Physical Insights

An independent scientist’s observations on society, technology, energy, science and the environment. “Modern science has been a voyage into the unknown, with a lesson in humility waiting at every stop. Many passengers would rather have stayed home.” – Carl Sagan

Archive for the ‘life-cycle analysis’ Category

” Nuclear’s CO2 cost ‘will climb'”.

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The BBC is reporting that:

The case for nuclear power as a low carbon energy source to replace fossil fuels has been challenged in a new report by Australian academics.

It suggests greenhouse emissions from the mining of uranium – on which nuclear power relies – are on the rise.

Availability of high-grade uranium ore is set to decline with time, it says, making the fuel less environmentally friendly and more costly to extract.

A significant proportion of greenhouse emissions from nuclear power stem from the fuel supply stage, which includes uranium mining, milling, enrichment and fuel manufacturing.

Others sources of carbon include construction of the plant – including the manufacturing of steel and concrete materials – and decomissioning.

You can read the rest of the original BBC article here.

Perhaps more significantly, you can download the original academic paper in question here.

I will quote a couple of paragraphs worth:

Overall, the data clearly show the sensitivity of sustainability assessments to the ore grade of
the uranium deposit being mined and that significant gaps remain in complete sustainability reporting and accounting. This paper is a case study of the energy, water, and carbon costs of uranium mining and milling within the context of the nuclear energy chain.

In summary, the extent of economically recoverable uranium, although somewhat uncertain, is clearly linked to exploration effort, technology, and economics but is inextricably linked to environmental costs such as energy, water, and chemicals consumption, greenhouse gas emissions, and broader social issues. These crucial environmental aspects of resource extraction are only just beginning to be understood in the context of more complete life cycle analyses of the nuclear chain and other energy options. There still remains incomplete reporting however, especially in terms of data consistency among mines and site-specific data for numerous individual mines and mills, as well as the underlying factors controlling differences and variability. It is clear that there is a strong sensitivity of energy and water consumption and greenhouse gas emissions to ore grade, and that ore grades are likely to continue to decline gradually in the medium- to long-term. These issues are critical to understand in the current debate over nuclear power, greenhouse gas emissions, and climate change, especially with respect to ascribing sustainability to such activities as uranium mining and milling.

So, to summarise exactly what the paper says:

There are some inputs of energy  associated with the nuclear fuel cycle on a whole-of-life-cycle during uranium mining and milling, and in practice at present there are some carbon dioxide emissions associated with these energy inputs.

As reserves of easily recoverable high-grade uranium ore decline, assuming that the greenhouse-gas intensity of the energy inputs into the mining operations remain comparable, the whole-of-life-cycle greenhouse gas emissions intensity of nuclear energy might be expected to increase somewhat.

I think we already know that. Everyone already knows that.

The lead author of the paper, Gavin Mudd, is an Australian academic with a background in geohydrological engineering. He is a nuclear energy skeptic – well, not so much a nuclear energy skeptic as someone who is skeptical of the ecological sustainability of current uranium mining practices. His main area of expertise and interest with regard to nuclear energy is uranium mining.

I use the term “nuclear energy skeptic” because it’s reasonably clear that he’s anti-nuclear-energy – but I think it’s almost uncharitable and unfair to put an academic who puts forward their arguments in terms of reasonably well constructed academic papers in peer-reviewed science journals in the same category as the likes of Wasserman, Gunter or Caldicott.

This paper does not at all say “nuclear energy is unsustainable” or “uranium mining is unsustainable” – once the journalists apply a little spin to it, however, it’s easy to see how many could try and apply this paper, and especially press articles like the above, towards evidencing such a conclusion.

Describing the fact that there are energy inputs associated with uranium – which we already know – doesn’t answer the real question at all – How does the whole-of-life-cycle greenhouse gas intensity per MWh of electricity generation actually quantitatively compare to the whole-of-life-cycle greenhouse gas intensity of other energy generation technologies?

Sure – it’s somewhat reasonable to suggest that these quantities will change over the long term, into the future. Quantitatively, how will they be expected to change?

I should add, finally, that this paper is notable for being – perhaps – the first ever nuclear-skeptical study of the energy and greenhouse gas intensity of the nuclear fuel cycle that does not invoke the work of van Leeuwen and Smith. In fact, in terms of the quality of the source material cited, this paper seems pretty good.

Expansion at Olympic Dam means increased energy inputs (of course).

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Apparently, some people out there are shocked with new projections that expanded operations, proposed to be completed around 2013, at BHP Billiton’s Olympic Dam facility will entail significant expansion of the mine’s electricity consumption – projected to be an average of 690 megawatts per year, or around 40% of South Australia’s total electricity consumption, when the expansion is complete.

Here’s the complete story, from

(As an aside, I’m quite pleased to note, when reading the comments on the above-linked webpage, just how much pro-nuclear-energy sentiment seems to be out there.)

Olympic Dam is a copper mine. When the expanded production reaches full capacity in 2015 or so, 450,000 tons of copper metal will be produced annually.

There is a little bit of uranium, gold, and a couple of other things mixed into the orebody which are valuable too, so they extract them as well when the copper ore is processed.

It’s a homogeneous orebody – the uranium and copper and things are all mixed together, so it is impossible to mine the copper without mining uranium, too.

For that 450,000 tons of copper metal that will be produced, only about 14,000 tons of uranium oxide will be produced. The uranium is only a byproduct.

Remember – without copper being mined out of the ground, no electricity of any kind, clean, green or not, can be generated, distributed or used. Without production of aluminium metal, a popular target of so-called environmentalists, electricity transmission over overhead cables cannot be done.

Even since the stone age or the bronze age, mining has been integral to the existence of our technological civilisation. Even as we move to clean sources of energy to power our technological civilisation, such as geothermal and nuclear energy, mining will always be essential.

Now, the expanded mine will consume 690 megawatts of electrical power, on average.

A typical nuclear power reactor generating 1 gigawatt of electricity requires an amount of uranium fuel corresponding to about 200 tons of natural uranium in the form of uranium oxide per year.

So, Olympic Dam will consume 690 megawatts of electricity – and it will produce enough uranium in one year to generate 70 gigawatts of electricity for one year –
over one hundred times the total power consumption of the mine.

Yes, you might be thinking that this ignores the other energy inputs into the nuclear fuel cycle – but it also assumes an extremely inefficient once-through fuel cycle using low-enriched uranium in current light water reactors, without recycling of fuel.

Of course, one must remember that the vast majority of the energy input at Olympic Dam goes into the extraction and smelting of copper metal – the overall “energy gain” typically associated with actual uranium mining operations are typically much higher than 100.

Another point that anti-mining and anti-nuclear-power activists love to make in Australia is that mines such as Olympic Dam use too much water.

The Olympic Dam mine consumes about 30 megalitres of water a day – 30 million litres, in total, for the township, as well as all mining operations. Is that a lot?

