Emissions Nuclear

Australia will break the world’s carbon budget

As David Spratt explained recently, the Australian Government is keen to boost its carbon mitigation credentials by claiming we are doing our part to avoid dangerous climate change. Australia’s current target — 5 to 25% reductions by 2020 on 2000 emissions levels, and a 60% reduction by 2050, sounds decent enough and will require transformative changes in energy use if it is to be achieved. Other developed countries have similar targets — Obama’s aim for the USA, for instance, is to get back to 1990 levels by 2020 and 80% lower by 2050.

We’re doing our bit, perhaps. But is this bit enough, or fair, or feasible, given the need for strong global cooperation and Australia’s current rejection of the nuclear energy option? No, no and no.

The problem with our emissions reduction target boils down to historical and current inequities. Let’s consider the year 2000 baseline — in that year, human-caused CO2e emissions were about 34 billion tonnes (Gt). For a world population of 6.5 billion people, that’s about 5.2 t per annum for each and every man, woman and child on the planet. What is Australia’s per captia emissions, relative to that world average? At about 25 t, it’s around 5 times larger. Other countries in the developed world range from about the same (USA, Canada) through to about half (UK, Germany) or even a third (France and Sweden — go those nukes and hydro!). As you can imagine, the developing world’s average is far lower — about 4 t for China, 2 t for India, 1 t for Bangladesh, etc.

Okay, I’m going to switch units on us now. For reasons of convenience that will become apparent in a moment, let’s re-express these figures in terms of carbon (C) alone. To do this, we can (roughly) divide the above figures by 3.66 (i.e., 44/12, being the molecular weight of carbon+oxygen+oxygen divided by that of carbon alone) — I’m subsuming methane, nitrous oxide, CFCs etc. in this approximation. So we have 9.3 GtC for the world in 2000 at a per capita rate of 1.4 tC and Australia at 6.8 tC.

Now, in a recent issue of Nature, there were a number of useful papers which explored the idea of total global carbon budgets. David Adam from The Guardian has done a good write-up of them here, and George Monbiot has reviewed the implications of their results for fossil fuel use, asking what it means in terms of how much coal, oil and gas we can afford to burn (answer: we can afford to burn only 33 to 61% of known [proven + provable] fossil fuel reserves between now and eternity). In essence, to have a 50% chance of avoiding 2C of global warming above pre-industrial levels  (already a difficult challenge for adaptation), humanity can afford to emit only 310 GtC between 2009 and 2049, and a maximum of 400 to 500 GtC at any time between now and the point at which humans leave the planet (in whatever way this occurs). For a ‘good’ (>75%) chance of avoiding +2C, the carbon budget tightens to 190 GtC between 2009 and 2049.

Let’s assume the human collective throws caution to the wind (hey that’s a good bet based on current policies), and we shoot for that 50% chance of avoiding +2C. Under this scenario, we’ve got a 40 year carbon budget of 310 GtC, or about 7.75 GtC per year. If we were to lock emissions at 2000 levels, we’d get to 372 GtC, which already breaks the budget — and emissions have been growing by a few percent each year since that date, so we’ll be well over at this rate. Next, let’s assume that we instead peak in 2015 at 11.7 GtC (based on 2% growth from 2000 to 2008, 1% growth from 2009 to 2015) and then cause global emissions to decline at 1% pa from 2016 to 2019, 4% pa from 2020 to 2030, and 3% pa thereafter. This scenario assumes that we make the big inroads in the decade 2020 to 2030 (emissions in 2030 = 7.2 GtC) after ‘building momentum’ during the decade 2010 to 2019 (emissions in 2019 = 11.2 GtC), and it manages to stay within our 40-year budget of 310 GtC. The result is global emissions in 2050 being 4 GtC, or a per capita rate (assuming a population that has stabilised at around 9.5 billion people — mid-range UN projection) of 0.42 tC per annum. That’s a global carbon emissions reduction of 57% in 2050 compared to 2000 levels — almost spot on the Australian target of 60%!

Trouble is, Australia’s emissions were 6.8 tC per capita in 2000. If we are to contract to the global average by 2050 of 0.42 tC per person per annum, we’ll need to reduce our emissions by 94%. Not 60%, which is the current policy. This of course presumes that a global climate agreement emerges from the principle of shared and differentiated responsibility; akin to a contraction-and-convergence approach. Whilst I acknowledge that a C&C agreement is highly unlikely in its purest form, I still suspect that if we are indeed to achieve a peak CO2e concentration of 450 ppm (or lower), it will be on the basis of some agreement that is closer to C&C than anything resembling a full retention of historical advantages — which is what the current Australian policy implicitly assumes.

Of course if you want a 75% chance of avoiding +2C, the figures become tighter (about 80% global reduction by 2050 and 97% for Australia). If you take into account slow feedbacks, which imply a climate sensitivity that is higher than the mid-range estimate of 3C, or conclude that +2C is too much global warming, then the permitted carbon budget contracts still further — this is why Hansen and others are talking seriously about negative net emissions (with the help from geoengineering) well before 2100.

The bottom line: Australia’s target of 60% reduction by 2050 is not supportable on the basis of climate science, and should be rejected. A reduction of around 95% by 2050 implies a total decarbonisation of our electricity, construction, manufacturing and commercial sectors and transportation system, and a huge reduction in our agricultural sector. It will require something like this:

1. Early improvements in energy efficiency and conservation, and a substantial expansion of our use of renewable energy.

2. Large-scale adoption of nuclear power (around 75 to 100 GW will probably be required by 2050) based on fast spectrum and thorium reactors.

3. Metal-fuelled vehicles [combusting boron or aluminium in pure oxygen] (and perhaps a useful contribution of battery electric vehicles).

4. Plasma torches for municipal solid waste recycling.

5. Halt to deforestation (land clearing) and improvement in soil carbon retention.

6. Reduction in livestock methane emissions (probably by a combination of reduced stock and genetic engineering of methanogens).

All difficult, but all possible. My mantra is this: let’s be completely honest about facing up to both the carbon targets required and the means required to achieve them. The challenge, in terms of emissions reduction, is enormous. Given the magnitude of this extraordinary task, the means to get there will be only remotely possible if nuclear power plays a major role. If you are anti-nuclear, get over it, unless you are willing to leave a wrecked climate system as your legacy.

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By Barry Brook

Barry Brook is an ARC Laureate Fellow and Chair of Environmental Sustainability at the University of Tasmania. He researches global change, ecology and energy.

88 replies on “Australia will break the world’s carbon budget”

a good outline of the challenges but your bottom line solutions could be broken down to much simpler outcomes;
1) immediate improvements in energy efficiency and conservation especially reducing electricity and oil consumption.
2)replacing all coal fired electricity and other uses of coal with carbon free sources, or NG and reducing overall natural gas consumption.
3)replacing oil based transportation with chemical or mechanical energy storage recharged by carbon free energy
4) re-cycle as much biomass as practical to generate gas/ethanol/bio-diesel
5)convert agriculture to a net carbon sink

This focuses on the areas that need solutions, why limit any one solution to any one technology, probably need more than one technical solution for each of those five points.

For example, steel manufacture may be replaced partly by electric arc recycling and using NG instead of coal.Biomass and blast furnace slag, may be able to replace coal used for cement manufacture.Transportation may have a range of solutions, compressed air, chemical batteries flywheel storage as long as the energy comes from non FF.

All plans are going to need some NG at least until 2050.


Neil, your points are more general yes, but they are not ‘simpler’ — just vaguer. But I agree that your 1-5 are also an acceptable way to point to what is required, apart from the NG part (that’s out!). I still think that we will need to end up ‘picking winners’, even if it’s to give them an initial boost (a good example being a demonstration commercial-scale IFR plant required for NRC certification, and an RD&D boost to LFTR to get these rapidly to commercialisation).

