SNE 2060 – are uranium resources sufficient?

In the previous SNE2060 post, I considered four possible scenarios for expansion of ‘Generation III’ thermal nuclear power reactors for the period 2010 to 2060. I attached no probability to them, but obviously not all are equally plausible. For instance, I strongly doubt that the TR2 scenario, which followed the WNA high scenario to 2030 (of 1,350 GW) and then continued this onwards to a massive 10,000 GW of installed worldwide nuclear capacity by 2060, will come to pass – at least not using only current-generation thermal reactor technology based on an open fuel cycle. Indeed, the scenario I think to be most likely is TR1, because it fits logically with a synergistic expansion of closed-fuel cycle ‘Generation IV’ technology like the Integral Fast Reactor and/or Liquid Fluoride Thorium Reactor.

I will explore some of those complementary multi-tech pathways (i.e., the Gen III/IV mix) in later SNE2060 modelling. But first (in the next three SNE2060 posts), I want to examine some of the key assumptions and outputs of the open-fuel-cycle ‘Generation III’-only route, with a critical eye. These include: (i) uranium resources (this post); (ii) spent nuclear fuel storage requirements, and (iii) implied build rates of reactors.

Here I’ll consider uranium (U) supply under a situation of no used-fuel recycling (i.e. once-through). (Reprocessing light water reactor fuel rods to create MOX [mixed-oxide fuel] still amounts to using the uranium resource inefficiently, increasing the energy yield from from 0.7 to just over 1 per cent. It is also expensive and does not noticeably help in decreasing the radioactive life of the waste.) I should note also that I’m hardly the first person to blog about uranium resources (e.g. read here and here, as well as the comprehensive assessment given by the WNA here). But I’ll give my own spin on it anyway, so as to keep the SNE 2060 series more-or-less self contained.

The world’s reserves of uranium are currently estimated at 4.5 million tonnes (t) extractable at less than $US80 a kilogram (incidentally, the market spot price for U on 14 Oct 2010 was $US 106/kg). By ‘reserves’ I actually mean ‘reasonably assured resources‘ (RAR, which is typically defined as the mineral resource that occurs in known deposits of delineated size, grade and configuration such that the quantities could be recovered within the given production cost ranges with currently proven mining and processing technology) plus inferred resources (based on direct geological evidence and extensions of well-explored deposits). World production was 50,722 tonnes in 2009, and has grown at an average rate of 7.1% over the last 3 years. World demand from thermal reactors is greater than this mined figure, at about 70,000 t/a, with the difference made up relatively inexpensive secondary supplies (stockpiles, weapons etc.).

Two useful things to note here. First, look at this chart:

See how most identified U is recoverable at <$80/kg, and relatively little more at <$130/kg? This is because it’s not really worth exploring for the more difficult-to-extract stuff until the easy and cheap (and already identified) ores have played out. Once you’ve identified 20 to 30 years of assured supply, what’s the urgency, after all, in identifying decades more? The fallacy of ‘peak metals‘ fails to consider this little economic principle (this is the main reason why Julian Simon won the famous wager with Paul Ehrlich).

But that said, with the prospects of a nuclear renaissance, exploration has notched up over the least few years, as illustrated in this figure:

Note the positive correlation between exploration dollars spent and the expanding size of the identified RAR for uranium. This suggests that with more exploration, there is still a lot more (relatively cheap) uranium left to find. More on these economic geology fundamentals here. It’s difficult to speculate on how much further the RAR for uranium will rise over the next few decades, but it’s likely to be considerable (my guesstimate — quote it back to me in a decade hence — is that it will have risen to ~10 million tU recoverable at <$US 100/kg by 2020).

From a greenhouse gas emissions perspective, Lenzen (2009, pg 49-50) conservatively estimates that if ALL the RAR ore grades between 20% and 0.01% were used to generate power using once-through thermal reactors, the resultant 210,800 TWh of electricity would generate around 17 Gt CO2e, at an average emissions intensity of 80 kg CO2e/MWh. (This is working under the assumption that all the energy used for mining, enrichment etc. comes mostly from coal-fired power stations and oil-burning machines, rather than nuclear electricity and synfuels — parse the logic on that if you are so inclined). For the ore grades greater than ~0.05% U (which is still the majority of the currently identified RAR), the emissions intensity drops to <20 kg CO2e/MWh (Weisser 2008).