Olympic Dam, at present, produces about 200,000 tons of copper annually, along with a relatively small amount of uranium, about 4300 tons of U3O8.

Now, I’m not an expert on mineral extraction, hydrometallurgy, and mining operations, but I will make the rough assumption that the production of one ton of copper metal consumes the same amount of water as the production of one ton of uranium oxide. Therefore, we infer that uranium production at Olympic Dam consumes 2% of the total amount of water, or 600,000 litres per day, or 140 litres of water per metric ton of uranium oxide produced.

If 200 tons of natural uranium in the form of uranium oxide is sufficient to make up the fuel for a 1 GW nuclear power reactor for one year, and that reactor operates with an 90% capacity factor, then the production of Uranium at Olympic Dam then consumes 3550 litres of water per TWh of electricity that can be produced from that uranium.

For comparison, the mining of coal consumes about 200 litres of fresh water per ton of coal produced. Given that a typical coal-fired power station consumes about 0.5 metric tons of coal to produce 1 MWh of electricity, the mining of coal for electricity generation consumes 100 million litres of water per TWh of electricity production.

Indian Point Nuclear Dead Baby World Tour!

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Isn’t this the most tasteless propaganda you’ve seen all year?

Indian Point Nuclear Dead Baby* World Tour. It’s affiliated with the creator of a certain other crazy lepidopterological anti-Indian Point blog. You all know the one.

* Disclaimer: The site does not actually include any references to any actual real children hurt or harmed by nuclear energy.

Now, let’s see.

“To bring attention to this issue, to oppose Entergy’s attempts to relicense these dangerous reactors, this blog will be sending symbolic dead babies (dolls) out on a world tour by leaving them at various locations.”

So, unfortunately, you couldn’t find any actual babies hurt or killed or harmed by nuclear energy, for real, in the real world?

Apparently, whilst there’s no evidence of any kind that nuclear energy actually does hurt or harm or kill real babies in the real world, it however does symbolically kill babies.

My god, won’t anybody think of the symbolic children?

“First, it seems only fair that Andrea speak, since this Indian Point Dead Baby Tour is about them, the dolls, and who it is they represent in this battle.”

Oh, silly me. It’s about dolls? Indian Point kills dolls? Not actual real, living, human babies? It seems I was misled to believe that there are somehow actual living children being killed by Indian Point… I must have been mistaken.

I hate to break it to you like this, but they’re dolls. They’re not alive – if Indian Point is killing dolls, it must be pretty dangerous indeed… right?

First, some important news on our forward progress on this environmental direct action campaign:

3. Buried three dolls in the mulch in my backyard gardens in the hopes of giving them a bit of a different soiled look, and took some incredible photographs that I hope to load onto my hard drive, again on Sunday.

That’s your environmental direct action campaign? I’m trying not to laugh.

“The doll is so elegant, that it is going to be the doll shipped over to Elena in the Ukraine with the hope that she will agree to take it with her on her next motorcycle trip through Chernobyl’s fallout zone.”

On her website, Elena Filatova posted photographs of her alleged motorcycle trips in the area around the Chernobyl nuclear power plant, 18 years after the power reactor disaster there. She mainly visited the virtually abandoned city of Pripyat, Ukraine.

Filatova took a large number of photographs of buildings, cottages, rusting carnival equipment, the interiors of schools and homes, and even a couple people who had since returned to the area. The photos are arranged in the form of a story presented as an account of a trip by a biker who got a permit to travel alone in the radiation zone. However, Chernobyl tour guides and tourists to Chernobyl have claimed that Filatova visited the Chernobyl Exclusion Zone only as part of an organized tour. Chernobyl tour guide Yuriy Tatarchuk recalls that Filatova “booked a tour, wore a leather biker jacket and posed for pictures.” Her website appeared soon after.

“There is no bigger myth within the nuclear energy than their claim that nuclear energy and commercial reactors are and environmentally friendly CO2 source of electricity. From the very beginning of the uranium fuel cycle, the massive creation of and dumping of CO2 into our environment begins, as well as a trail of far deadly contaminants. First, you have to get the uranium out of the ground…uranium mining is very equipment intensive, and the large pieces of equipment use MASSIVE amounts of fossil fuels. Further, it takes tons and tons of of ore containing trace amounts of uranium to get enough actual raw uranium to be of any use. This means said materials have to be carted to processing plants…again, said transportion of such vast quantities of these raw start up materials burn up vast amounts of carbon based fuels, adding to nuclear CO2 contributions to Global Warming.”

Yes, the mining of uranium, the enrichment of uranium, the construction of reactor infrastructure and so forth consumes energy, in just the same way as mining and refining bauxite into aluminium to construct massive wind turbines, along with the construction of the infrastructure itself, consumes large amounts of energy, often generated via relatively polluting energy sources, such as burning fossil fuels.

The independently produced, accredited, Environmental Product Declarations for Swedish energy utility Vattenfall’s Forsmark Nuclear Power Plant find that, averaged over the entire lifecycle of their nuclear power plant including uranium mining, milling, enrichment, plant construction, operating, decommissioning and waste disposal, the total amount of CO2 emitted is 3.3g per kWhe .

The proposed Woodlawn wind farm pro ject in New South Wales has also made available a detailed Environmental Impact Statement, in which greenhouse gas emissions are quantified on a whole-of-life-cycle basis.

Excluding values for wind farms that are significantly different from the proposed Woodlawn Wind Farm, GHG emissions on a life cycle basis range from 7-20 kg CO2e /MWh. This represents the GHG emissions from all activities, including the construction, transportation, assembly and operation of the turbines.

The idea that whole-of-life-cycle analysis can demonstrate that nuclear energy is unsustainable, both on an energy intensity basis and a greenhouse gas intensity basis, is based on a very limited set of highly dubious science, which has been widely rebutted, and found to be irreconcilable with the body of scientific literature established relating to the energy and greenhouse gas intensities of the nuclear fuel cycle.

I could go on, but this same bullshit argument has been done over, and over, and over, and over so many times… I’m sick of repeating myself.

“What lunacy sees the world wanting to build 2200 new nuclear reactors when the first 437 aging reactors have been such a dismal failure, and killed so many innocent people?”

Nuclear energy is the largest source of greenhouse gas free electricity in the world, and it is also the safest – one of the safest industrial enterprises in existence. Aside from Chernobyl, commercial nuclear power, operated safely in the Western world, has harmed or killed almost nobody – megawatt-hour for megawatt-hour, wind turbines, for example, are far more dangerous. I’d call that quite a success story, and I challenge anybody to provide credible evidence to the contrary, if they disagree.