You see, if we are targeting a 94 to 97% emissions reductions by 2050 then we can’t burn ANY fossil fuel derived natural gas by that time, and will need to have completely phased it out by the 2040s at the latest. If you disagree with the science and ethics behind the 94-97% reduction numbers, then you can have your NG — otherwise it’s up to technologies like the LFTR and/or ‘overbuilding’ IFRs in combination with boron-reduction and desalination during off-peak times, for load following.


Realistically it’s going to be a massive job to eliminate in 41 years all coal and nearly all oil. This is going 90% of the way,
removing that last amount of FF is going to be very expensive, it may be cheaper to convert agriculture into a net carbon sink(re-forestation, increasing soil carbon),and using some biomass as a carbon sink.
I don’t think we have to do too much about oil, except insure that present vehicles are as efficient as possible, it’s going to be priced out of the market by 2050 without any political effort.
The big fight is going to be to get rid of coal especially coal fired electrical energy, that’s where the political fight is needed.
You could choose to take on all FF energy and all electricity generators(except Snowy and Tas hydro) but that’s a good way of being marginalized, until nuclear and renewable electricity is in place NG can help with many solutions in the next 40 years, plenty of time for longer term solutions to replace NG to be developed.
Going to 90-95% reduction by 2050 is better than doing nothing about coal or allowing coal to delay another 20 years with CCS promises. We need to cut the head off the coal snake as soon as possible, coal fired electricity is the head.
I would prefer to see all coal generated electricity replaced by mainly NG ASAP, as that would give a good long term economic incentive for nuclear and renewables to replace most NG usage.
Remember it’s not how much CO2 we release in 2050, its how much we release from now to 2050, NG peak generators can be built quickly.They only release CO2 when in use, coal plants release CO2 24/7.


You make a good point about trying to use agriculture as a short-term offset to NG, and the small amounts that will be used in peaking operations.

We definitely agree that the priority order is coal first, NG second, with oil mostly sorting itself out due to supply problems. I just think that we can, with sufficient effort, get rid of coal by 2030-2040 and NG completely by 2050 (perhaps replacing fossil-fuel derived NG with a combination of biogas [from agricultural waste and microalgae] and syngas [from plasma burners]). Eliminating NG by 2050 is of course likely to be impossible without a large contribution from nuclear power.


Barry, can syngas from plasma burners be used to provide peaking load (ie displace NG)?


Yes, and I think this is a great use for it, along with production of plastics and other current derivative products of petrochemicals (microalgal diesel residue is also apparently good for plastics production). Tom Blees argues that MSW, converted to syngas using plasma torches, could supply a large amount of electrical power via gas turbines.


On fossil fuel use there are some possible twists. According to some pundits we can expect a crisis in liquid fuels (petrol, diesel, jet fuel) with a decade. Whether that slows total coal use or promotes coal-to-liquids is unclear. I believe Australia should promote compressed natural gas as a fuel initially in heavy vehicles. To conserve the resource the use of gas in electrical generation should be limited to balancing of wind power. I suggest a ratio of say one kwh gas fired to three or four kwh wind.

A year or so ago Australia’s black coal exports were four tonnes for every tonne used domestically. I think a fair sacrifice would be that importers and locals share the pain with annual cuts of say 2-3%. I think those coal import countries will soon find that alternative sources will peter out.

On ‘contraction and convergence’ generally I unsure whether some populous countries deserve the same per capita allowance. They are to some extent the architects of their own misfortune. This issue is a sleeper for now.


I think it’s very important to distinguish between liquid fuels and electrical generation.

Given the centralization of the problem: coal plants, it’s relatively ‘easy’ in a way to come up with a solution to this stationary problem of CO2. Nuclear, obviously *would* shutdown every coal plant in Australia.

But liquid fuels, minus the development of serious electrical/battery storage systems, is a far harder thing to deal with. We are talking about synthetic fuels which require a lot more energy to create than each particular fuel ‘carries’.

They are, or should be, separate discussion.



It is definitely more technically difficult, but easier politically, because oil will run out, so people will be forced to change.
just hope any synthetic fuels are not CTL or GTL.

If battery/ electric replaces most commuting trips and within city truck traffic the limited amount of biofuels could be used for aircraft and longer distance, with electric rail replacing most of these longer trips( obviously not overseas).


For sure. But bio fuels as we do them now are politically very risky. Industrial bio fuel from non-food sources I have less of a problem with.

But ramping up to serious bio fuel usage is a decade away. The same with synfuels like methanol and di methyl ether.

Fossil fuel for autos is not going away soon. It’ll be price that begins to spike IF the world ever recovers from this near-depression we are in.



Barry Brook – Not a bad article until you got to the end – this is what I have a problem with:

“My mantra is this: let’s be completely honest about facing up to both the carbon targets required and the means required to achieve them.”

Since when did the end justify the means?

“The challenge, in terms of emissions reduction, is enormous. Given the magnitude of this extraordinary task, the means to get there will be only remotely possible if nuclear power plays a major role.”

The real challenge is our unwillingness to change even one aspect of our lives and still decarbonise. You are committing us to attempting to maintain our incredibly energy intensive lifestyles, which only 20% or so of the Earth population enjoys, by deploying anything and everything that you think will achieve it.

If, as you say, we aggressively practice energy conservation and efficiency gains this brings us into the easy capture range of an all renewable solution that does not need nuclear at all – would you be prepared to accept this?

“If you are anti-nuclear, get over it, unless you are willing to leave a wrecked climate system as your legacy.”

Do you really believe this? So anti-nuclear people like myself are now cast as climate wreckers! Do you honestly think that this is a rational basis for discussion?

The problem is that your solution ‘may’ save the climate but leave dangerous nuclear waste plus many unstable countries with nuclear weapons that they can, and will use to gain access to increasingly scarce resources.

The mantra of anything goes as long as we save the climate is potentially a very dangerous strategy.


David MacKay seems to have a realistic take on whether renewables will be enough. How many of today’s middle class are prepared to live with hair shirt solutions? How will industries like metal production and fabrication cope without power on demand?


David MacKay is presenting future replacement of FF by non-CO2 emitting energy resources in the UK, 240,000 km^2 islands, certainly having a very high population density and rather poor solar energy resources.
He has made some assumptions for example about wind energy and how many wind turbines may be tolerated, that could be challenged, but his conclusion that the UK cannot easily be energy self sufficient and would have to import either solar energy form Africa, or uranium from other countries is probably not too far wrong.
This is certainly not relevant to Australia or virtually everywhere else in the world except Europe.

I fail to see how replacing cheap coal fired electricity is going to have much of an impact on the average wage earner’s electricity bill of about $1000 a year, to ensure that was all from renewable energy would cost another $500/year( 1% of the average income). Is that going to bring out the hair shirts?

Any reduction in coal use or CO2 tax or cap will have a very big impact on aluminium costs, we have to accept that aluminium is going to go up in price everywhere, that’s OK essential uses are not very price sensitive. Other metal producers such as copper and nickel often shut down when costs exceed prices, this can happen with aluminium refining but eventually the world will need aluminium and will pay the same cost that everyone else pays for electricity.


John Newlands – “David MacKay seems to have a realistic take on whether renewables will be enough”

As Neil said David made some assumptions that seemed questionable to me. Also there seems to be the unspoken assumption that energy conservation and efficiency = hairshirt which is patently not true however is often used as an argument against renewables.

Both David Mills here ( and Mark Diesendorf (Saddler H, Diesendorf M & Denniss R 2007, ‘Clean energy scenarios for Australia’, Energy Policy 35(2):1245–56.) present very different scenerios that involve neither hairshirts nor nuclear.


Have you considered advising MacKay of the assumptions you think are questionable, either as errata or on his metafaq page? He invites such feedback, and seems very responsive.


He is aware that taking the average wind speed underestimates power, he also thinks the NIMBY factor will limit wind farms to << than 10% of UK, this is why he assumes off-shore could contribute more. Some of his other assumptions about needing more turbines that are installed world wide has now been overtaken by growth in installed wind in the last 2 years


I believe him when he says total land area available for wind is << 10% of the UK. That definitely sounds right.