Beyond the immediately mineable resource, there are another ~35 million tU in lower-quality ores and mineral compounds (phosphates), which the Organisation for Economic Co-operation and Development (OECD) says could be economically extracted for a few hundred dollars a kilogram (cited in IPCC 2007 Working Group III report, chapter 4). Interestingly, we’re probably going to want to mine these phosphate ores at some point anyway for reasons other than energy, to keep the world fertiliser markets supplied. Indeed, according to a co-authored study by leading American expert John P. Holdren (now Director of Science and Technology Policy for the US) and IPCC Chair Rajendra K. Pachauri, there is ultimately likely to be between 100 and 300 million tU accessible via mining at a price of <$US 350 (in 1992 dollar terms).

Then, of course, there is the huge potential ‘stockpile’ dissolved in the oceans, which contain 4.5 billion tonnes (Gt) of uranium. Even today, we have the technology to extract uranium from seawater  (see figure on left) at a cost of between three hundred to a few thousand dollar per kilogram. If you think this is crazy, do yourself a favour and read the assessment of this possibility by Nobel Laureate Georges Charpak in his book “Megwatts and Megatons” (Pg 210-212, 220; Google Books Extract Here). Now as Mackay (quite realistically) points out, even with refined and scaled up extraction methods, we might only be able to access a tenth of this – say 500 Mt – per 1000 years, due to the slow pace of ocean circulation and the relative diffuseness of dissolved uranium in seawater.

Is this cost-effective? Well, for current light water reactor technology, the total fuelling costs – including mining, milling, enrichment and fuel-rod fabrication – is around $US20 million a gigawatt a year, for “yellow cake” (uranium oxide: U3O8) at a price of $US70 a kilogram. In unit cost terms, that works out at 0.2 cents a kilowatt hour for the uranium “fuel”. So even if uranium ore prices rose by 10 times (to $US 700/kg), it would lift the price of nuclear-powered electricity by 2 cents a kilowatt hour for Generation III tech. This is equivalent to the average household’s electricity bill rising by $150 a year in Australia (at present it is about $1,000 a year). (By comparison, a 10-fold rise in the price of coal would increase annual household electricity costs by $900, while for natural gas, such a price rise would cost $1,700 extra each year.)

Finally, I should link this back to the conclusions of SNE 2060 Thermal Reactor scenarios. The TR1 option required the consumption of about 14 million tU by 2060, and TR2 required about twice that. Clearly, both figures are higher than the current RAR for mined U, but then again, are lower than the U resource that the IPCC estimated was worth extracting from phosphate minerals, and is a tiny fraction of what is conceivably accessible in sea water at a reasonable price. I conclude, as the recent MIT 2010 report did, that uranium supplies are not a serious constraint on nuclear power deployment during the 21st century, even at very ambitious growth scenarios. HOWEVER, that does not mean that I’m arguing that TR2 is the most desirable — or indeed most likely — scenario. Far from it, as I plan to elaborate in later SNE2060 posts, when I discuss the Gen IV synergy. I just wanted to squash a few ‘mythconceptions’, that’s all.

About these ads

35 Comments

  1. Thanks for linking to my article, Barry, but you’ve linked to my piece on uranium mining techniques, whereas I suspect you meant to link to my nuclear sustainability essay, which is the next one down on my blog from the one you’ve linked to.

    [Ed: Thanks, fixed]

  2. I think even the TR2 scenario is low if the world will have 9 billion people in 2060 with an average 2 kw energy consumption. Thus conventional uranium won’t get us there and Gen IV will have to arrive well before then. By 2060 remaining fossil fuels may not have much net energy rather they will be mined for ready-made hydrocarbons, to wit the proposal for a CANDU to help dissolve Canadian tar sands.

    I wonder if future U consumption could be split into a low burn path and a high burn path. Depending how that works out there might have to be another path for ‘bred’ fuels starting possibly before 2060 if you accept TR2 is on the low side.