“Look just under the surface of the commercial nuclear industry, and you find a trail of death…it is no coincedence that every county within 100 miles of a nuclear facility has elevated cancer rates when compared with counties outside of that 100 mile circle. Look at both wars in the Middle East (Desert Storm, and the Iraq War), and you find our soldiers coming home with strange illnesses, illnesses caused by their overexposure to depleted uranium. Already in Iraq, mothers are giving birth to children with horrible deformities, deformities caused by that same exposure to Depleted Uranium, and where does that Depleted Uranium come from? The production cycle employed to produce fuel for commercial nuclear reactors.”

Is there any credible physical evidence, any evidence of any kind, that “every county within 100 miles of a nuclear facility has elevated cancer rates when compared with counties outside of that 100 mile circle”?

What does the use of uranium munitions have to do with nuclear power? Nothing!

“That’s one of the big problems with the nuclear cycle…there is no such thing as the peaceful atom, no matter how you try to dress it up. Additionally, anywhere nuclear goes in all of its various forms, death is soon to follow. From its earliest days, even pre-dating the Manhattan Project, the exploration and exploitation of uranium has brought with it horrid deaths, devastating cancers, birth defects and destruction on a level almost unimaginable.”

Is there any evidence of any kind to support such claims in the real world?


“Going further, George Bush, our government, our military machine opposes Iran gaining the capability of enriching uranium for a very simple reason…with the capability of enriching said uranium for nuclear reactors, you gain as a part of the waste stream from enrichment operations the byproduct of Depleted Uranium.”

“You see, our Pentagon needs the commercial nuclear industry, and the infrastructure it takes to power it for its own evil purposes, including vast stockpiles of Depleted Uranium, which is used in numerous weaponry to make armour piercing ammunitions and war heads.”

Riiight. The uranium used in anti-tank kinetic penetrator munitions really doesn’t care what isotopic composition it is… Natural uranium, with no enrichment or depletion of particular nuclides, is perfectly usable for this purpose. Depleted uranium is not specifically required for this application at all.

“As our campaign moves along, we’ll share many of these photographs with our readers, but tonight, thought I would share a peek into the dolls long involvement in the Nuclear Industry, by introducing you to Priscilla and some of the members of her family who were forced, like many of our soldiers to endure nuclear bomb testing under the guise of the Friendly Atom and CHEAP ELECTRICITY.”

Exactly what, at all, does nuclear weapons testing have to do with generating electricity? Absolutely nothing.


“The tragic events surrounding the horrific aftermath of Japan’s 6.8 on the richter scale earthquake show us just how fragile and vulnerable nuclear reactors really are.”

The effects of last year’s earthquake on the Kashiwazaki-Kariwa nuclear power plant in Japan actually demonstrate just how robust nuclear power plants are, when subjected to the terrible destructive power of an earthquake, something that is capable of razing entire cities.

Next up, we’ve got a picture of a Hiroshima bombing victim with terrible thermal burns.

This has got nothing, absolutely nothing at all, to do with Indian Point, Entergy, or nuclear energy at all.

In war, especially the most terrible of wars, as the second world war was, many civilians suffer terribly as a result of war – and civilians and soldiers alike suffer terrible thermal burns, as well as all sorts of other injuries even before the advent of nuclear weapons, and after the advent of nuclear weapons, with nuclear weapons, or without nuclear weapons.

I’d like to see a world without wars at all.

“incredibly heart wrenching photographs of the fallout area in and around Chernobyl”


This has got nothing, absolutely nothing at all, to do with Indian Point, Entergy, or nuclear energy at all, aside from the large-scale production of weapons-grade plutonium in the Soviet Union at the height of the Cold War, with electricity being produced by the nuclear reactors as well, using extremely dangerous, unstable nuclear reactor technology, with no type of containment vessel around the nuclear reactor at all, that would never have been approved or licenced in the United States or anywhere else outside the Soviet Union, at any point in history.

Climate of Hope – an anti-nuclear look at nuclear energy, energy systems and climate change.

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(168Mb video download, running time approximately 30 minutes)

This is a documentary video produced by the Anti-Nuclear Alliance of Western Australia – whilst they clearly make some statements that I contend, for the most part, the video is well produced, and the graphics and so forth are very well made.

This video starts off looking promising serves as a good factual primer on the science of the nuclear fuel cycle, energy generation, and the issue of fossil fuels and artificial forcing of the greenhouse effect. One starts to think, upon watching the first 5-10 minutes, that this is a good unbiased piece, with the film focussed on statistics and factual scientific and historical discussion, with none of the emotionally manipulative rubbish that anti-nuclear-power groups often produce.

It’s worth watching, anyway.

Now, a rebuttal of the parts I think deserve a rebuttal. Suffice to say, there’s a lot, and once I get ranting, it can be difficult to stop.

I’m sure you’ve all heard all this before – this is preaching to the converted. But I needed to get it off my chest – again.

200 tons of U3O8 is about the appropriate amount of Uranium required to fuel a nuclear power reactor for one GW-year. Assuming 0.15% U3O8 in the ore, then 133,200 tons of ore must be processed to support one GW-year of reactor operation, so, these numbers are OK.

It is claimed that the Olympic Dam mine in South Australia consumes 33 megalitres of water a day. I don’t have a reference for this data in front of me, so I’ll take their word for it.

However, since we’re talking about the nuclear fuel cycle, it must be remembered that Olympic Dam is predominantly a copper mining operation, producing about 220,000 tons of copper annually, along with a relatively minor amount of uranium, about 4500 tons of U3O8.

The other elements present in the orebody at Olympic Dam – uranium, silver and gold – are combined together in the orebody, with the uranium extracted during the processing of copper ore – essentially, a byproduct of copper production. Silver and gold, along with selenium and tellurium in small quantities, are extracted from the “anode slime” produced in the electrolytic refining of copper. Thus, even if the Uranium was not being extracted and marketed, the same amount of ore is still being mined out of the ground.

Now, I’m not an expert on mineral extraction and mining operations, but I will make the rough assumption that the production of one ton of copper metal consumes the same amount of water as the production of one ton of Uranium oxide. Therefore, we infer that Uranium production at Olympic Dam consumes 2% of the total amount of water, or 660,000 litres per day, or 53.5 kilolitres of water per metric ton of uranium oxide produced.

If 200 tons of Uranium Oxide is fuel for a 1 GW nuclear power reactor for one year, and that reactor operates with an 80% capacity factor, then the mining and milling of Uranium at Olympic Dam, then, consumes 1.53 megalitres of water per TWh of electricity produced from that uranium.

For comparison, the mining of coal consumes about 200 litres of fresh water per ton of coal produced. Given that a typical coal-fired power station consumes about 0.5 metric tons of coal to produce 1 MWh of electricity, the mining of coal for electricity generation consumes 100 megalitres of water per TWh of electricity production.

Considering ore with a uranium oxide concentration of 0.15%, as above, 133,200 tons of ore needs to be mined to operate a typical, current technology, 1 GW LWR for one year. A 1 GW reactor operating for one year with a capacity factor of 80% produces 7 TWh of electrical energy – hence, 19 tons of ore mined per GWh. For comparison, again, 500 metric tons of coal needs to be mined and burned to generate the same amount of electricity.