And while using the average windspeed underestimates the power, he also overestimates the power by assuming a wind turbine can capture power from wind at all speeds, instead of just within their operating windspeed range. Its a reasonable approach to take when just looking for rough numbers on the size of the resource, and overall it looks like he has been generous in his estimate of the wind resource, not niggardly.

I don’t see how the building of more wind turbines in the last two years affects the size of the available wind resource, either. Thats a number he uses for illustrative purposes, but doesn’t bear on his estimate of available power.


John and Neil,

I’ve not looked closely at how MacKay treats wind. How does he treat off shore wind?


Hi Edner, MacKay actually cites David Mills as one of his sources for calculating area required for CSP.

I think MacKay has got a lot right, no hair shirt required. But I take your point, we can consume a lot less while increasing our total wellbeing. Re my point about China going backwards by replacing bikes with cars to deliver mass traffic congestions, slow traffic overall and produce first world diseases (cardio, respiratory, obesity, diabetes etc.)


Mackay deliberately avoids costs on his plans — they are physics based calculations, and of course on that basis Australia, with a huge area and sparse population, can ‘romp this in’. When costs are accounted for, especially in regards to energy storage, backup and re-generation (plus required technical innovation for large-scale storage) and grid connection and variability management, it becomes a whole ‘nuther ball game.


But not as expensive at other wasteful and damaging endevours. The chart linked to below, shows Britain’s cost of one of the plans (includes nuclear and CCS combined at about 20% , but others don’t so may be cheaper or more expensive to some fraction). It shows that the overall costs of one of Mackay’s plans is a faction of their bank bailouts or contributin to war.


“If you are anti-nuclear, get over it, unless you are willing to leave a wrecked climate system as your legacy.”

Do you really believe this? So anti-nuclear people like myself are now cast as climate wreckers! Do you honestly think that this is a rational basis for discussion?

Yes, exactly. That really is the way I now see it. I’m reminded of the Edmund Burke quote: “All that is necessary for the triumph of evil is that good men do nothing”.

To paraphrase Burke, with apologies:
“All it will take for climate change to create havoc, wreck our civilisation, and condemn a large fraction of species to extinction, is for good men to block real solutions like nuclear power.”


I agree with Barry (BTW…Barry, your email seems not to work, what IS your email?).

Many of us, myself included, came from a renewable-advocacy activist background. We realized that not only will renewables be MORE expensive, but that its’ based on energy-starvation (trying to less and less of it) and that it would not at all, shutdown coal and NG plants. This is what convinced me that nuclear is a better alternative. That supporting the “all renewables” paradigm was in fact supporting fossil, since all renewables need an almost KW-per-KW backup of real on-demand power for wind and solar.

Every national ‘alternative’ energy plan *actually implemented* (Danish, Spanish, German, etc) that goes into double-digit % of renewable capacity includes MORE fossil burning and in the case of Germany, vast amounts of more coal.

Now, renewables *could* work with nuclear, instead of fossil we build baseload nuclear and let renewables try to handle all the intermediate and peak loads. That would be worth a shot.



David Walter – “That supporting the “all renewables” paradigm was in fact supporting fossil, since all renewables need an almost KW-per-KW backup of real on-demand power for wind and solar.”

Except that they don’t. CSP can store heat very economically and wind only needs 1/5 or so ‘backup’ if it is well dispersed. In fact it needs about the same amount of ‘backup’ both peaking power and spinning reserve that baseload nuclear needs. Peaking power can run on stored hydrogen or waste biomass syngas. The hydrogen could be produced from solar plants as not operating at night does not matter as long as there are sufficient stores. The hydrogen will also be used in fuel cell cars that will inevitably be marketed in the near future.

“Every national ‘alternative’ energy plan *actually implemented* (Danish, Spanish, German, etc) that goes into double-digit % of renewable capacity includes MORE fossil burning and in the case of Germany, vast amounts of more coal.”

Only if you have a large proportion of baseload that you cannot change with the wind. Also Germany has a lot of marginal wind that distorts their figures. Have a look at Spain recently where 43% of their demand was satisfied by wind – that resulted in major savings.

“Now, renewables *could* work with nuclear, instead of fossil we build baseload nuclear and let renewables try to handle all the intermediate and peak loads. That would be worth a shot.”

So nuclear would be limited to less than 30% of demand as this is as much as we would want. However on a lot of days in a free market, wind or solar would displace the nuclear perhaps making it largely uneconomic. Why do we need nuclear as a baseload? Again dispersed and networked renewables can do baseload however as they are flexible they can also do peak and intermediate as well. Nuclear only does baseload economically. You can run them as load followers however then they are intermediate and only run for 4 hours or so per day making them uneconomic except for government owned power companies. You can find make work for them like desalination or plasma torches however then there are control issues to solve here as how do you switch off the make work task quickly enough to switch the nukes back onto the grid?


Ender, CSP has never been real base load. The longest proposed “storage” using hot sodium salt is going up now in California. It will provide 7 additional hours of power at about 30% of rate load.

At a recent solar conference here, I asked them why “only 7 hours”. The answer: it’d cost too much to make it run for the 20 hours over peak MW rating…they’d have to build it out too much.

I asked if there was “anyway it could?”. The answer” yes, “give us the ‘federal support’ and we can do it, but even we think that would be too much to ask”.

The idea that you can economically build out renewables like solar thermal and wind cheaply enough…for base load…which is all day, everyday, at a minimum of the system’s load, with renewables is proven false by the planners/ISOs etc in very pro-renewable countries like Denmark and Spain: they have no plans to eliminate on demand power, period. Thus they both build natural gas plants as part of their ‘renewable’ programs.



Dear David,

I think solar thermal with storage is already operating in Spain at Andasol 1 and there are plans to increase it considerably in subsequent stages. It was designed (as was the Californian facility you referred to) to overcome the variations in sunlight within one day and transfer power to the high late afternoon/early evening periods of demand. They were not designed to be the real base load you refer to.

Solar thermal can be designed to replicate real base load, i.e. all day (which it has done as per above) and everyday. The only problem to achieve ‘everyday’ is to store potential energy in some form (including molten salt) for more than a few hours. The current well tried and costed way to store potential energy is pumped hydro.

Less well tried or costed is the storage of molten salt for more than a few hours. I don’t know what the cost of storage would be, and how it would increase with the time stored. I note that the people you spoke to were of the opinion that the cost would be “high”.

Sandia labs (in October 2006) at comment on this way of storing heat. Cherry picking from that short document their third and final paragraph reads:

“The uniqueness of this solar system is in de-coupling the collection of solar energy from producing power, electricity can be generated in periods of inclement weather or even at night using the stored thermal energy in the hot salt tank. The tanks are well insulated and can store energy for UP TO A WEEK [My emphasis]. As an example of their size, tanks that provide enough thermal storage to power a 100-megawatt turbine for four hours would be about 30 feet tall and 80 feet in diameter. Studies show that the two-tank storage system could have AN ANNUAL EFFICIENCY OF 99 PERCENT. [Again my emphasis, but I am not sure I know what this 99 percent means – heat in to heat out?]”

Kind regards,

David Murray


David W and David M,
Why would you want solar to have enough storage for base-load. Solar can provide peak load with a few hours storage, this is much more valuable, off-peak is low priced( wind, nuclear and coal).NG can be used as base-load but makes a lot more by only using for peak demand. The exceptions are oil fired steam turbines that have been converted to NG.


Dear Neil,,

“Solar can provide peak load [demand] with a few hours of storage…”

Yes, I agree with this 100 %.

Wind can meet off peak load demand quite adequately.

There is a predictable minimum (base load) demand which is there all day, every day.

Some people (me excluded) argue that this must be met by the supply of real base load power, which can provide this amount of electricity (no more, no less) all day, every day. They argue further that supplying this sort of electricity can be done very cheaply. Normally coal and nuclear are seen as the technologies appropriate for this role. Gas seems to be able to do this but at greater cost. Gas is also dispatchable – which coal and nuclear seem not to be.

The argument above is wrong because if sufficient stored energy ( pumped hydro or molten salt) is available and electricity can be produced from that stored energy at a cost lower than from coal or nuclear it is the appropriate [base load]energy source.

