Rethinking nuclear power.

ABC Unleashed has recently featured an article by environmentalist Geoffrey Russell; Rethinking Nuclear Power.

It’s worth reading.

I like the idea of closing down uranium mines, and using existing stocks of mined uranium efficiently.

Uranium mining is far less environmentally intensive than mining coal, of course, but it’s basically inevitable that all mining is fairly environmentally intensive, and it’s always an appealing prospect if we can mine less material (whilst still maintaining our energy supplies and our standards of living, of course.)

I have to admit, when I first saw Geoff’s claim that we could completely eliminate uranium mining, I was skeptical. So I took a more detailed look.

A nuclear reactor which is efficiently consuming uranium-238 and driving a relatively high efficiency engine (typically, a Brayton-cycle gas turbine) will require approximately one tonne of uranium input for one gigawatt-year of energy output. This high efficiency use of U-238 could be best realized something like an IFR or a liquid-chloride-salt reactor (the latter is essentially the fast-neutron uranium fueled variant of a LFTR). This figure of one tonne of input fertile fuel per gigawatt-year is also comparable for the efficient use of thorium in a LFTR.

There are about one million tonnes of already mined, refined uranium in the world, just sitting around waiting to be put to use, which is termed so-called “depleted uranium”.

According to one source, the exact worldwide inventory of depleted uranium is 1,188,273 tonnes [1].
The total electricity production across the world today is about 19.02 trillion kWh [2].

Therefore, total worldwide stocks of depleted uranium, used efficiently in fast reactors, could provide every bit of worldwide electricity production for about 550 years.

That’s not forever, but it’s a surprisingly long time. And that’s just “depleted uranium” stocks; not including the stocks of HEU and plutonium from the arsenals of the Cold War, and not including the large stockpile of uranium and plutonium that exists in the form of “used” LWR fuel.

I know some thorium proponents aren’t going to like this; but there’s a strong case to be made here that uranium-238 based nuclear energy has a clear advantage over thorium, simply became of these huge stockpiles of already-mined uranium, for which there exists no comparable thorium resource already mined. The 3,200 tonnes of thorium nitrate at NTS is tiny compared to the uranium “waste” stockpile, but they’re both really useful energy resources which can replace the need for more mining.

Any type of breeder or burner reactor utilising ²³⁸U, or ²³²Th, as fuel requires an initial charge of fissile material to “kindle” it; however this requirement for fissile material is quite small; and personally, I think the inventories of HEU and weapons-grade plutonium recovered from the gradual dismantlement of the arsenals of the Cold War are perfectly suited to this purpose – destroying those weapons materials, whilst putting them to a valuable use.

Then again, with the means to completely replace the use of coal and fossil fuels in a way that requires very little or no uranium mining, I really hope the rest of the world keeps buying that iron and copper and bauxite. Alternatively, we’re going to have to start developing a more technologically based economy in this country to make up the reduction in exports of these commodities – perhaps developing and selling reactor technology?

Developing uranium enrichment technology, such as SILEX, is of limited usefulness because the relatively inefficient thermal-neutron fission of ²³⁵U, and hence the need for enrichment, will not supply any large portion of world energy demand in a sustainable fashion over the long term. The small amount of ²³⁵U in nature is of limited significance, over the long term.

Alternatively, perhaps a shake up of agriculture, using extensive desalination to supply fresh water requirements, might be used to replace Australia’s income from coal and uranium. I’m not sure.

Tip ‘o the hat to Barry at Brave New Climate for pointing out this article.

[1]: http://www.wise-uranium.org/eddat.html
[2]: From the World Factbook, 2008 ed. (jokes about the integrity of CIA’s intelligence aside…)

A bit of an apology…

…I’ve been a little busy lately, and you may have noticed the absence of many new posts.

More regrettably, though, is that there seem to be a large number of comments accumulating in the pending-comment-moderation queue, and they haven’t been posted.