Given that once used nuclear fuel is removed from a typical current reactor, a full 96% of the fuel material, by mass, is Uranium, completely unchanged from when it went into the reactor, and a further 1% of the fuel is good nuclear fuel in the form of plutonium, strictly speaking, if this uranium is recycled and used efficiently, then only 3% of current uranium fuel consumption is needed – 570 metric tons of uranium ore mined per TWh, as contrasted with 500,000 metric tons of coal per TWh.

The “tailings” from Uranium mining contain the radioactive daughter products of Uranium-238 – Thorium-234, Protactinium-234, Uranium-234, Thorium-230, Radium-226, Radon-222, Polonium-218, Astatine-218, Radon-218, Lead-214, Bismuth-214, Polonium-214, Thallium-210, Lead-210, Bismuth-210, Polonium-210 and Thallium-206.

Of these 17 radionuclides, only five have significantly long half-lives – U-234, Th-230, Ra-226, Pb-210 and Po-210. The remainder have half-lives of between 24 days for Th-234, down to 1.5 seconds for At-218, and 164 microseconds, for Po-214.

Must the tailings from Uranium mining be isolated from the environment for “tens of thousands of years”? Well, the half-life of U-234 is 245,500 years, and the half-life of Th-230 is 75,380 years. However, these half-lives are dwarfed by the half-life of Uranium-238 itself, with a half-life of 4.47 billion years, created in supernovae, billions of years ago.

There is no nuclear transformation of these tailings during uranium extraction – all these daughter products are produced in exactly the same quantities that they were all originally present in, in the original uranium bearing rock.

As such, these radioactive minerals can simply be put back in the original mine, and sealed up with the rock that was originally extracted in the mining operation. Since this is where all these radioactive minerals came from in the first place, the same nuclides, in the same quantities, it is hard to believe that such practice is somehow unsafe or ineffective.

Now, we have the claim that uranium enrichment is a key technology for nuclear proliferation. Uranium must be enriched up to a very high concentration of U-235 for use in a nuclear weapon, and uranium enrichment plants, especially those capable of producing weapons grade material, are very large scale industrial facilities, taking up great volumes of space and consuming a significant amount of energy themselves – they are not easy to hide. The great difficulty involved in the enrichment of uranium, especially to very high levels, is the main reason why plutonium is greatly preferred as the basis for nuclear explosives. Uranium enrichment plants employed in the civilian nuclear fuel cycle can be subject to inspection by the International Atomic Energy Agency, where the nations using them are signatories to the NPT, and international schemes such as the Global Nuclear Energy Partnership can allow nations access to nuclear fuel technology whilst controlling the widespread employment of potentially proliferation-sensitive technologies.

Now, we have the big scary looking list of radionuclides, and accompanying half-lives.

Let’s see – Selenium-79, Zirconium-93, Strontium-90 and so forth. OK, these are reasonably long lived fission products – they comprise the 3% by mass of the used fuel that is not usable as recycled fuel. Some of these materials are valuable, and have potentially important and economical industrial applications, however, it is unlikely that world production of such materials in nuclear reactors will all be consumed, meaning that a significant portion constitutes radioactive waste which needs to be disposed of – most likely, in a deep geological repository.

Rubidium-87 has an extremely long half-life – 49 billion years – meaning that, like Uranium-238 and U-235, it is abundant on Earth, as a cosmogenic nuclide created in supernovae, and comprising 28% of all Rubidium occurring in nature. Similarly, Potassium-40 is a naturally abundant, cosmogenic, primordial radionuclide, which is not created artificially in reactors.

Krypton-83, with a half-life of 10 years… and Calcium-42, claimed to have a half-life of 14,000 years… now just wait one minute. These nuclides are stable – non-radioactive. Whilst I can see how it might be possible to get Kr-83 confused with Kr-85 – a fission product with a half-life of 10.78 years – there are no radioactive nuclides of calcium with a half-life of anything close to that figure. Anyway, Ca-42 is not a fission product. Yttrium-90 is the decay product of Sr-90, with a half-life of only 64 hours.
We see Cobalt-60, Iron-55 and Nickel-63 and Nickel-59 – whilst these themselves are not fission products, they are produced as neutron activation products in the steel and metal structures of the intra-reactor assemblies and reactor vessel – only becoming significant in the form of the intermediate-level waste stream produced during decommissioning of the power reactor. Whilst small amounts of Carbon-14 and Tritium are produced in the cooling water and similar during reactor operation, Beryllium-10 is quite uncommon.

Whilst it is claimed that used nuclear fuel needs to be isolated from people and the environment for hundreds of thousands of years, the radioactive fission products that make up the waste component of the used nuclear fuel – only 3% by mass, remember – will remain significantly radioactive for only 300-500 years.

The film claims that in time, the waste “will escape” even the best engineered containment, and that it is not clear if deep geological disposal of radioactive waste will be possible in practice – however, the process of radioactive decay is absolutely immutable, and the waste only needs to be isolated from the environment for perhaps 500 years, until it is no more radioactive from the uranium ore whence it came – assuming the actinides present are consumed via sensible recycling of the fuel.

Observation of the two-billion year old natural nuclear fission reactors at Oklo provides conclusive empirical evidence that a geological repository is capable of isolating these radioactive waste products from the environment over timescales up to billions of years – amply sufficient for even the longest lived nuclides to completely decay. When the operation of the sixteen nuclear reactors at Oklo was over, nature showed that it could effectively contain the radioactive wastes created by the reactions. It is clear, from this observation of the physical characteristics of nature, that it is possible to isolate such radioactive materials from the environment over the time scale required.

Sweden’s SKB – amongst other such efforts around the world -is engineering a permanent, deep underground, repository for radioactive waste, that requires no monitoring by future generations.The spent nuclear fuel will not be reprocessed, but the used fuel assemblies will be encapsulated in copper. The copper canisters will then be deposited in the bedrock, embedded in bentonite clay, at a depth of 500 metres.


The KBS-3 method used by SKB calls for the spent nuclear fuel to be encapsulated in copper. The copper canisters will then be deposited in the bedrock, embedded in clay, at a depth of about 500 metres. When deposition is finished the tunnels and rock caverns will be sealed.

SKB has chosen to build the repository using materials that are present naturally in the earth’s crust. By studying nature we can find out how copper, bentonite clay, rock and uranium dioxide behave both under different conditions and over different periods of time. By studying the radioactive byproducts of nuclear fission at Oklo, ancient natural cement in Jordan, natural copper in southern England, bentonite clay in Italy, concentrated Uranium deposits in Canada, and so forth, scientists understand the properties of these materials and phenomena that can occur over geologically long spans of time – longer than completely manmade experiments can cover. Analogues are often used to test models, which are in turn used to calculate the solubility of radionuclides in the groundwater.