“Why do you want solar to have enough storage for base load [as opposed to peak and off peak load]?”

I want wind or solar or any other CO2 free electricity source (or at a push low CO2 gas) to replace high CO2 sources. This can be done if energy from these intermittent sources can be stored. Currently wind and pumped water are the best proven and costed combination of energy and storage to meet this need. If CSP with pumped water or CSP with molten salt prove to be cheaper than wind with pumped water then that combination should be used. In practice of course both energy sources will have more and less favourable locations and therefore rising costs – which would imply using both wind and CSP from the appropriate lowest cost sources.

Kind regards,

David Murray


Great discussion! Yes, I can see CSP for intermediate and peak load.

But this runs, *politically*, contrary to many CSP advocates who believe that CSP can handle “virtually” all generation. You see the problem.

There is a sodium-molten salt storage system in California. There was also a nasty, dirty fire caused by this. But, assuming they get it worked out, the idea of a limited-peak lowers the cost.

Just keep in mind: for all the heat storage used, it’s an overall hit on MW output during the peak solar period of the day. So, for every hour you store heat, you take away an hour of producing power.

Thus, a 5 hour CSP plant that produces 100MW, for this period, you knock off, say, 2 hours then you are not producing for that period of time, saving it for later. You get into a cost-factor, and a pretty big one, when doing this. It has to be done, obviously.

Pump storage has limited capacity potential if there is not hydro to retrofit.



Barry Brook – “To paraphrase Burke, with apologies:
“All it will take for climate change to create havoc, wreck our civilisation, and condemn a large fraction of species to extinction, is for good men to block real solutions like nuclear power.””

And with apologies to both of you this is also true:

“All it will take for nuclear war to create havoc, wreck our civilisation, and condemn a large fraction of species to extinction, is for good men to support dangerous solutions like nuclear power and think that the ends justifies the means.”

nuff said I think.


Ender – I think you have forgotten that IFR technology would not create toxic nuclear stores or provide ready access to weapons grade material. You must also realise that many countries already use nuclear power and have nuclear bombs and have not moved to use them in anger.
I think you overestimate the possibility of a nuclear holocaust. When I was growing up in the 60’s we were all afraid of the “bomb”- but the “Cuba crisis” caused a shift in thinking. The principle of MAD (mutually assured destruction) seems to really concentrate the mind of would be bombers – as that goes for countries I am sure it would translate to terrorist groups like Al Queda. It is one thing to send young, idealistic men and women to their deaths as soldiers or suicide bombers and quite another to put yourself in danger. The Mullahs, like the Generals of WW1, would be sure to modify their responses (over the Top with bayonets; strap a bomb to yourself or fly a plane into a building)if the repercussions meant they too would be killed.
It is far more likely that the horrendous effects of climate change will kill off the human race and nearly all other species, than a nuclear war. Therefore, the end does justify the means – the end really will be the end of a habitable planet.


I haven’t had a look at Myles Allen’s paper in detail yet, but aspects of that analysis have been around. Garnaut made some use of the total budget concept. Stuff we did for the 1994 IPCC radiative forcing report captures this. Approximately, for any target CO2, there is a budget
limit and after that, all you can release is a slower (and very slowly reducing) trickle that matches how fast the deep oceans can take up the carbon. Some relevant plots for 450, 550 etc targets are in CSIRO Atmospheric Research Tech paper 31 (ed. Enting, Wigley and Heimann — available on-line from CSIRO Marine and Atmospheric Research website). see figs E.14a, E.15a E.16a, 8.6a.
However, lumping the other gases into the budget doesn’t really work. You can stabilise
most non-CO2 gases by just holding emissions constant at the value given by target concentration divided by lifetime — it is only for CO2 that the budget limit applies.


“it is only for CO2 that the budget limit applies.”

Because of the 10% or so of CO2 that remains in the active carbon cycle essentially ‘forever’ (100,000 years or so), I presume — until, as you say, it’s taken up in the deep ocean and eventually converted into carbonates.


Ocean uptake(equilibrium) is in the hundreds of years(but only absorbs 50%), with slower reaction with deep ocean carbonates( thousands of years) and eventually weathering of minerals( 10,000 ‘s).


Similar points to the Nature papers are made here:

But they also make the point that nobody is going to leave the oil in the
ground because it is just too convenient an energy source. So you might as
well just assume that it will ALL get used and only focus on how much
“room” is left for coal/gas emissions.

There is no reason to believe methane emissions will be “held constant” given
the constant denial by the meat industry of their role in atmospheric methane
levels and the gullibility and scientific ignorance of Governments who fall
for the misleadingly irrelevant “cattle are part of the carbon cycle” argument.
There are now more factory farms and feedlots in the developing world than the
developed world and while the developed world pushes a high meat diet, the growth
in livestock in the developing world will continue — requiring more water,
fertiliser, land and deforestation. The stability of methane post 1996 seems
to have come to an end and was always regarded as a mystery anyway. There is
so much slop in methane inventories that the various explanations for methanes
faux plateau always looked unconvincing (to me).


I think C & C is a good idea but I have always thought its a hard sell. Aubrey Meyer deserves a lot of thanks not just for originating the idea but for pushing C &C plus the fights he has had to endure with economists who haven’t understood it.

However, my point is if C &C is taken up or some other method internationally then Australia faces a problem. Our coal exports will go down and because the Rudd government is planning to pony up such huge amounts of welfare payments to the coal generators so they can ‘prepare’ for the introduction of an ETS this is a huge structural support for the coal industry which will just make it harder to let the industry die even if benefits of energy efficiency and IFR etc become apparent quite early. An analogy is those self righteous articles the Australian and UK tabloids run about 2nd and 3rd generation welfare receipents not being able to do anything else but sign on. Could our coal industry leaders very soon become unable to do anything else but ‘sign on’, albeit for billions of your and mine tax money.

The other week here in the UK I was at a conference and was talking to a European CC&S specialist who told me that he believed CC&S in Australia was just to support the coal export industry – which I’m sure everyone reading this agrees with or understands, but if my conversation is any indicator then this a view commonly held elsewhere. Another thing this guy said to me astounded me. I asked him how much of the power output of a coal generator CC&S operations would use up. His reply was, “20%”!!! During my masters course in Melbourne I had asked this question of a well known Australian industrial scientists who was talking to us about CC&S. His off hand reply was, “oh, only about 4%”. I would be interested if anyone on this blog has a good source of info on power use by CC&S.

Finally, I was watching the down load of Q&A of a few weeks ago with Peter Garret and Barnaby Joyce (right beside him). Joyce was getting very exercised (and doing a fine impression of a darting puffer fish in the process) about the threat to coal jobs by reductions in emissions. I think his response shows that replacements to coal, whatever their format continue to have an uphill battle in Australia and the attitudes such as that displayed by Joyce is why I think in 20 years time we may be left as a quite a poor country.


Here’s one estimate of 50% power penalty

If C&C means a global per capita CO2 allowance that could mean Australia is obliged to help out coal deprived countries with exports, sort of like a free kick in football.

I’ve heard it said that of China’s 1.3 bn people only the 0.3 enjoy middle class privileges. Using very round figures that takes their middle class emissions from 5t to 20t a head, not that much less than Australia’s all middle class 25t.



That 50% all up figure is quite something if its anywhere near correct but I would need something more than the beeb’s website.

Thats an interesting comment that C&C might mean Australia being obliged to send coal to deprived countries. I’m not sure I understand why that might be.

I remember a class mate doing a calculation of how much longer brown coal might actually last in Australia. This arose because he heard the previous Aust energy mining minister, Mcfarlane, say that there was 500 years sitting under the topsoil of the La Trobe valley but my mate reckoned that Mcfarlane hadn’t included growth in use on that and so did the figures using a compounded 2 or 2.3% per year for growth in coal use (can’t remember). He came out with 80 years left. Then he added 4% for CC&S and came out with 60 years left. Now I don’t know how accurate that is (someone may be in a good position to check) but it highlights that if CC&S gets going we may have to rejig supply lines (more trains running through the Hunter Valley) and we may come up against this peak coal that was being talked about last year.