So, if you’ve been trying to post comments without success, this is why, and I will make sure they’re all posted now. (Unless there are any I really insist on moderating, but that’s unlikely.) I will have to try experimenting with the WordPress settings regarding spam filtering and automatic comment approval a little bit.

Looking for a particular graphic.

Dear readers;

There’s a certain image that I’ve seen when browsing the web before which I found useful. I’m trying to find this image again, but haven’t seen any success in finding it again.

It’s a pie chart which shows the physical composition of typical used LWR nuclear fuel, showing a breakdown of x % uranium, y % Zircaloy cladding, z % hardware, w % fission products and so forth. This was notable in that it included the portion of the fuel element’s mass which is the cladding and hardware, not just the uranium oxide fuel matrix itself.

Does anybody recognise the graph I’m referring to, and know where to find it online?

Regards.

The argument from appeal to hatred of Howard.

Here’s a comment I received recently, in the context of talking about nuclear power.

“remember John Howard sold his soul to GW Bush, why would yoy [sic] trust anything he supports ?”

We see this occasionally in discussions about nuclear power. It’s the appeal to hatred of Howard, an argumentative technique, similar to a kind of contemporary derivative of the good old fashioned argumentum ad hominem, that goes something like this:

i) John Howard was actively interested in investigating the use of nuclear power in Australia, and was open to the idea.

ii) Of course, everybody obviously knows that Howard is literally pure immoral evil, and he feasts on babies, or something.

iii) Ergo, nuclear power is bad.

You sometimes have the persuasive appeal to hatred of the GOP or hatred of Bush, or something similar, it works in exactly the same way.

Burning money with solar power in Victoria. Again.

It has been announced this week that the Victorian Government will promote renewable energy by spending $100 million to establish a new regional solar power station, subject to the Federal Government matching its commitment.

Premier John Brumby will announce both initiatives today, focusing on the plan for a 330-gigawatt hours per year solar plant with the capacity to power the equivalent of 50,000 homes.

All right. More kumbaya and rainbows and sunshine courtesy of Brumby.

This proposed new solar power station will supposedly generate 330 gigawatt-hours of electrical energy per year. (The Age article originally mentioned a “330 gigawatt” plant, but they later caught the egregious mistake and edited it.)

How much energy is that?

In 2006, Loy Yang unit A in Victoria generated 15,995 GWh of electrical energy, sent to the grid.
(In doing so, it emitted 19,314,994 tonnes of CO₂ equivalent, and a whole lot of other environmentally and aetiologically nasty, dangerous, toxic waste, such as fly ash, SO₂ and NO₂, as well.) That’s just one example of one of the coal-fired generators, of course.

Therefore, this proposed solar power station is generating about 1.88 percent of that one single coal-fired generating station.

How much will this plant cost? We don’t know. The article doesn’t say, nor does Brumby’s original press release. We don’t know how much it costs, and I doubt Brumby knows, either.

…promote renewable energy by spending $100 million to establish a new regional solar power station, subject to the Federal Government matching its commitment.

OK… we know that it costs at least $200 million. There is actually a convenient benchmark which we can use to make an estimate of how much the whole project will actually cost, and that is the $420 million solar energy installation planned by Solar Systems for northwestern Victoria. This is another expensive solar energy project that the Victorian government just loves to talk about as a poster child for their clean, green ways.

The Solar Systems project, with 154 MW of nameplate capacity, will generate 270 GWh per annum, and will cost 420 million dollars. If we assume that the newly proposed 330 GWh/annum installation might cost about the same, for a given amount of capacity, then we can expect that it will cost 513 million dollars.

To replace Loy Yang A, to have the equivalent amount of energy generation, you’d need 49 such installations of this size, at a cost of approximately 25 billion dollars to construct.

If you build a modern* nuclear power plant, with two 1100 MW_e reactors operating with a 90% capacity factor, the plant will generate about 17,356 GWh per annum. That is, such a plant will replace Loy Yang A’s output about 1.09 times over; it’s more than sufficient.