The fuel will be placed in leaktight copper canisters with a cast iron insert. The canisters will then be transported down to a deep repository consisting of a system of horizontal tunnels at a depth of 400–700 metres in the bedrock.

The tunnels will be about 250 metres long and spaced at a distance of about 40 metres from each other. On the floor of the tunnels, deposition holes will be spaced at intervals of about 6 metres. The copper canisters will be deposited in the deposition holes and surrounded by a buffer of bentonite. When deposition is finished, the tunnels and shafts will be filled with a mixture of crushed rock and bentonite.

The leaktight copper canister will keep the spent fuel completely contained. The buffer of bentonite clay will protect the canister against corrosion attack and rock movements. If a crack should form in one of the canisters, the buffer and intact parts of the canister will prevent water from entering the canister. The buffer will also prevent radionuclides from leaving the canister. The rock will provide an environment where the function of the engineered barriers is preserved for very long periods of time. The rock and the great depth of the repository will keep the spent fuel isolated from man and the environment.

The copper canister that will surround the spent nuclear fuel is nearly five metres long and has a diameter of just over one metre. It weighs between 25 and 27 tonnes when filled with fuel. The outer shell consists of thick copper, and inside is an insert of nodular iron (a kind of cast iron) to provide sufficiently high mechanical strength.

As long as the canister is intact, no radionuclides can escape into the environment. Corrosion and mechanical forces due to movements in the rock are events that could lead to the breach of a canister. The canister is therefore made of materials that are designed to withstand such events. The canister is also designed to withstand major earthquakes following a future ice age.

Before the buffer is lowered into the deposition hole, the hole will be lined with blocks and rings so that a layer is formed between the inner walls of the hole and the canister. This layer is called the buffer, since its purpose is to dampen both mechanical and chemical changes in the rock.

The buffer consists of bentonite clay. It has three functions in the repository: to prevent corrosive substances from reaching the canister, to protect the canister from minor movements and to retard any radionuclides that might escape from a leaking canister.

The purpose of the rock is to isolate the waste. It is also supposed to provide a stable chemical environment for the canister and the buffer and protect them from whatever happens on the ground surface.

The groundwater moves in different ways in the rock’s fracture system. If radionuclides are dissolved in the water, they will accompany the movements of the water. The flow rate of the water varies both between different fractures and within a fracture, but is generally very low.

Virtually all radionuclides in the spent nuclear fuel can adhere to fracture surfaces, fracture minerals and the micropores inside the rock. Only iodine-129 and carbon-14 are somewhat mobile.






Reprocessing plants are not operated with the primary goal of separating plutonium from nuclear fuel – in a specifically plutonium-oriented fuel cycle, this may be the case; however, at present, the worthiness of reprocessing of used nuclear fuel comes primarily from recycling the uranium which makes up 96% of the fuel.

Even if no plutonium is extracted or recycled, recovering this uranium alone makes a vast difference to the long-term sustainability of the nuclear fuel cycle.

It is claimed that no commercially successful plutonium “breeder” reactor has ever been built – however:

* The BN-600 fast breeder reactor in Russia generates 600 MW of electricity, and has been in operation since 1980.

* The BN-350 in Kazakhstan first generated electricity in 1973, producing 150 MW, as well as 120 million litres of fresh water per day via desalination using the reactor’s heat. Whilst the project lifetime of the reactor officially finished in 1993, it continued to operate at reduced capacity until 1999 – a lifetime of 26 years.

* The Dounreay Fast Reactor in Scotland came online in November, 1959, producing an electrical output of 14 MW. The reactor was taken offline for decommissioning in 1977.

* The 233 MWe Phénix fast breeder reactor in France first supplied electricity to the grid in 1973 – it continues to operate to this day, with decommissioning expected possibly in around 2014.

* The 1242 MWe Superphénix fast breeder reactor, a full-scale nuclear power plant, completed construction in 1981 and was closed as a commercial plant in 1996.

* The Monju nuclear power plant in Japan, a sodium-cooled, MOX-fuelled fast breeder reactor, first acheived criticality in April 1994, and generates 280 MW of electricity. Whilst it was closed down for maintenance in 1995 following a sodium leak from the secondary coolant circuit, it is expected to be re-opened next year, and Japan has plans to construct more fast breeder reactors in the future.

It is claimed that major expansion of civilian nuclear energy will greatly increase the amount of nuclear material in circulation in the world – as though the “nuclear material” associated with nuclear power and nuclear weapons is the same thing!

The plutonium produced in power reactors is not weapons grade plutonium, and using such plutonium in a nuclear weapon is very difficult, and requires significant experience and knowledge in nuclear weapons physics – such technology is significantly harder to master than the already very difficult task of designing a nuclear weapon using plutonium.

It is claimed that he cleanup bill for a number of civilian and military nuclear facilities in the United Kingdom is estimated at more than 90 billion pounds – the nuclear weapons programs of the world’s nuclear weapons states, the Manhattan Project, and the Cold War arms race between the United States and the Soviet Union left a very significant legacy of radioactive wastes that were created and stockpiled, with little long-term attention to their safe disposal. Many of these wastes are not in forms which are easily managed, and cleaning them up will take much time and money.

But this is nothing to do with nuclear power – who estimates this cleanup bill, and how much of this cost is the nuclear energy industry responsible for? In the United States, and in other nations using nuclear power, the cost of final decommissioning and waste disposal is factored into the cost of marketed nuclear electricity.

It is claimed that “every stage in the nuclear fuel chain produces radioactive materials” – this is far from correct. It is only the operation of the nuclear reactor itself that “produces radioactive materials” – the radioactivity associated with uranium fuel production, uranium mining and mine tailings is all radioactivity that was originally, naturally present in the ground, and the radioactivity associated with used nuclear fuel and reprocessing wastes is radioactivity that was created in the reactor, along with the radioactivity of naturally occurring uranium.

Yes, exposure to high doses of ionising radiation can cause cancer, teratogenesis, and other deleterious effects on health. This is recognised by everybody – but these high doses of ionising radiation are not relevant to the context of the operation of nuclear power plants.

It is claimed that plant operators at Three Mile Island “fought to keep the reactor core from exploding” – this is simply ridiculous. A reactor core can not, does not, and will not explode – by what physical mechanism can it explode?

The small hydrogen explosion and hydrogen burn that occured within the reactor containment building had no significant engineering consequences – and there was never any danger of the overpressure from such a phenomenon breaching the containment vessel.

It is claimed that “operators released several hundred tons of radioactive gas” into the air, in order to prevent such explosion of the reactor.

It is estimated that a maximum of 13 million curies (480 petabecquerels) of radioactive noble gases were released in the course of the Three Mile Island event.

The noble gas – Krypton and Xenon – nuclides which are produced as fission products with any significantly large yield and which are radioactive, with a half-life so long as to be significant are Kr-85 (approx. 10 years), Kr-88 (2.8 hours), Xe-133 (5.24 days) and Xe-135 (9 hours).