Perhaps CC&S is only going to be a dead end.


John Morgan,(replying to #5),
One of the arguments MacKay uses is separation from villages because of noise, if you look at the UK wind map most high wind sites(>9.5m/sec at25m) are in remote regions of low population density(for the UK); Northern Scotland, Lewis, Orkney’s, Shetland’s.

The 80 GW average needed to replace all FF in UK by electricity could be generated from <2% of UK IF the high wind locations were used.This is because at 100m hub height the average wind would be 12m/sec( not his average 6m/sec at 10m,)
giving 12^3/6^3 ie X 8 as much energy. Energy lost outside the 5-25m/sec operating range is only about 2%. Most energy would be generated at about 10-18m/sec for a 12m/sec average location.This is assuming only 1.5% of the wind energy in the lowest 200m of airflow is captured( due to spacing requirements), but could be higher where only ridge lines are used.

MacKay was saying plan G would need 120 times what is installed in the UK, but now with 3.4GW installed and 2.8 GW under construction(May2009) giving about 2GWaverage, would only need 40 times this amount, and if future turbines are located at best sites due to new transmission lines would only need X10 as many turbines as now built or under construction. Thus plan G seems a lot more possible.


OK, that seems a reasonable response, assuming intermittency doesn’t cause problems. Have you put this to MacKay through his website?


I put your point about the factor x8 from taller turbines to MacKay. If he responds I’ll post it here.


re Ender (12th May): “All it will take for nuclear war to create havoc, wreck our civilisation, and condemn a large fraction of our species to extinction, is for good men to support dangerous solutions like nuclear power and think that the ends justifies the means.”

The premise is based upon two , in my view, false assumptions. 1) The supposition that an expansion of civil nuclear power generation will change the probability of an outbreak of nuclear war from very low to probable. 2) That the consequences of such a war would be significantly more damaging to human civilisation and other species than other likely or possible scenarios.

I would suggest that, as human populations continue to grow as we pass peak oil, the likelihood of serious conflict will greatly increase unless we produce adequate alternative energy resources. Should these come from coal/tar sands, we will only be delaying while actually exacerbating the problem. (As an aside, I worry that, should we achieve a soft landing for the “in the pipeline” population increase, there will be a danger that it will continue to increase beyond 9.5 billion rather than declining to something more sustainable.)

I would like to ask other correspondents more au fait with the subject than I about the likely long term consequences of nuclear conflict. Suppose, for example, that India or the USA were to have an all out nuclear exchange with China. What would be the likely effects on climate and atmospheric CO2, for example, in the short and long term? I rather doubt that that many species would actually be wiped out. Undoubtedly, human population numbers would be arbitrarily trimmed to (possibly) sustainable levels. There would clearly be immense suffering among those not instantly obliterated but that will happen in any event (in one way or another) if there is no energy solution. As a thought experiment, therefore, is anyone prepared to discuss whether nuclear conflict might prove to be a solution to the climate change problem facing humanity if other solutions fail?


Thats a bridge too far for me Douglas, but a related question is fair game, namely, of the evils of nuclear holocaust or climate holocaust, which is the lesser, and would a nuclear rollout change the balance of risk that already exists? I feel decidedly uncomfortable about this discussion, but here goes. Take it with a pinch of salt ..

On the first question, the nature of a nuclear disaster, while devastating, seems substantially localized. The earth’s ecology remains substantially undisturbed aside from the immediate targets. A large human cost is incurred, but thats axiomatic in a war. The climate can still sustain agriculture, and the earths natural heritage is intact.

On the other hand, a climate disaster is pervasive. All complex ecosystems everywhere are vulnerable and most will be lost, agriculture is sabotaged, the worlds remaining wild places are devastated, whole populations are driven to starve, thirst or fight, ocean acidification deals the marine food chain a killer blow at is base, etc. etc. And thats the low end of the warming scale.

I spent my teenage years involved with the battle for the NSW rainforests. The success of that campaign was a great victory for the environment. But I now feel increasingly hollow about it, like we were fighting the wrong battle. Whats the point of gazetting a rainforest as National Park? You can stop the chainsaws at the fence, but not the atmosphere.

I spent those same years wondering if we’d avoid a nuclear conflict. Again, it didn’t occur to me there might be something worse. And when I look at the potential climate impacts, I find myself asking, just how bad could a nuclear war be, really?

MattB, in another thread, described becoming a pro-nuclear green as like “The Crying Game” (and my weetbix went through my nose when I read that :). But for me, its Doctor Strangelove .


Douglas Wise – “As a thought experiment, therefore, is anyone prepared to discuss whether nuclear conflict might prove to be a solution to the climate change problem facing humanity if other solutions fail?”

Your joking right – you forgot the smiley on the end. At least I hope you are joking……


Perps – “Ender – I think you have forgotten that IFR technology would not create toxic nuclear stores or provide ready access to weapons grade material. You must also realise that many countries already use nuclear power and have nuclear bombs and have not moved to use them in anger.”

I haven’t forgotton it at all. The IFR has many stages of fuel reprocessing where material could be siphoned off however as the exact electrochemical process has yet to be proven on a large scale we do not really know yet.

The fact that ‘illegal’ nuclear weapons exist or have existed is proof positive that the NPT does not work and any country that wants nuclear weapons will get them anyway they can. With thousands and thousands of IFRs all over the world what do you think the chances are of any statutory body inspecting all of them sufficiently well to catch all instances of tampering with the reprocessing process?

Even then the IFR enthusiasts themselves say that IFRs are only for politically reliable countries whatever that means. Pity if Iran becomes the head country of the new UN nuclear body and decides the US is politically unreliable:-)
“The fairness issue: Will less developed, less stable countries be allowed to build IFRs with recycle? The simple answer should be No. If the U.S., China, Japan, Russia, and a few other developed countries join France in getting the bulk of our electricity from nuclear power, and undertake a massive electrification program to displace petroleum use, there will be ample conventional fuels for developing countries.”

I guess if it was completely safe anybody could have it – pity there is not a technology that is completely safe and anybody in the world can have it unconditionally with no safeguards … No wait there is – renewables.

The other little secret IFR people do not want to emphasise is that the spent fuel from IFRs is 70%-80% PU-239. Weapons grade plutonium is usually 93% PU-239 and fuel from PWRs is generally 60% PU-239.
“In outline, like this: Designers of military weapons demand plutonium that is at least 94% Pu-239, although it is technically possible, with difficulty, to make an explosive with plutonium of almost any isotopic composition. Plutonium from LWR spent fuel runs around 60% or less Pu-239, while that from IFRs tends to be in the 70-80% range, and thus is somewhat closer to what weapons designers want.”

The ‘I’ in IFR comes from the fact that the fuel processing ‘can’ occur on site however in practice my guess is that rather than building an expensive electrochemical plant on every IFR site multiple sites will have a single central reprocessing facility. If that facility is ‘conveniently’ located near a PUREX site that has been modified with the same technology used to reprocess the IFR fuel then we have a whole different ball game. A small amount of separating will take 80% PU-239 to the required 93% despite the smaller difference in isotopic mass between PU-239 and PU-240.

If you read this:

Click to access 43534.pdf

I don’t think we can really make conclusions about the proliferation resistance of the IFR until someone actually demonstrates the working fuel reprocessing cycle and/or we have a working IFR.


Wow, this is so packed with misinformation that it rivals any of your previous posts. A few examples:

Even then the IFR enthusiasts themselves say that IFRs are only for politically reliable countries whatever that means. Pity if Iran becomes the head country of the new UN nuclear body and decides the US is politically unreliable

What a stupid and disingenuous statement. And since international oversight is the topic of multiple chapters in P4TP, which I presume you still haven’t read, you’ve broken a promise by commenting on this.

No wait there is – renewables.