How much does it cost, to build such a nuclear power plant?
Go on, consider an exaggerated, extra-conservative cost estimate from your local greenies. 9 billion dollars? 12 billion? 14 billion? 15 billion?

In every case, even with the most pessimistic cost estimates for nuclear power, it’s far, far cheaper than solar, assuming that you’re actually capable of counting kilowatt-hours.

(* Modern, but not bleeding edge. We’ll consider the presently available modern Generation III LWRs such as Westinghouse AP1000 that are available immediately, not Generation IV fast spectrum reactors, liquid fluoride reactors, or things like that, just to be a little conservative about it.)

Brumby’s press release says that they aim to have the plant operating by 2015. So, they aim to have the plant operating within six years.

Six years? To think that opponents of nuclear energy say that it takes too long to deploy.

If it takes six years to build, and you need 49 of them to replace one coal-fired station, well, would it take 294 years for them to accomplish that goal? Well, perhaps I’m being a tiny bit mendacious. You never know, perhaps they could achieve faster deployment constructing them in parallel, and maybe it would only take 200 years, or 150 years. Maybe.

Six years is in fact sufficient time to construct a nuclear power plant, if you’re serious about doing it and don’t allow it to be delayed. All the nuclear units at the Kashiwazaki-Kariwa nuclear generating station in Japan were each constructed in timescales of between three and five years; Kashiwazaki-Kariwa Unit 2 and Unit 5 both commenced construction in 1985, and both were completed by the end of 1990, within 5 years. Obviously the Japanese operators failed to see any relevance what so ever of a certain ill-fated Soviet graphite pile to their operations.

Even if you want to talk about conservative, drawn out timescales for the construction of new nuclear power in Australia, say, 10 years maybe, it’s still a far, far faster option, for a given amount of energy delivered, than solar or wind.

Nuclear power and terrorist proliferation of nuclear weapons

Is the plutonium that is potentially formed within certain types of fuels in nuclear fission power reactors really suitable for the construction of nuclear weapons? How accessible and usable is such plutonium for such a purpose? How hard would it be to construct a nuclear weapon employing such material? Could terrorists steal nuclear fuel from a nuclear power reactor and construct a working nuclear explosive device, practice?

What characteristics would such a device have? Given the terrible power of nuclear weapons, and the very real threat of terrorists who would love nothing more than to wield such power, these are perhaps important questions to consider.

I assert that, no, there is no real threat here that is anywhere near as plausible in the real world as it is sometimes beaten up to be. Can terrorists steal nuclear fuel, and build a nuclear weapon? No. I don’t think so.

I mainly just wrote this because (i) I just wanted to get this off my chest, and it’s good to have a go at the unrealistic nonsense that gets bandied about without any real factual evidence to back it up, and (ii) because I found the Kessler paper interesting.

This little piece of writing of mine owes a lot to the always entertaining and scientifically interesting posts of NNadir, especially this one, and this one, where I was pointed to the interesting publications of Kessler and colleagues. Love your work, NNadir

My little essay is here (PDF format).

Pointing out of typos, peer review, comments, grammatical suggestions and other interesting discussion and feedback is appreciated.
(I know the sentence is too long in the last paragraph on page 5, and there’s a typo on the first line of page 13. Those are fixed in the CVS. )

I hope you find it enjoyable, interesting and/or useful.

Well, it looks like the Obama administration is going to pull the plug on Yucca Mountain.

Well, there will be no Yucca Mountain facility opening in the US any time soon. But is that a big deal? No. There never was any urgent need for Yucca Mountain. The used nuclear fuel at the civilian power reactors is quite safe where it is, and it isn’t hurting anybody. The current on-site storage can be maintained for many years to come, and it’s just not a problem that requires any pressing intractable attention.