If we assume the entire quantity of radioactive gas vented at TMI was the least radioactive of all the above, Kr-85, then the 13 MCi of radioactivity released corresponds to only 31 kilograms. So, not quite several hundred tons.

The average radiation dose to people living within ten miles of the plant was eight millirem, and no more than 100 millirem to any single individual. Eight millirem is about equal to a chest X-ray, and 100 millirem is about a third of the average background level of radiation received by US residents in a year.

Not a single person was injured, made ill or killed as a result of the Three Mile Island accident – and this is usually regarded as the worst nuclear reactor accident in history, outside the Soviet Union during the Cold War.

The Chernobyl No. 4 reactor experienced a massive power excursion, resulting
in a steam explosion, exposure of the reactor core and ensuing oxidation in
the extremely hot graphite moderator – nuclear grade graphite does not ignite
and burn per se, contrary to popular belief – resulting in a massive release of
radioactive material into the air. The reactor did not experience a “meltdown”.

Quantifying the effects of this event has proven to be difficult due to both
the widespread geographical influence of the radioactive contamination and the long time-scales involved in observing the potential long-term epidemiological consequences of exposure to high doses of ionising radiation.

The reactor was of a fundamentally flawed and unsafe design, and had had all safety systems shut off during a dangerous and unauthorized experiment.

On April 25, 1986, Chernobyl Reactor 4 was scheduled to be shut down for
maintenance. It had been decided to use this occasion as an opportunity to
test the ability of the reactor’s turbine generator to generate sufficient electricity to power the reactor’s water pumps, essential for safety systems, in the event of a loss of connectivity external electric power grid. The RBMK (Reaktor Bolshoy Moshchnosti Kanalniy) reactor requires water to be continuously circulated through the core, as long as the nuclear fuel is present.

A pair of diesel generators are normally used as a source of standby power, but these do not activate instantaneously. The reactor was, therefore, to be used to spin up the turbine, at which point the turbine would be disconnected from the reactor and allowed to spin under its own angular momentum, and the aim of the test was to determine whether the turbines running down could power the pumps while the generators were starting up.

The test was successfully carried out previously on another unit (with all safety provisions active) with negative results: the turbines did not generate sufficient power, but additional improvements were made to the turbines, prompting the need for a second test. As conditions to run this test were prepared, and the reactor electricity output had been gradually reduced to 50%, a regional power station unexpectedly went offline, meaning that the reduction in energy output needed to be postponed in order to supply demand on the electricity grid. The safety test was then left to be run by the night shift crew who would be working Reactor 4 that night. The power output of Reactor 4 was to be reduced from its nominal 3.2 GW thermal to 0.7 − 1.0GWth in order to conduct the test at the prescribed lower level of
power. However, the new crew were unaware of the prior postponement of the reactor slowdown, and followed the original test protocol.

The 135-Xe buildup in the reactor core makes it dangerous to attempt to operate the reactor a few hours after it has been shut down, without great care and understanding of reactor operation. Starting a reactor in a high-Xe condition requires pulling the control rods out of the core much farther than normal, to compensate for the nuclear ‘poisoning’ by 135-Xe. But if the reactor does achieve criticality, then the neutron flux in the core will become quite high and the 135Xe will be rapidly consumed by neutron-induced transmutation – this has the same effect as very rapidly removing a great quantity of reactivity control from the core, and can cause the reaction to grow too rapidly, with the potential to achieve prompt criticality. For this to be attempted in any reactor is a massive lapse in judgment on the part of the operators, and is indicative of extremely bad operator training, lack of safety culture and awareness, and a lack of design features which should make such a procedure impossible, or mitigate its risks.

All these factors were present at Chernobyl.

Nuclear physicists and engineers – most notably Edward Teller – discovered such safety concerns in the context of the early graphite-moderated reactors built at the Hanford site in the US for plutonium production for the Manhattan project, some 40 years before the Chernobyl accident. The early scaled-up graphite moderated nuclear piles at Hanford were arguably the closest the Western world has ever come to building a Chernobyl RBMK style reactor.
Nuclear poisoning due to 135Xe was first discovered in these first such reactors. Teller and his colleagues quickly discovered and pointed out the potential safety concerns associated with graphite-moderated water-cooled reactors having a positive void coefficient. As a result of his team’s persistent voicing of safety concerns over such reactor designs, Teller, most infamous for his tireless advocacy of a strong nuclear arms program and continued argument testing and development of nuclear weapons, in fact became known as “the reactor opposer” around this era, and the graphite-moderated design was never used again in the United States, aside from the nine original military reactors at the Hanford site.

It is exactly this situation which played a large part in the Chernobyl accident: about eight hours after the scheduled maintenance shutdown, workers tried to
bring the reactor to a zero power critical condition to carry out the turbine test, but because the core was loaded with 135Xe from the previous day’s operation, the reactor power output could not be increased above 30 MWt, approximately 5% of what was expected. The operators believed that the rapid fall in output was due to malfunctioning of one of the automatic power regulators, not because of fission poisoning.

In order to increase the reactivity of the reactor, automatic control rods were pulled out of the reactor beyond what is allowed under safety regulations.

Despite this breach, the reactor’s power only increased to 200MW, still less than a third of the minimum required for the experiment. Despite this, the reactor crew’s insufficiently trained and inexperienced management chose to continue the experiment. As part of the experiment, the water pumps that were to be driven by the turbine generator were turned on; increasing the water flow beyond what is specified by safety regulations. Since water absorbs neutrons, this further increase in the water flow necessitated the removal of the manual control rods, producing a very precarious operating situation where coolant water and nuclear poisons were substituting the role of most of the control rods of the reactor.

The unstable state of the reactor was not reflected in any way on the control panel, and it did not appear that anyone in the reactor crew was fully aware of any danger. Electricity to the water pumps was shut off and, as the momentum of the turbine generator drove them, the water flow rate decreased, decreasing the absorption of neutrons by the coolant. The turbine was disconnected from the reactor, increasing the level of steam in the reactor core. As the coolant heated, pockets of steam formed voids in the coolant lines.

The operators were careless and violated plant procedures, partly due to their
lack of knowledge of the reactor’s design, and lack of experience and training.
Several procedural irregularities also contributed to cause the accident. One
was insufficient communication between the safety officers and the operators in
charge of an experiment being run that night. The operators switched off many
of the safety systems, which was generally prohibited by the plant’s published
technical guidelines.

To reduce costs, and because of its large size, the reactor had been constructed
with no containment vessel, and only a large concrete biological shield atop the
reactor, primarily designed for radiation protection for plant personnel whilst
working atop the reactor. This allowed the radioactive contaminants to escape
unchecked into the atmosphere after the steam explosion burst the primary
pressure vessel, and the graphite core started to “burn” – not catching fire, but
oxidising as it was heated to great temperatures, facilitating the dispersal of
radioactive material into the atmosphere.

