete has some inroads. Weight? 1http://www.google.com/url?sa=t&ct=res&cd=8&url=http%3A%2F%2Fwww.mecal.nl%2Ffiles%2Falgemeen%2Fewec2003-ATS_paper.pdf&ei=QgwqSMf-Apys8ASW0PHGCw&usg=AFQjCNGXC0r4dfJh_7uSZ72bJ6y2ShyGYQ&sig2=sUhooGLwJ0sBCJ2WugGG4w" , so let's say 700tons/tower. So 700,000 tons for a 5GW 1000 tower field. The concrete I think is small in comparison.

Do you do with so much less for one windmill than 2 tons of steel and 60 m^3 of concrete (half a m^3 per meter height) ?

It is my opinion - I can be wrong - that the material investment in steel and concrete of one EPR unit is comparable to the amount of steel and concrete needed for these 1000 turbines.

If that's the case, then material cost is going to have a null-effect on comparisons.

Apparently Wind requires a lot of steel; I doubt very much concrete.

 

[vanesch]

Plus rebar steel. Strong reinforced concrete about 5% steel by cross section: 60000m^3*0.05=3500m^3; 3500m^3 * 7900kg/m^3 * 907kg/ton = 26000tons rebar steel.

Hey, that's funny, there's 10 times more steel in the building than in the actual reactor part.
One should make then out of fibre glass...

Is the cooling tower significant? Schmehausen, for example: average diameter ~120M, height 180M, 0.1M thick average(?)= 3.14*120*180*0.1 = 6800 m^3 walls
base = 3.15*60^2* 0.2(?) = 2300m^3, total 9000m^3 for the tower. Say 1000tons rebar steel. Not so much compared to that containment bldg. Call it 70,000M^3 concrete, 29000 tons steel, total project.

Right, which gives us an equivalent budget of 29 tons of steel and 70 m^3 of concrete per turbine, or essentially 70 m^3 of reenforced concrete.

The blades are fiber glass composite now. The tower is almost always steel, though concrete has some inroads. Weight? 1http://www.google.com/url?sa=t&ct=res&cd=8&url=http%3A%2F%2Fwww.mecal.nl%2Ffiles%2Falgemeen%2Fewec2003-ATS_paper.pdf&ei=QgwqSMf-Apys8ASW0PHGCw&usg=AFQjCNGXC0r4dfJh_7uSZ72bJ6y2ShyGYQ&sig2=sUhooGLwJ0sBCJ2WugGG4w" , so let's say 700tons/tower. So 700,000 tons for a 5GW 1000 tower field. The concrete I think is small in comparison.

Apparently Wind requires a lot of steel; I doubt very much concrete.

For these offshore applications, I'm pretty sure that the base on the seafloor requires quite some concrete, but I don't know how it compares to 70 m^3 which would make a base plate of 10 m x 10 m x 70 cm.

 

[baywax]

Here's the basic idea at an NREL test facility.
http://www.nrel.gov/hydrogen/proj_wind_hydrogen_animation.html
Wind runs straight to the grid when needed, when its peaking over load it generates H via electrolysis, is pressurized and stored. Fixed plant storage is not that problematic, unlike vehicle storage. Then when needed the H2 drives either and H2 ICE (in low production now) generators or fuel cells.

Another source of presently wasted H2 is at electrolysis plants around the world. They just burn off the excess H2 instead of storing it. What does it take to collect the H2 rather than burn it off? Probably the same amount of equipment. There must be many other chemical processes going on in industry today that discharge hydrogen rather than store it for re-sale. This represents work that has been done anyway so the efficiency goes up 100%... and you get two or more outcomes for the price of one.

 

[vanesch]

Here's the basic idea at an NREL test facility.
http://www.nrel.gov/hydrogen/proj_wind_hydrogen_animation.html
Wind runs straight to the grid when needed, when its peaking over load it generates H via electrolysis, is pressurized and stored. Fixed plant storage is not that problematic, unlike vehicle storage. Then when needed the H2 drives either and H2 ICE (in low production now) generators or fuel cells.

Sure, all this is nice. This test facility (that's why it is a test facility) is on the 10 KW scale. IN the US we need to go to a 10 million times bigger scale. This is not going to happen in the next few decades, that's the point.
Also, I wonder what the efficiency is of "generated electricity" - "generated hydrogen" - "re-generated electricity". I wonder if you get overall over 30% (especially if the hydrogen is used in a combustion engine), which means that you need 3 times the capacity to account for the variability.

Again, I'm not against this, on the contrary. But these are experiments on a scale where nuclear power was in the 40ies. It took at least 4 decades before this became a major player in the world energy provision.