It will be interesting to see what happens in relation to the Nuclear Waste Policy Act – obviously they will have to change the law.
I suppose that money will be put back into the hands of the nuclear utilities, or used by the government to implement recycling of fuel.
I’d be happy to see the money used by the government to implement recycling infrastructure, and/or used by the nuclear generation utilities to implement dry cask storage for all the on-site storage capacity for their fuel that they need and that they’re going to need, until reprocessing and/or central storage is implemented.

It’s worth remembering that we’re not abandoning Yucca Mountain, we’re not “wasting” billions of dollars – the Obama government is not going to backfill it with concrete and burn all the research data. We’re just putting Yucca Mountain on the back burner for a little while, that’s all. If, in 10 years, we decide that Yucca Mountain wasn’t such a bad idea after all, we can always go straight back to it where we left off.

I think that’s not actually all that bad, because it gives us time to step back, breathe, and realise that taking this used LWR fuel, which is 96% unchanged uranium, declaring it to be so-called “waste”, and throwing it in Yucca Mountain really is a little stupid.

Off the top of my head I can’t remember how deep the Yucca tunnels are, but perhaps the facility will be useful for particle physics experiments (neutrino physics, dark matter detection and the like) just like the WIPP site in New Mexico.

As much as I fully support sensible recycling of nuclear fuel, and I hate to see good useful material “wasted”, I think, yes, it’s worth ultimately having a geological repository, although it’s certainly not needed urgently.

Even with the efficient use of uranium and actinides, and the extraction of useful fission products, I think we’re going to be producing medium-lifetime radioactive fission products (such as Cs-137, Tc-99, Sr-90, or what-have-you) at a rate which will exceed their consumption for useful applications, and therefore, we will have surplus material that will probably be best going to deep geological storage. Add in the transuranic-contaminated waste from the Cold War and the weapons facilities, and industrial and scientific radioactive waste, and yes, it really doesn’t hurt to have a deep geological repository such as Yucca mountain.

A roundup of some interesting things.

A few interesting things I’ve come across this week:

i) In pure water, (and in particular in ice, which has a much greater density of hydrogen bonds) electric charge is primarily carried not by electrons, but by a flow of mobile protons. (Or deuterons, in D₂O.)

Further reading here and here.

ii) A compendium of water-related pseudoscience and quackery. From magical quantum water purification, to “water memory”, to converting your car to run on water, it’s all discussed here.

iii) Neodymium-iron-boron magnets are dangerous!

Super-strong neodymium-iron-boron permanent magnets are very cool. They’re fun to play with, and they’re also extremely useful for many technological applications.

But they should be treated with a great deal of respect, and not toyed around with, especially not if they’re large – anything bigger than a few cubic centimetres.
A pair of these magnets the size of cigarette packets are not novelties and they’re not toys – they will take off your hand quite easily if they’re not treated with respect.

Do not want!

Finally:
To Mars by A-bomb: The Secret History of Project Orion.
I think I’ve posted little bits from this before, but I was delighted to find that someone’s posted the entire one-hour series on YouTube. Very, very cool.

Here’s the first part, the next five parts are at the above page.

Watching the start of this program, I was actually a little surprised to see that there actually exists video footage (indeed, colour video footage) of the assembly of the Gadget for the Trinity test in 1945.

‘Dirty bomb’ parts found in slain man’s home?

The Bangor Daily News reports that one James G. Cummings, who police say was shot to death by his wife two months ago, “allegedly had a cache of radioactive materials in his home suitable for building a “dirty bomb.””

According to an FBI field intelligence report from the Washington Regional Threat and Analysis Center posted online by WikiLeaks, an organization that posts leaked documents, an investigation into the case revealed that radioactive materials were removed from Cummings’ home after his shooting death on Dec. 9.

The report posted on the WikiLeaks Web site states that “On 9 December 2008, radiological dispersal device components and literature, and radioactive materials, were discovered at the Maine residence of an identified deceased [person] James Cummings.”

It says that four 1-gallon containers of 35 percent hydrogen peroxide, uranium, thorium, lithium metal, thermite, aluminum powder, beryllium, boron, black iron oxide and magnesium ribbon were found in the home.