The Chernobyl disaster has absolutely no relevance what so ever to the question
of how much radioactivity could conceivably escape from the reactor, reactor
vessel and containment structure into the environment in the event of a
nuclear accident involving today’s civilian light water reactors, since the Chernobyl
RBMK reactor didn’t have a containment structure at all, amongst many
Given that the factors that contributed to the Chernobyl disaster have absolutely
no relevance whatsoever to the issue of nuclear energy, today, in the
Western world, by rights, on a rational, factual basis, the disastrous medical
consequences of the disaster have no bearing on the nuclear energy industry in
the United States or elsewhere.

Now, we have the claim that the Forsmark Nuclear Power Plant in Sweden “came within half an hour of a meltdown” in 2006.

On 25 July 2006, one reactor was shut down after an electrical fault. According to the Swedish Nuclear Power Inspection authority, SKI, the incident was rated 2 on the International Nuclear Event Scale.

According to Lars-Olov Höglund, a former construction chief at Vattenfall, it is the most serious nuclear incident in the world since the Chernobyl disaster and it was pure luck that prevented a meltdown.

Both SKI and the safety chief of Forsmark power plant disagree with that opinion and state that the incident was serious but the description provided by Höglund was incorrect and there was no risk of a meltdown.

The media hype in Sweden started with the “independent nuclear expert” Lars Olov Hoeglund stating that this was the “most dangerous event since Chernobyl” and “only luck saved Forsmark from a total meltdown”.

Originally titled “former construction manager” in media reports, Hoeglund has been promoted to “plant manager” and “CEO” of Forsmark in American and English media, and even head of the Swedish Nuclear Inspectorate in German media reports.

In reality, he was never employed by Forsmark. He was “construction manager” for some years at a Vattenfall mechanical engineering department.

He did spend some years at the Forsmark site as a constractor, but only at the waste storage and disposal facility, unconnected with the nuclear power plant.

Maybe more importantly, he has for years been locked in legal conflict with Forsmark (as well as Ringhals NPP), regarding some jobs that his consultancy tendered on but did not get selected for. Apart from this, he has, through legal appeals in environmental courts, delayed a number of projects at both Ringhals and Forsmark.

His claims regarding the shutdown at Forsmark in 2006 have never been substantiated by any credible source.

Regarding the “near miss” at Davis-Besse in the US in 2002, a breach in the Davis-Besse reactor’s corroded pressure vessel head would have
contaminated the reactor’s containment building with reactor coolant from the primary loop. All the radioactivity in such coolant would be contained within
the containment vessel. Emergency procedures would have protected the reactor from core damage, as with any Loss of Coolant Accident. Even the worst
possible situation in this case, a loss of reactor coolant, is far from being a “major catastrophe”, although it is a serious reactor incident. Since the carbon
steel reactor vessel is lined on the inside with a further inch of stainless steel, the corrosion of the outer carbon steel part of the reactor head, caused by a small,
persistent leak of boric acid, could not have completely breached the integrity of the pressure vessel, as stainless steel could not be corroded at all in such a way.

If the vessel was breached, in such a near-impossible manner, then the plant would be shut down, and would be offline for some time. The reactor may have even been, in the worst-case scenario, written off. But no radioactivity would possibly be released into the environment, thanks to the containment vessel.

It is claimed that under the Global Nuclear Energy Partnership, Australia is being promoted as the site for disposal of the world’s nuclear waste, and that sites are being selected for such.

There is simply no credible evidence what so ever that this is a widely promoted ideology, and especially not that it is widely accepted.

It would be kind of like thinking that Saudi Arabia has some kind of obligation to take the world’s production of carbon dioxide, for geosequestration, because they’re one of the leading producers of oil, wouldn’t it?

As the DOE themselves put it, The Global Nuclear Energy Partnership has four main goals. First, reduce America’s dependence on foreign sources of fossil fuels and encourage economic growth. Second, recycle nuclear fuel using new proliferation-resistant technologies to recover more energy and reduce waste. Third, encourage prosperity growth and clean development around the world. And fourth, utilize the latest technologies to reduce the risk of nuclear proliferation worldwide.

Through GNEP, the United States will work with other nations possessing advanced nuclear technologies to develop new proliferation-resistant recycling technologies in order to produce more energy, reduce waste and minimize proliferation concerns. Additionally, the partner nations will develop a fuel services program to provide nuclear fuel to developing nations allowing them to enjoy the benefits of abundant sources of clean, safe nuclear energy in a cost effective manner in exchange for their commitment to forgo enrichment and reprocessing activities, also alleviating proliferation concerns.

The nuclear fuel cycle is not heavily dependant on cheap fossil fuels – certainly not any more dependant on fossil fuels than the production of fossil fuels themselves, or the use of solar, wind, or other energy systems, and the life-cycles associated with them.

The idea that whole-of-life-cycle analysis can demonstrate that nuclear energy
is unsustainable, both on an energy intensity basis and a greenhouse gas intensity
basis, is based on a very limited set of highly dubious science, which has
been widely rebutted, and found to be irreconcilable with the body of scientific
literature established relating to the energy and greenhouse gas intensities of
the nuclear fuel cycle. This will be discussed in greater detail in a later section.
It should not be unreasonable to believe that one day, we can as a society dispense
with fossil fuels entirely, and use clean wind, nuclear and solar-generated
electricity to supply the energy inputs associated with mining and processing
raw materials such as Uranium, Aluminum or Silicon, and the construction of
energy infrastructure, with electricity, and advanced thermochemical processes
used to generate Hydrogen, as transport fuels, thus leading to solar, nuclear or
wind-based energy generation which truly does not produce any greenhouse gas
emissions at all.

The Rossing Mine in Namibia has a Uranium concentration in the ore of about
350 ppm, and produced 3037 tonnes of Uranium in 2004, which is sufficient
for about 15 GW-Yr of electricity with current fuel cycle and power reactor
technology. The energy used to mine and mill this Uranium is about 30 MW-yr,
thus corresponding to an energy gain of about 500.

Extrapolating this, for a Uranium mine to produce no net energy gain, it would
be required to have a Uranium concentration in the ore of no more than about
0.7 ppm. Given that the average concentration of Uranium in the Earth’s crust
is 1-3 ppm, one can expect that the majority of exploitable Uranium reserves
can reasonably be expected to produce a non-trivial energy gain, even utilizing current reactor technologies and current, inefficient 235U based nuclear fuel

As I mentioned above, the energy inputs that go into the nuclear fuel cycle don’t
implicitly need to come from polluting, unsustainable fossil fuels. As the rest
of society moves away from fossil fuels to an energy mix of solar, wind, nuclear,
hydroelectric and other sustainable energy sources, so will the mining industry.
In fact, Australian hot fractured rock geothermal energy company PetraTherm
recently signed a memorandum of understanding to supply geothermal electricity
to South Australia’s Beverley Uranium mine by late 2009.