Yes, and potentially a greater cause of war and misery than nuclear power if it fails to satisfy the world’s need for reliable energy and water.

the spent fuel from IFRs is 70%-80% PU-239

Except that IFRs will not produce ‘spent fuel’, since all the U, Pu and minor actinides will be recycled on site to continue to produce power until they are all consumed. The only output from IFRs will be fission products, other than some trace actinides. You misread Stanford (I’m not sure if it was deliberate or out of ignorance) — he was talking about the Pu in LWR spent fuel OR Pu produced from a breeder blanket in a fast reactor — which would then required highly specialised off-site facilities to reprocess. So it’s not some ‘dirty little secret’ and to say so shows just how deceptive or ignorant you are on this matter.

however in practice my guess

Forgive me — I put no credence whatsoever in the value of your guesses (which, on the basis one what you said, above is ludicrous and unfounded speculation) on how fourth generation nuclear power might develop, and I seriously doubt that most other readers of this blog would either.


Barry Brook – “Wow, this is so packed with misinformation that it rivals any of your previous posts. A few examples:”

Thank you Barry. I was commenting on the IFR Q@A and other comments in other threads not the book which as you have said I have still not read – must check the library to see if they have it yet.

“Except that IFRs will not produce ’spent fuel’, since all the U, Pu and minor actinides will be recycled on site to continue to produce power until they are all consumed.”

I am sorry I must have done a typo like yours a few threads ago – what I meant to say was fuel that is recycled in the electrochemical process and/or a breeding blanket. Which mind you still has not been done in any large scale.

I will ignore the rest of your reply as I am trying to return to politeness.


The electrochemical process cannot separate Pu from the other actinides, whether you have a breeding blanket or not, making it impossible to derive weapons-usable fissile material using this method.


Barry Brook – “The electrochemical process cannot separate Pu from the other actinides”

I do acknowledge that the concept of the IFR is very proliferation resistant. The problem in my opinion is that it is capable of being changed and/or material is able to siphoned off into other processes like PUREX that can. I also acknowledge that the change would not be easy as the material is highly radioactive however it is not impossible. Additionally we cannot make a proper assessment of its proliferation resistance until such time the whole process is demonstrated from end to end as the paper I referenced noted. Right now we are talking theory only.

However given the level of technology you would have to transfer to facilitate the fuel making process and the thousands of IFRs that you would need, monitoring these facilities to make sure the fuel processing is carried exactly to the rules and accounting for all material would be a huge task. Again not impossible but very difficult.

That is where my concerns are and why I support a GEN IV technology like the LFTR. The LFTR is also capable of producing weapons grade material however in my future view the LFTR has only a very minor role to dispose of present nuclear waste. It would be restricted to a relatively easily monitored hundreds of sites rather than thousands.


If the IFR (and/or LFTR) was a country’s only form of nuclear power, then detecting covert enrichment (e.g. via PUREX) would be simple. Why? Because ANY form of enrichment facility would point to weapons development, since the IFR will not require enrichment, and the initial enriched loadings can come from nuclear club countries (initially) and other IFR plants set to breed for about 7 years (subsequently).


Barry Brook – “If the IFR (and/or LFTR) was a country’s only form of nuclear power, then detecting covert enrichment (e.g. via PUREX) would be simple.”

Again you are correct however did we detect Israel enriching weapons grade material?

While it is extremely difficult to conceal it is not impossible. With any very large increase in nuclear power the risk of such activities being lost in the noise of normal nuclear activity becomes greater.

Again my concerns go to the size of the nuclear energy system you want to create and the amount of oversight that will be necessary.

However I accept that it will be difficult and your explanations make sense.


If I may, you couldn’t say absolutely that the IFR is proliferation proof, but it is so hard to divert its fuel cycle, the fissile material in the IFR fuel cycle is such poor bomb material, and there are easier ways to acquire better material, that the risk is virtually nil.

There’s been much discussion on this site on this question. Ondrejch put it well:

Concerning proliferation, given the fact that IFR fuel cycle does not separate Pu, and the Pu isotopic mixture is unusable for a practical weapon design, the proliferation risk of IFR is zero.

It would take more effort to just separate pure Pu from the IFR fuel mix, than to make a simple well known graphite pile with natural uranium, and after low burn-up obtain a superior weapon grade Pu. Decades old and known technology needed, low radioactivity involved, proved and available (declassified) warhead designs, no major R&D issues.

Even after much more involved (due to intense radioactivity) separation of Pu from the IFR fuel, one would end up with vastly inferior material, which even if it could perhaps theoretically explode, practical problems such as the need for heavily shielded robotic manufacturing and machining of the warhead, problems with heat dissipation of the RG-Pu fuel nearby explosives, radiation damage to warhead electronics, and ease of weapon detection through intense radiation signature, present significant obstacles.

In the same thread, on the prospect of clandestine diversion, G. R. L. Cowan writes:

.. a CANDU fuel bundle, ten years after its retirement, can give a lethal radiation dose from 1 metre’s distance in 12 hours ..

Adding in the estimated ten times greater burnup and we get the ashes in IFR fuel, just before they are removed from it, making it ~20000 times more radioactive than the ashes in CANDU fuel after ten years.

In terms of foiling a theft attempt, this 20000 is bound to be a slight underestimate, because the radiation from fast-decaying isotopes is more penetrating, less likely to be absorbed within the fuel itself. So dividing the 12 hours by 20000 gives us a conservative estimate of how quick the supposed thief, having neglected to bring a 50-tonne self-propelled shielding flask, will decide to sit down for a little rest, and never get up again: two seconds. Whoa, I hadn’t known it was that quick.”

Turning IFR fuel into a bomb would require nation state capability in handling and reprocessing. The only entities that have that capability already either have the bomb or could build one by easier routes.


Apologies for the garbled xhtml – text in quotes is cited, outside quotes is mine, -j.

[Ed: Fixed it up for you]


Hah, that’s a bit like asking if you can ‘prove’ that CO2 causes climate change. :) I’ll go as far as to say that IFR is extremely proliferation resistant.


“Hah, that’s a bit like asking if you can ‘prove’ that CO2 causes climate change. :) I’ll go as far as to say that IFR is extremely proliferation resistant.”

Except that:
1) we have quanified the probabilty that CO2 causes climate change;

2)The climate is avlibale and open to everyone to observe (unlike some activites that humans wish to keep hidden);

3)The precuationary principle should be considered to some extent in cases of uncertainty.


Thanks John,

That’s a helpful discription.

Is there a way to use the the IFR to produce proliferateion material by means of by-passing the regular (desinged) fuel process stream .

I.e. bring in some uncontaminated uranium etc to make plutonium.


You can certainly breed plutonium in an IFR – thats what its designed to do! The trick is separating isotopically enriched Pu from the uranium and other actinides. That can’t be achieved with anything in the IFR fuel cycle. You need PUREX or some similar process. And if you already have a PUREX plant you’re making bombs anyway and an IFR doesn’t add to your capability. And if you’re not making bombs, an IFR won’t help you.

The IFR (or LFTR, etc.) allows dismantling all reprocessing facilities. With that done, civilian nuclear power is pretty much decoupled from weapons development.

I just came across an interesting paper on pyroprocessing by Hannum, Marsh and Stanford which discusses the proliferation aspects. I also found a nice graphic of the pyroprocessing modules in an IFR which might help. There’s nothing there doing any isotopic separation.

That paper comes from Gerald Marsh’s website – lots more good stuff there on fuel processing and proliferation – I think I’ve found my bedtime reading. And check out his physics section to see what a hairy chested physicist this guy is.


You also would need to run the reactor on short cycles to avoid accumulation of 240-Pu — another ‘giveaway’.

John, nice find on that Hannum et al 2004 paper. I’d read their Sci Amer version, but this one is far more detailed on some aspects, which is really useful.


Thanks John,

Its good to know that IFR is not worse than regular PUREX. I gather that IFR might make proliferation harder than most existing nuclear facilities.

But I actually meant can you use uranium without the actinides? Just plain unspiked uranium? Can you use this to get around IFRs regular intended radioactive protection and make usable Plutonium?