    As a philosophical aside notice how the finiteness of resources is now blindingly obvious with river water. I’d have to single out South Australia for being pig headed both about showpiece water usage (lower lakes and Coorong) and also blocking the single biggest contributor to increased U production, namely the Olympic Dam expansion. Er they have lots of windmills so I guess they’re cool.

  3. Barry,

    I am assuming that, in your final paragraph, you are suggesting that you would favour no more than 3000GW of once through reactor power by 2060, notwithstanding the fact that you have calculated a minimum need for 10000GW of total fission power by this date. I am not trying to preempt your next posts, only to clarify my understanding of your current stance.

  4. thanks for this article. I’ve been looking for something like it.

    on simon, it’s important to understand the grain of truth in the “you will find it if the price is right” argument.

    but I think the argument makes a lot more sense for minerals. I recall Lomborg in Skeptical Environmentlists making a similar Simonian argument against peak oil. He bet against oil ever hitting 60 dollars a barrel.

    He lost that bet.

  5. U supply was and is an artificial problem drummed up by antinuclear forces, up until then it was never a serious consideration. Anyway, if the price rises and no new supplies are found, high-burn reactors as well as thorium and other breeding cycles are still waiting in the wing, and could be brought on line swiftly enough that there would be no crises.

  6. I’m pleased to hear that supply of uranium is not a big worry however I would not be too quick to regard peak metals as a fallacy.

    On the current available evidence we live on a finite planet so it is inevitable that production rates of many heavily used minerals will decline.This will be due to the expense and difficulty of accessing remaining supplies.Everything is not possible,let alone probable.

    Reduce,Reuse,Recycle – Gen IV reactors appear to embody this principle.

  7. There are another couple of fundamental reasons why it’s a mistake to uncritically extend the concept of peak oil to peak metals. One is to do with the geology of how they occur. There is pretty much a continuum of metal concentrations in the crust, thus economic extraction can be readily moved along this curve as prices vary. Oil, on the other hand, to a first approximation is binary – it’s either there or it’s not.

    The second, ultimate reason is the law of conservation of matter.

  8. I should have added a third, to do with the first – the fact that because it’s a liquid, oil is economically extractable from almost any depth in the upper crust, whereas with metals you’re again looking at a relatively gentle continuum of extraction costs with depth. The depth to which you bother exploring changes accordingly. With oil, though, when you couple with the fact that deep exploration technology (i.e. seismic) is much more effective for oil than for minerals, the ‘inferred resource’ will be much closer to the actual total global resource, with the concomitant prospect that the eventual production decline will be that much steeper.

  9. Douglas, yes, that is my expectation, given current deployment strategies and my assessment of medium- to long-term plans of various nations pursuing large-scale nuclear development today.

    greg/Podargus, there is definitely a difference here between oil vs common metals (copper, iron, zinc etc.) vs poorly-explored metals (uranium, thorium etc.), for the reasons Mark Duffett (BNC’s resident mining geologist) pointed out. I agree thoroughly with the principle of recycle and reuse, but I don’t necessarily see the need for ‘reduce’ when it comes to metal use – at least in the short- to medium-term.

  10. Excellent article Barry.

    We should plow on with the thermal reactors for the meantime, but ensure alternative methods are within arms reach, through a reasonable R&D effort.

    I found Mackays treatment of both U resources and Sea water extraction overly simplistic. The sea U extraction system is in an early stage of development, I wonder how advanced it will be in 50+ years when we actually need it.

    It pains me to say this, but what if all our favourite advanced reactor types are never required? I can imagine fusion or something even better will be developed by the time we run out of cheap ore.

    Would 20/80g co2/kwh be enough of a saving to beat global warming, Barry? Considering economic growth etc.

  11. @Huw Jones – Advanced fission reactors will be commissioned because many countries do not have local uranium resources to exploit and breeding is their only path to fuel independence. And this will be a consideration as one suspects that the politics, controls and obligations surrounding the trafficking in fissionable material will become more, not less onerous.