The EURODIF Uranium enrichment plant in Pierrelatte, France receives its entire energy supply from the nearby large Tricastin Nuclear Power Plant, on the same site – no indirect greenhouse gas emissions here, either.

To consider another example, the United States Enrichment Corporation’s Uranium
enrichment plant near Paducah, Kentucky operates using electricity – a
significant amount, about 3 GW at peak operation capacity – generated by the
Tennessee Valley Authority, and supplied via the normal electricity grid. The
TVA supplies energy to the electricity grid using a diverse mix of energy sources
– 11 fossil-fuel plants, six combustion turbine plants, five nuclear reactors and
twenty-nine hydroelectric dams. In 2006, 35% of TVA’s generation capacity –
which we can assume corresponds to 35% of the energy supplied to the Paducah
enrichment plant – was provided by these non-greenhouse intensive hydroelectric
and nuclear generation technologies.

There are a number of publications by Storm van Leeuwen and Smith (hereafter,
SLS) that have received considerable attention because of these authors critical
attitude regarding nuclear power.

There have been scientific counter arguments and rebuttals to their work published
by the World Nuclear Association, with a rebuttal by SLS, and by physicists
from the University of Melbourne, with a rebuttal by SLS, a response by
the authors; a second rebuttal, and a second response. The ISA report mentioned
above is also particularly critical of the work of van Leeuwen and Smith.
The arguments put forward in some of these exchanges are nothing new.

The study of Storm van Leeuwen and Smith neither states energy nor greenhouse
gas intensities, but instead presents temporal profiles showing break-even points
with gas-fired power plants. ISA, therefore, have therefore extracted all energy
coefficients from the study and applied them to a hypothetical nuclear fuel cycle
in Australia. For ores of 0.15% grade, they obtain energy and greenhouse gas
intensities of 0.66 kWhth/kWhe and 212 g CO2e/kWhe, respectively. If such
rich ores are assumed, the construction and decommissioning of the power plant
are the main contributions to energy and greenhouse gas emissions.

If lean ores are assumed (0.01% U), the situation changes drastically: Mining,
milling, and the clean-up of the mine site become the main components of the
total energy and greenhouse gas intensities. The energy and greenhouse gas
intensities are 1.63 kWhth/kWhe and 527 g CO2e/kWhe, respectively.
From a review of the literature concerning the energy intensity, sustainability
and greenhouse gas emissions intensity of nuclear energy over the whole of life
cycle, one notes that there is considerable agreement between numerous different
bodies of work, such as Vattenfall’s environmental product declarations, the
work of the University of Sydney ISA group, the World Nuclear Association,
and independent physicists from the University of Melbourne, just to name a
few, and they all demonstrate findings which are for the most part completely
inconsistent with the work of van Leeuwen and Smith.

Although the greenhouse gas emissions from the nuclear fuel cycle, even with low-grade Uranium ores, remain in the same order of magnitude as other sustainable non-fossil energy sources, this still ignores the point, as previously made, that the nuclear fuel cycle does not implicitly require fossil fuel generated energy to supply these energy inputs – although at present the nuclear fuel cycle
generates a comparatively tiny amount of greenhouse gases, just as does wind,
solar or hydroelectric energy – as clean non-fossil energy sources are developed
further in the future, this will change, and all energy generation will potentially be one hundred percent GHG emission free.

Sure, geothermal and hydro are baseload sources of electrical generation – hydroelectricity, along with nuclear, is one of the largest sources of clean electricity in the world. But if you don’t have the right geology in the right places, if you don’t have the rivers and water resources to play with, then hydro and geothermal are of limited use. Cogeneration – combined heat and power – is usually realised using natural gas, and whilst it realises an increase in the overall efficiency of energy conversion, you’re still burning a greenhouse intensive fossil fuel!

Wind turbines: Running some numbers.

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I recently came across the website of EcoTricity, a firm in the UK who are quite proud of a number of wind turbines they’re building. (Thanks to Atomic Insights for the tip on this story.)

If we look at some of their construction photos, we are reminded that in practice, every construction project of this sort involves vehicles powered by fossil fuels, raw materials such as concrete, Aluminium and steel, all produced using various energy inputs, many of which come from fossil fuels.

In fact, wind turbine energy is associated with whole-of-life-cycle greenhouse gas emissions of around 20g CO2 equivalent per kWh of electrical output – this is not zero, but like the other clean alternatives, it’s clearly far better than coal-fired electricity, for example, which is the most common and the most polluting electrical energy source, with a whole-of-life-cycle greenhouse gas emissions profile of about 1000g CO2-eq./kWh.

This latest turbine installation – the company’s biggest to date – was built in August this year, and consists of three massive turbines with a nameplate capacity of 2 MW a piece. We are told that this corresponds to 15 million units of actual generated capacity, but unfortunately, they seem to have neglected to tell us exactly what this unit is.

These 2MW nameplate turbines have a hub height of 78 m and a rotor diameter of 82 m.

It is claimed that this project will save the emissions of 15,408 tons of potentially dangerous CO2 annually. Sounds good.

However, if we assume that this wind energy can directly displace the same amount of coal-generated electricity, that these energy systems have whole-of-life-cycle emissions characteristics as I noted above, and assume that the wind turbines have a capacity factor of say 20%, then a simple calculation of the generating capacity required to displace that amount of GHG emissions seems to indicate that 6MW of installed capacity just isn’t enough, and that 9MW of capacity is actually required.

I’m not an expert on engineering wind energy, and finding the best site, and so forth, but I think a capacity factor reaching 30% – which is what they’d need to have, unless the coal capacity they’re displacing is really, really inefficient, would be extremely difficult to attain.

I wonder where the discrepancy arises?

To further put the scale of such a project in context, these three turbines, operating with say a 20% capacity factor, generate around 1.2MW of electricity – three thousand such turbines will generate 1.2 GW. This sort of power output can be achieved by one single modern nuclear power reactor, with a capacity factor of say 92%, with a nameplate capacity of 1.3 GW. Today’s nuclear generating plants, with two or more units on site, typically generate far in excess of that.

Written by Luke Weston

October 8, 2007 at 12:39 pm

Life-cycle analysis of energy intensity and greenhouse gas intensty of nuclear energy.

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This is a very, very comprehensive and useful work – and especially good literature review – of Whole-of-Life-Cycle analysis of the energy intensity and greenhouse gas intensity of nuclear energy.

There’s one key point that stands out specifically, again and again when reading it.

We’ve come to the same conclusion before, and most of you reading this blog probably know exactly what I’m talking about, but let’s just spell it out:

Jan Willem Storm van Leeuwen and Philip Smith are WRONG.

Written by Luke Weston

July 29, 2007 at 3:17 pm