Also found was literature on how to build “dirty bombs” and information about cesium-137, strontium-90 and cobalt-60, radioactive materials. The FBI report also stated there was evidence linking James Cummings to white supremacist groups. This would seem to confirm observations by local tradesmen who worked at the Cummings home that he was an ardent admirer of Adolf Hitler and had a collection of Nazi memorabilia around the house, including a prominently displayed flag with swastika. Cummings claimed to have pieces of Hitler’s personal silverware and place settings, painter Mike Robbins said a few days after the shooting.

Now, of course, this seems like a bit of a beat-up – but I’m not sure who’s to blame here, the newspaper, or the perhaps overly dramatic (internal) FBI report.

The memo leaked on WikiLeaks reports that:

“State authorities detected radiation emissions in four small jars in the residence labelled ‘uranium metal’, as well as one jar labelled ‘thorium’. The four jars of uranium carried the label of an identified US company.”

“Further preliminary analysis on 30 december 2008 indicated an unlabeled jar to be a second jar of thorium. Each bottle of uranium contained depleted uranium-238. Analysis also indicated the two jars of thorium held thorium-232.”

Now, regarding this US company. I have a pretty good suspicion who this company is – there aren’t too many companies that sell small samples of depleted uranium to the public – but I’m not going to mention the company by name, simply because they do not deserve to be unfairly tarnished or persecuted in relation to this incident.

This company provides quite a few products which are very interesting and very useful in scientific teaching, education and research, including some items which are extremely difficult to find on the market anywhere else, and they already cop enough persecution and flak as it is. Nothing they sell poses any special danger to the community at large, and small samples of uranium metal are, personally, one of the least dangerous things they sell.

The company in question, from what I recall, sells (depleted) uranium metal samples in 5 gram bottles, and used to sell thorium as one-gram samples.

If these samples were what these bottles possessed by this person were, then you’re talking about approximately 20 g of depleted uranium metal, and approximately 2 g of thorium metal. That’s about 10 microcuries of uranium, and about 0.22 microcuries of thorium.

There’s nothing that constitutes any radiological hazard to anybody. A bucket full of uranium-bearing rock picked up out of the ground would contain more radioactivity than this. Uranium-238 and thorium-232 are some of the least radioactive substances you can find that can still actually be called radioactive. They’re completely, utterly irrelevant to any threat of a radiological weapon, at all.

That said, however, I’m sure it is within the limits plausibility that this person was intent on trying to build a radiological weapon, he simply didn’t go about it in a particularly effective fashion.

Hacking up some Arduino-derivative hardware.

I was having a chat with some people the other week at linux.conf.au – I’m sorry, but I’m terrible at learning and remembering new names and faces, and I can’t remember who – about the idea of a future LCA workshop on the subject of the Arduino platform, where delegates are actually given their own kit that they can solder together – getting a little more hands-on with the hardware than using (the admittedly good) pre-assembled Arduino reference-design dev boards.

I mentioned the notion of having such a kit based exclusively on through-hole components, so that it’s easy to assemble by people with minimal experience with SMD soldering. However, the FTDI USB UART devices aren’t available as through-hole devices, only as SMD, so you’re going to need at least one SMD component. That is, unless you want to use RS232 as the interface to the PC, not USB. However, compared to RS232, USB is kick ass.

So, I thought, why not use a Arduino-style dev board that includes both RS232 and USB as well – so, you can have a fully functional board with USB interface if you’re brave enough to solder the SMD – but if you don’t, that’s OK, but you will need to use RS-232 as well as an external power supply.

That’s a pretty good idea, I thought. The people I mentioned it to agreed.
But no such hardware platform is available off the shelf anywhere.

So I created it.

This has been occupying my free time in between free moments for a significant part of the week at LCA
Doesn’t a conference such as LCA just totally put you in a hacking groove? It does for me. Of course, I’m a hardware, more so than software, hacker.