If proliferation were possible, it wouldn’t necessarily mean limiting IFR to countries with existing reactors (like Australia), but would be useful to consider (and plan for) how wide spread it might go. I.e how distributed would Hans Blix allow IFR to go?

Good graphic, taah!


Mark, when you split 235-U in an IFR’s initial loading, and use its spare neutrons to breed 239-Pu from 238-U, you inevitably don’t fission all of the Pu. Thus, over time, the minor actinides (Am, Cm and some Np) are created. In later cycles, when Pu is your main charge, same deal of course. You simply can’t operate a 235-U reactor without creating them (heck, even Thorium reactors which breed 233-U create some — though far fewer than an 235-U reactor).


Barry, One more differeence between the climate and IFR is we can run experiements on IFR without risking the planet.

E.g. If proliferation became a barrier to public acceptance of IFR, concerned scientist could be invited to the existing IFR and challenged to make plutoium or weapons material.


Of course non of this should be used to slow the development of IFR in nuclear club countires. (Who produce most of the CO2)


Barry forgive my reply being out of sequence, but my browser makes if difficult to read text squeeded so far over in a thin colunm.
Thanks Barry,
Sounds a tricky path, I gather this is part of the reason that IFR is not considered a higher risk than other reactors.

I assume the regular intended use of spiked fuel means that the minor actinides created (in the process you describe above) provide possibly a lower level of proliferation protection?

Is there feasible way or realistic risk that the these minor actinides might be worked around or produced in less quantity in order to produce a usable weapon?

[Again the answer to this question should not necessarily slow deployment of IFT in countries with existing reactors.]

Finally, (A slight diversion), Can the radioactive gases in Gen III reactors be captured and prevent atmospheric venting (as described for IFR by Blees).


Hi Mark,

I’m not sure I clearly understand your question. If you’re asking, can you get bomb material out of an IFR, the answer is no, not without a dedicated IFR-to-warhead factory, ie. a PUREX plant (to chemically separate the U and Pu) as well as an enrichment facility, to isotopically enrich your U or Pu. In the Hannum et al. paper I reference above, they write:

Possession of a plant for isotopic separation, centrifuge or otherwise, would be ipso facto evidence of intention to proliferate.

If you load with pure uranium, depleted, natural or enriched, you will breed plutonium, both Pu-239 and Pu-240, as well as an amount of higher transuranics (actinides). If you load with some mixture of uranium, plutonium, and other actinides, same thing.

If you want to make a weapon you’d load with uranium and short cycle the reactor, as Barry says, to avoid buildup of the higher atomic weight products. The product would include U-235, U-238, Pu-239, Pu-240, and higher actinides in decreasing proportion. The proportions of heavier nuclei depend on how long you’ve cooked your rod. And while brief neutron irradiation will give you a favourable Pu-239/Pu-240 ratio, there’s a much lower total Pu concentration, which means to get a decent yield, you’re going to have to run your reactor in serious breeding mode. Not ideal for power, and hard to hide, since you’ll be refueling like crazy.

This mixture is not weaponizable. You first need to chemically extract the U and Pu (a PUREX operation). The U or Pu you wind up with is likewise not weaponizable. For that you need an enrichment facility for either U or Pu, depending on the flavour of bomb you want. If you’re using fast reactor product, it will be plutonium flavoured.

Weapons grade plutonium contains at least 93% Pu-239. Reactor grade plutonium less than 82%. So you need enrichment.

Its been suggested that reactor grade Pu could be used in a bomb (Carson 1990). This paper was convincingly critiqued by Marsh and Stanford (Bombs, Reprocessing, and Reactor Grade Plutonium). The Carson paper, despite its shortcomings, does include a good list of the practical difficulties a would be bomb maker would face. They’re both worth reading.

So, to make your bomb from an IFR, you want to run short fuel load cycles (presumably easily detected). You need to divert the underdone rods. You then need to separate the Pu in a PUREX plant, which you’ve somehow built in secret. You then need to take that Pu and enrich it in another secret facility. Don’t get me started on how hard that is. Having recovered your Pu-239 you can then start your weapons programme.

If you have that capability, I think you’d be better off just starting with natural uranium. Its easier to get hold of, and you don’t have to do that jiggery pokery with the reactor. Also, I think a U-235 bomb is probably easier for a first time bomb maker due to less of a problem with preignition, leading to a fizzle.

Marsh and Stanford write:

The terrorist threat from reactor-grade plutonium has been greatly exaggerated by the argument that what is theoretically possible to do, can be done by subnational groups.

I think this is a really important point to bear in mind in any discussion of what it might be possible to do with the reactor fuel cycle.

One question that strikes me is whether it is possible to withdraw and replace fuel rods in an IFR core without shutting the reactor down. It would certainly be possible to design the reactor that way, and would make refueling very detectable. But you presumably need some backup generation capacity during refueling. Where does that backup come from? Alternatively, if you can do live refueling, I suppose it would be easier to do brief irradiation of rods sequentially, although it would take a long time to cook enough Pu.

So a simple question – can an IFR refuel without powering down? If not, do we need backup?


Dear Ender and Barry,

Thank you for raising and discussing some of the divisive issues on the role of IFR in the reduction of carbon in the next forty years.

I too read the comment at the skirsch site and raised both eyebrows. I also read the material in the chapters in P4TP and thought Yes, but. The buts relate to the fact that we have had sixty years of experience of international co-operation in controlling the spread of non-civilian uses of nuclear. It did some good, but maybe not enough. Perhaps we should just accept the skirsch solution and set up an exclusive consortium of the IFR countries – even though it dents the image of IFR as the universal energy problem solver.

Ender is correct to say that renewables are completely safe and no one feels stress in making the technology of renewables available to all. Barry is right to assert that there may be consequences if renewables fail to satisfy the world’s need for reliable energy and water. But I am not sure what the consequences are and what the needs are.

I went and read the MacFarlane and Stanford papers that Ender refers to and will try to digest them. The big issue is the proliferation issue – and my immediate reaction is that MacFarlane deals with it very explicitly. I am not sure that Stanford settled the issue. I will have to go back and re-digest that material.

Proliferation and its consequences still worry me.

The reasons for the closure of the US Argonne Labs program are still not clear to me. Proliferation fears were part of the issue. I don’t know what other reasons there were.

My understanding is that the Japanese, French and Russians have all had programs going since the Argonne closure; the Russian program is ongoing. There is supposedly ready to go technology available in the USA but it has never been sold. China, as far as I know, has no live program in this area. The IPCC talks of IFRs in 2030.

I think it will be a political and technical challenge to have the IFR system operational before 2030. I am reasonably sure that renewables can go some way to reducing our carbon outputs by 2030.

Kind regards,

David Murray


Thanks Barry for sorting out the technical stuff. Ender – what is your answer to my comments re MAD and the idea that CC may prove worse for mankind than even a nuclear conflict (most unlikely). Others have made the same points I see.


Mutually Assured Destruction [MAD] from the ‘cold war’ compares with the present situation with worsening rates of climate change which is MAS [Mutually Assisted Suicide] in this sense: –

in MAD fingers were poised over *but not acutally pushing* the nuclear ‘buttons’;
in MAS feet are flat on the the fossil fuel ‘pedals’;

in MAD the threat was, I’ll press the button if I think you’re going to;
in MAS the reality is, I won’t lift my foot off the pedal unless you will;

In this sense at least, MAS is much worse than MAD.


Perps – “Ender – what is your answer to my comments re MAD and the idea that CC may prove worse for mankind than even a nuclear conflict (most unlikely).”

Sorry Perps I am not prepared to discuss what is worse. The answer is that they are both too horrible to contemplate and action must be taken to ensure that both do not happen.

My opinion is that climate change can be largely held to 2 deg by using renewables along with some changes to the way the Western world does things.

MAD and MAS can be avoided by ridding the world of the spectre of nuclear weapons that has been hanging over us. While it is absolutely true that the vast majority of countries do nothing more than use their nuclear programs safely for electricity alone there are the nations that have built illegal weapons. To my mind trusting politians with that much power is not safe. Given a threat to a nation nuclear weapons are seen as the ultimate deterrent to attack. It is instructive to notice that the nations that have built illegal nuclear weapons have perceived threats or want something from the international community.