  12. Would 20/80g co2/kwh be enough of a saving to beat global warming, Barry? Considering economic growth etc.

    Yes, it would.

    You’ve got to think synergystically, Huw. If the world reaches 10,000 NPPs, such that they replace virtually all stationary energy AND generate synfuels etc. to replace oil, what do you think the economy-wide emissions factor is? Answer: virtually zero.

    This gets to one of the great fallacies of the Storm-Smith/Diesendorf ‘argument’ that by the time we started accessing really low-grade ores, the emissions factor on the full nuclear cycle would be almost as high as fossil fuel combustion. It will actually be the complete opposite. It just takes a little bit of thinking to reason why.

  13. Barry, DV8, I totally agree.

    I definitely think that we should have Breeders/alternative fuel options ready for roll out within 20 years, as a back up at least.

    I can definitely see your point Barry. The carbon intensity of NP is likely to drop over time rather than rise, due to the integration of the fuel cycle with NP infrastructure.

    And many thanks to both of you for commenting on my blog. I’ve been neglecting my online life due to university work the last two weeks, so haven’t been able to write any serious comments on there or get my first proper entry added.

  14. Great information. Nuclear (fission) should only be considered a stop-gap energy source or supplemental energy source to be used in conjunction with the multitude of other energy producing methods. It does behoove us to find and mine as many of the energy producing fuels as possible before we need them. I’ll be bookmarking this for reference. Keep up the good work!

  15. Barry,

    I haven’t caught up with the last two threads yet. The article on this thread was really needed. I haven’t had a chance to read it carefully yet.

    I would like to comment on your latest comment. At 16 October 2010 at 1.29 you said:

    This gets to one of the great fallacies of the Storm-Smith/Diesendorf ‘argument’ that by the time we started accessing really low-grade ores, …

    I agree with the rest of your comment but don’t really agree that we will be “accessing really low grade ore” at any time.

    I don’t believe the ore grades will change (much) over time. The average or grades we are accessing my increas or decrease over the decades and centuries ahead). We will have to go deeper (after we’ve found most of the ore bodies that have a surface expression, but exploration methods and recovery methods will improve in step. If we continue the trends of the past and project them forward the costs of mining and processing will decrease in real terms over time.

    Exploration methods are improving all the time as are mining methods. We are now mining uranium in some deposits including in South Australia by insitu leaching. That is down without a conventionsl mine by drilling holes and pumping leaching fluids through the uranium orebody. In the future we’ll have even better ways of removing the ore without conventional mining.

    I agree with your article above. We do not need to concern ourselves with shortage of uranium in the next 100 years or so and breeder reactors will be cheaper than once through reactors long before we need to worry about shortage of uranium.

  16. Nuclear (fission) should only be considered a stop-gap energy source or supplemental energy source to be used in conjunction with the multitude of other energy producing methods.

    I wonder how Leonard reached such a conclusion. Nuclear power is clearly far and away the best power source for us into the indefinate future. The only comparable sources are the limited and climatically problematic fossil fuels, and the even more limited hydro resource.

  17. Working in kt we have an assured reserve of 4,500 kt of U with present annual consumption of 70 kt including from secondary sources. Even in the no-growth scenario of 70 kt a year that reserve will run out in 4500/70 or about 64 years, circa 2070.

    With 5% annual growth I find that the 4500 kt U will be used up on a once through basis in about 27 years. That U consumption goes from 70 kt in 2010 to a grand finale of 262 kt in year 2037. Game over for cheap single use uranium. Check my calcs and any scaling errors.

    However the 5% demand growth assumption is inadequate if indeed we are close to peak coal and global peak gas is just a human generation later. Gen IV may have to be ready for mass rollout within a decade. It may be hard to see because recession has dampened energy prices and we think we have plenty of everything for now. I think it will become clearer as coal, oil and gas prices escalate (relative to GDP or in absolute terms) just in the next few years.

  18. Finrod,
    In a sense Leonard is right. Fission is a “stop-gap” on the way to Fusion, albeit a “stop-gap” that may provide mankind’s energy needs for many millenia.