Please feel free to download and check out the schematic file and the PCB layout files.

Hardware IP released under the TAPR Open Hardware License (http://www.tapr.org/OHL).

These are CADsoft EAGLE files; they’re also sufficiently small such that the freeware licensed version of EAGLE is perfectly fine to work with them. Yeah, I know, I know, it’s proprietary software. I’ll have to learn gEDA and re-do the designs for extra FOSS satisfaction.

So, what hardware do we have?

The hardware is extremely close to the Arduino Duemilanove reference board schematic design, which it is based on. I’ve just added the MAX232A and D9 port for RS232, really. The UART connections are bought out to a 2×3-pin header block, so that jumpers can be used to patch the ATMega into either the FT232RL USB UART chip or the MAX232A level translator for RS232.

In theory, if you wanted to, for some strange reason, and you’ve populated both sets of interface components, you could have Tx routed to the USB UART, and Rx routed to the RS232 interface, or vice versa, if you wanted to. Also, you can, in theory, put the jumpers in to connect the hardware UART in the AVR to the USB port, and then code up a secondary UART in software using other DIO pins on the microcontroller, and then patch those DIO pins onto the UART select jumper block so that they’re connected to the MAX232, then you can plug the Arduino into the PC via USB, and then plug some completely separate RS232 peripheral into the microcontroller, too!
(Anyone for an OpenWRT router under microcontroller control?)

Additionally, all components are through-hole, except the FT232RL chip. Because through-hole components are used throughout, it’s a bit bigger than ordinary Arduino boards, and is physically not compatible in terms of form factor; that is, it is not (as the PCB currently stands) presently compatible with Arduino-compatible “shield” plug-in daughterboards. Perhaps somebody with elite PCB-routing skills could overcome that with a revised board layout?

The PCB as it currently stands maybe isn’t perfect. Perhaps it could be better. Perhaps you could make it better.
I’ve routed tracks on both layers so that there are no vias, instead, component leads are used as vias by soldering them to both layers – this can be difficult for certain types of components, and can affect the best component choices – eg. machined-pin IC sockets are easier to use. I find this method faster and easier when using home-fabbed PCBs, but if you can get professional PCBs fabbed inexpensively in China, then it might not be as important because you can get plated through-holes done at fab time for cheaper than you might think.

Unfortunately, I had to cave in in the end and include two conventional vias, near the FT232 chip, in order to route everything. Putting in manual vias with a bit of wire isn’t a big deal for just a couple of vias, anyway.

Some notes:
* You must use a MAX232A, not a MAX232, since the charge-pump capacitors are only 100 nF.
* Power input autodetection is implemented exactly as it is on the Arduino Duemilanove reference design.
* Most components are standard off-the-shelf things available from the workbench of the well-stocked hardware geek or the local Jaycar, with very few exceptions.
* Those exceptions include the ATMega168 itself, the FT232RL, the voltage regulator IC (If your input voltage is high enough I suppose you could use ye olde 7805 instead of the more exotic LDO regulator, but remember that it has a different pinout.) The FT232RL is available from DonTronics, in Australia.
* I wasn’t sure which P-channel MOSFET to use to switch the USB power rail – it probably doesn’t need to be a big honking TO-220 device, but I couldn’t find a more compact TO-92 device that I could confirm easy availability for (that is, from Jaycar or Altronics or whatever, in Australia). Finding a TO-92 packaged device that takes less board real estate would be nice.
* If you’re using the board as it stands now with the TO220 FET, don’t get the FET and the regulator swapped around! Also, all the capacitors are just identical 100 nF, with the exceptions of the two 22 pF crystal load capacitors and the two large electrolytics in the power supply.
* Also, there is the little fuse included in series with the USB power rail. The Duemilanove reference board includes some sort of little resettable polyswitch-style circuit breaker. I’m not sure where you could source one.

In any case, I hope you like it, I hope you find it useful, and I’d love you hear your comments.