Again it is my opinion we stand much more chance of ridding the world of nuclear arms if uranium nuclear power becomes a forgotten technology of our ignorant youth, by not relying on it now. It is a vain hope I know however it may just work.

My again vain hope is that we can learn to live within natures flows rather than natures stores.


I applaud and share your hope, but am pragmatic enough to realise that nuclear disarmament is not going to happen any time soon, if ever!
I still maintain, however, that the threat of losing their own life acts as a great deterrent to any country’s leader contemplating pressing the button. I don’t believe more nuclear power will make any difference to that scenario.


Dear Barry,

Your discussion of the Nature paper and the implications for Australia’s renewables target was welcome. Facing up to the implications of the required target is needed.

Going straight to the bottom line I think your conclusion (1) is correct. I don’t think anyone would disagree with it unless they thought renewables to be hopeless and energy savings a myth.

(3) I personally think that the evidence is now sufficient to be able to say with a fair degree of certainty that electrified vehicles can reduce carbon outputs from transport (with the exception of aircraft) to zero by 2050.

(4) I don’t know about this as a central plank in the carbon reduction plan – though I can see that it can play a role in the production of syngas.

(5) Yes, deforestation has to be stopped. The soil carbon and biochar stories are still open to a lot of discussion and refinement.

(6) Livestock emissions are part of the agricultural problem. Nitrogen fertilizers and a fuel to run agricultural machinery are difficult issues.

(2) There are assumptions that (i) renewables may not be able to meet our rapidly expanding needs after 2030 and (ii) that nuclear will be able to fill the gap. There are (iii) disagreements about what is meant by our rapidly expanding needs for goods and by implication for energy. There is also (iv) discussion about public acceptance of, and future developments in, technology of renewables and nuclear is. I think this point is the one on which I find it most difficult to agree.

Fortunately disagreement on (2) does not preclude agreement on the other items – so we can proceed to work on them until the crunch day arrives and we have to decide on nuclear or renewables. I don’t think that day will arrive until 2015 at the earliest.

I think your last two sentences are too demanding. To argue that being anti-nuclear in 2009 is to be a climate wrecker is too strong. It would carry more weight if renewables were not given the tick of approval in your bottom line point (1). If renewables are a proven flop by 2015, and nuclear has proven it can do the job then to be anti-nuclear would be to be a climate wrecker. But we are not there yet.

Kind regards,

David Murray.


Perp, the point you raise (along with Aubrey) is important. MAD and MAS both mean disaster. I wouldn’t try to rate one as worse. But I would add a third, which is asymmetric warfare using a nuclear weapon . MAD is a more appropriate descriptor where two super powers face off. Asymmetric warfare is an increasing risk where many smaller parties have access to nuclear weapons. In this case it is possible the nation of the attacker remains either unknown or an inappropriate target for a nuclear response.

I’d also add a point Barry made elsewhere regarding the need to provide energy in a world with the screws of limits to growth starting to cause friction. We are actually seeing this friction already- My reading is that climate impacts are predicted to get nasty for larger populations first in Africa and Sub-continental Asia. Yet here food shortages , disease, and conflict are already bighting for large populations. This arose despite global abundance of cheap fuel.

The problem is due to structural inequality and perverse global agreements decided by rich nations and perversity of power and the profit motive. I.e. it is down to power imbalance and the economic pressure to exploit what and whoever you can.

If IFR works out , along with the (human dependant) non-proliferation agreements , a second agreement need serious consider. The agreement should act to prevent an energy apartheid that acts as a barrier to development.

“High-energy consumption has always been a prerequisite of political power. The tendency is for political power to be concentrated in an ever-smaller number of countries. Ultimately, the nation which control the largest energy resources will become dominant. If we give thought to the problem of energy resources, if we act wisely and in time to conserve what we have and prepare well for necessary future changes, we shall insure this dominant position for our own country.” (Admiral Lewis L. Strauss)

The good Admiral was thinking in cold war terms, yet today we need to consider the development of the most vulnerable.


Dear Mark

Thank you for your comments which I note. However and with respect, my point was that MAD and MAS are *not* the same. MAS is clearly worse than MAD and continuing with it is the worst of all options – in extreme, a runaway greenhouse effect.

MAD was *latent* – it COULD happen. In other words it could and it would mean disaster, if the deterrence argument broke down . . . . but [so far] it hasn’t.

MAS is *patent* – it IS happening. In others words, it is making things worse day by day and it guarantees disaster, unless things fundamentally change.

i.e. MAS is worse because its happening and worsening.

The point with C&C is that, assuming everybody actually agrees that MAS has to stop and achieving the objective of the UNFCCC is sensible as not achieving it is not, they will then need an organsing framework within the structured limits of which to internationally schedule the requirement to do ‘enough soon enough’ jointly on climate change, as severally we remain at the mercy of what you might then call unwanted MAS, or MAS by accident in other words just doing too little too late [this is the Kyoto debacles all over and largely the basis of US argument all along].

However, under the global momentum of ‘polluta continua’, the reality with climate change politics has always been the *double-jeopardy* of asymmetric growth and damages.

Two thirds of people globally have persistently enjoyed 6% of global income measured as USD, while the other one third enjoyed 94%. In each case there has been with an ghg per capita impact signature to match.

While this *expansion and divergence* [E&D] grew globally at 3%/yr since WW2, damages [uninsured losses] from climate change [Munich Re] grew at 6%/yr or at least at twice the rate. If in this condition of MAS, feet remain flat on the pedals, its only a matter of decades before the latter zeroes the former, and MAS takes out both sides of the quarrel permanently.

Separate Development is not Sustainable Development and asymetric warfare in these circumstances – dirty-nuclear or not – is a MAS [dys]function of E&D. It is worse than MAD, which, as you say was symmetric, but as I repeat to you was latent not patent like MAS.

With respect to IFR and C&C. C&C is technology blind. World Nuclear Association [WNA] love C&C because it gives them a rational framework in which to articulate their solution to what they have presented as their serious concern about climate change.

My own feeling about this is, OK fine, but the key question for everyone – especially, given the contraversy, including WNA – is what level of demand do you expect to service?

Infinite demand there may be, infinite supply there is not. Being messy about this in conditions of worsening MAS doesn’t leave much room or time to repent the mess at leisure.

As Ross Garnuat recognized, climate change is a diabolical problem to which humanity may well lose . . . . i.e. like it or, failure is an option . . .

Once again I offer a link to evidence to the UK House of Commons Environmental Audit Committee enquiry into the UK Climate Act. It asks where did the figures come from and where the models on which they were based valid? –


Aubrey – I wish I had said it as convincingly and coherently as you have! Thakyou for saving me the effort:)


Dear Aubrey, This is an excellent and I beleive accurate presentation of the role out of MAS. I agree more or less with every word. I think we both agree that the sesitivity of climate system may have some range of doubt, but the risk range from extreme to very bad (if we consider the real global human impact).

I would add another point, which is in human thinking CC is happening in slow motion. We can see it and predict its trajetorty.

Human conflict can have short ignition times. And the tools of destruction can gather in secret. And in studying conflict, we are not measuring universal physical properties, hence the probabilities are harder to estimate.

We know the riks of CC are grave, yet the probabiltiy of a nuclear conflict are not as predictable, and this does not mean the probability is low. It more on an unknown probability with extreme consequence.


Here is a C&C-scenario image with: –

[1] numbers for fossil fuels only
[2] for all-regions/all-years 2000-2050,
[3] contracting globally to near-zero by 2050 and
[4] converging to equal per capita globally by 2020 [it’ll be there for 28 days only]

Use Acrobat ‘tools’ ’select and zoom’ then ‘pan and zoom’ to get big-picture and detailed numbers as-above simultaneously . . .

C&C can be shown this way at any rates specified.

It is my impression that something like this is now the next step.


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