    I spent some years on work relating to Fusion but got discouraged when the “Pot of Gold” kept receding further and further into the future.

    If our civilization continues on its present course, one would expect the problems of generating Fusion power on a large scale to be solved in a century or two. However, the plant required might be expensive when compared to sophisticated Fission plants.

    It would not surprise me to find Fusion power used only in situations where no other power source would be adequate. For example, inter-stellar space travel might be possible using fusion power.

  19. John Newlands writes,

    With 5% annual growth I find that the 4500 kt U will be used up on a once through basis in about 27 years. That U consumption goes from 70 kt in 2010 to a grand finale of 262 kt in year 2037. Game over for cheap single use uranium.

    What date would you have got for “Hasn’t it gone quiet all of a sudden” if you had done the calculation in 2007?

    With 35000000000 kt U in the upper parts of the continents, enough that its use as “cheap single use uranium” would suffice to put all of the continents and much of the mantle through rock crushers, it is meaningless to do such calculations without putting in some estimate of the future effectiveness of prospecting.

    Which in a way I suppose you have done: you have implicitly set that effectiveness at zero, independent of price.

    (How fire can be domesticated)

  20. John Newlands

    @ 16 October 2010 at 17.49

    Check my calcs and any scaling errors.

    Your analysis is baseded on a false premise. You are assuming that that assured reserve is 4500kT and this wont change with time. That is completely wrong. Based on the amount of uranium in the earth’s continental crust, the proportion of that that is concentrated at higher than the average, the fact that the concentration that is economic is continually reducing as mining methods improve, the fact we can explore and extract from deeper in the planet as time progresses, then I say the amount of uranium available is effectively unlimited.

  21. It doesn’t inspire any confidence that the Olympic Dam expansion has been deferred. That one mine would raise U production from a recent 4 kt to 19 kt a year. Perhaps BHP has figured they will do better financially getting $200 – $300 per kg of yellowcake some years from now rather than a short term $100.

    As I’ve said before we should couple the OD expansion with a NPP build. The project needs 700 MW presumably including desalination, perhaps more if diesel machinery is replaced with electric. The current mine totally relies on fossil fuel inputs. A gigawatt sized NPP could export surplus power to the grid. The snag might be the need for overseas enrichment.

  22. John Newlands,

    It doesn’t inspire any confidence that the Olympic Dam expansion has been deferred. That one mine would raise U production from a recent 4 kt to 19 kt a year. Perhaps BHP has figured they will do better financially getting $200 – $300 per kg of yellowcake some years from now rather than a short term $100

    The reasons why Olympic Dam has been deferred would be based on the finances. If they can make a higher return on investment with lower risk elsewhere, and employ their available funds better elsewhere, of course they will do so. At the moment their are a lot of uncertainties for investing in Australia. We have an anti-business, anti-mining, alliance, minority government between Labor and Greens. The South Australian government is not supportive of providing the port, water and power that is needed to make the project as feasible as it could be. I’d wait too and hope and expect that the situation will be better in the future. What they are doing makes a lot of sense to me. They can invest their available funds with lower risk and higher return in Canada and some African, South American and Asian countries than they can in Australia.

  23. Pingback: SNE 2060 – can we build nuclear power plants fast enough to meet the 2060 target? « BraveNewClimate

  24. Pingback: Anti-nuclear cartoon book, 1978 – anything changed? « BraveNewClimate

  25. Pingback: Till & Chang: “Plentiful energy” « PassiiviIdentiteetti

  26. At the risk of being a wet blanket. We must not confuse a world running on 100% electrical energy with the highly portable oil based energy system of today. Nuclear energy is not very portable (even with batteries). The premise that Electrical energy is the same as oil is false. Nuclear in one form or another is the only viable alternative but make no mistake. There are two caveats. It won’t be the world of today. Without oil about 5 Billion people will cease to exist. The nonsensical economics of today (Infinite growth with finite resources) will cease to exist. It will be a very localised society based around farming (ring a bell?) and essential services like making clothes. What portable energy resources there are will be available in quantities so small they will only be used for mining and recycling. eg. Bio diesel. Electrical energy will be a luxury not a necessity. That’s the first caveat. The second one is bit more depressing. There is a high probability it will never happen. As the effects of peak oil take a grip (they already are…death by a thousand cuts) the world will descend into chaos. There will no time or inclination to make the correct decisions. It takes years and huge amounts of energy and materials to build Nuclear reactors and I believe we are out of time and resources. The dying men will be clutching at the proverbial straws. So yes, of course Nuclear is the answer. Getting there in this Global idiocracy. That’s the interesting part.

  27. Much of what we use oil for we could replace with electricity (e.g. electric cars, trains are even easier, and large shipping could be nuclear powered) and we could produce all the fertiliser we need without using any natural gas (it’s hydrogen that is needed, not methane, methane just happens to be the cheapest source of hydrogen right now) while we also genetically engineer our crops to require less fertiliser.

    We should also be able to produce synthetic hydrocarbons for chemical feedstocks cheaply enough from CO₂ (biofuels might also be useful here, we don’t need anywhere near as much for feedstock as we use for transportation).

    As the climate changes air conditioners are going to become much more necessary in many places turning electricity into a necessiity for a lot more people, but nuclear can supply whatever we’ll need for a very long time so that’s not a worry.

    As for peak oil, I wish it were happening because then we’d actually have some motivation to get off fossil fuels.

  28. John:

    Sure it is true that while we can get all the electricity we need from nuclear fission even if nothing else works, running mobile machinery like cars will be more difficult as oil gets scarce & expensive. It could turn out that we don’t get batteries much better than the current best & alternatives to oil for liquid fuels are either very expensive or can’t be scaled up to anywhere near the level that we currently use petroleum.

    However, given this premise, this doesn’t mean we get no long distance transport, we get a world in which long distance transport is mostly by electric railway (possibly maglev) & nuclear ships. Air transport becomes much smaller, done only when it’s worth paying exorbitant prices. Some short distance transport can be done by battery powered vehicles, though bicycle & walking would replace a lot of car use. I suspect farm tractors, bulldozers etc. would be powered by batteries that get switched for recharged batteries after a few hours work. Doing something similar for cars would require a network of battery recharge stations larger than the current network of gasoline stations since the range of battery cars is shorter before recharge than gasoline cars before refill.

    We do get some odd looking results in sparsely populated areas. In the large land areas beyond the net of electric rail & battery recharge stations, travel would revert to muscle power: walking, horse, camel, llama, dog or reindeer sled, & canoe. Travelers in these regions could carry light weight electronic gear like satellite phones & GPS receivers, & their other gear would be made of modern light & strong materials, but they would move at pre-industrial speeds.

    While we could get some regions collapsing economically because they don’t have some cheap energy source like nuclear, hydro or geothermal, at least some parts of the world will have the sense to build nukes etc. & civilization will spread back from those areas. (Interesting setting for a science fiction story.)

  29. The IFR increases the energy output from same uranium by 2 orders of magnitude. The used fuel as waste will be correspondingly reduced over the time. Re-using the spent fuel/depleted uranium in solid or liquid fueled fast reactors will ensure sufficiency of uranium for centuries from existing mined uranium.

  30. It’s great to see BNC opened up for comment again.

    With cheap nuclear power in the future we’ll be able to make liquid fuels for transport. The US Navy has estimate the cost of making 100,000 gallons per day of jet fuel from sea water on board it’s nuclear powered aircraft carriers. It may be viable, for strategic reasons, now.

    John Morgan has estimated the cost to produce jet fuel from sea water on land http://bravenewclimate.com/2013/01/16/zero-emission-synfuel-from-seawater/. I expect it would be cheaper if the hydrogen was produced by high temperature reactors like the Chinese one instead of by electrolysis: http://www.uxc.com/smr/uxc_SMRDetail.aspx?key=HTR-PM

    I don’t foresee a shortage of energy in the future. I see no major problem we cannot address. We just need to get over the issues that are preventing us getting to nuclear electricity cheaper than from fossil fuels.

  31. Pingback: Entering Space – ultimate energy resources? | Brave New Climate

Leave a Reply (Markdown is enabled)

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s