By Ommission

Today witnessed an attempt by Helen Caldicott to offer commentary on South Australia’s nuclear fuel cycle royal commission. You can read it here but there are no prizes for guessing what it contains. Maybe for what it doesn’t contain, but we’ll get to that.

If I may correct a few highlights (Where to begin? Does she do any research at all?):

The people advocating a nuclear South Australia have no comprehension of genetics, radiation biology, oncology and medicine. Or they are willing to ignore the risks.

My own comprehension of genetics stems from my major in biochemistry, earned at the University of Adelaide, and I advocate for at least the fair consideration of nuclear in South Australia. More authoritatively, the late Professor Wigg was pivotal in bringing the benefits of radiobiology and oncology research and treatment to this state and more widely to the nation, and he also advocated for nuclear energy. He was unwilling to ignore the risks of excluding nuclear.

But more fundamentally, the point Caldicott entirely misses is that her refusal to listen to anything from nuclear professionals makes her worse than mistaken. So when she claims, “But they are wrong. Only 9 per cent of the plutonium successfully fissions, leaving 91 per cent of it with its extensive life, as well as producing deadly fission byproducts” as if she understands the physics involved, and Roger Blomquist of Argonne National Labs observes that this claim is nonsensical, her intentions must be seriously questioned.

The first argument is environmental: that nuclear power is the best way to reduce greenhouse gas emissions and as such combat climate change. But this ignores the huge expulsion of greenhouse gas that goes into producing nuclear power.

This polemic appears to hinge on the claims of Storm van Leeuwen and Smith, made on their website and not in the peer reviewed literature. But it has been criticised in the literature and thoroughly debunked. It is also inconsistent with figures presented by the US National Renewable Energy Laboratories.

Heard is advocating the reprocessing of radioactive fuel. This involves dissolving intensely radioactive fuel rods in nitric acid and chemically precipitating out plutonium, which would then fuel small, modular, fast-breeder reactors.

Why does Caldicott call me an occ. therapist when I am no longer registered, practicing or professionally developing? http://t.co/jPqo4fV1FO

— Ben Heard (@BenThinkClimate) May 30, 2015

For the same reasons, and by the same logic, she calls herself a medical doctor I suppose!!! http://t.co/jPqo4fV1FO

— Ben Heard (@BenThinkClimate) May 30, 2015

 

Aside from the fact that countries like France conduct large scale reprocessing of nuclear fuel safely (which helps them run economically on a majority of nuclear power, keeping emissions at world-leading low levels as well as supplying large annual exports to coal-dependent neighbours), what Ben, Barry and others, and now Senator Edwards have been clearly talking about is an unrelated fuel recycling method which utilises electrochemistry in a non-water, molten salt medium. No nitric acid involved here, Helen. The entire idea is that fissionable transuranic materials are not separated (keeping them useless for weapons diversion) and do not and cannot leave the site, instead being recast as alloy fuel and returned to the reactor.

Moreover, the uranium enrichment facility she cites as currently needing so much coal-fired electricity… is shut.

The dump would be constructed on Aboriginal land, near and likely above the Great Artesian Basin.

If this isn’t the most opportunistic and intentionally inflammatory sentence of the entire screed, I don’t know what is. There’s absolutely no basis for claiming a facility would need to be situated within these limits. Indeed there’s no reason for insisting on it being so far from major populations at all.

There would also be americium-241, even more deadly than plutonium…

So “deadly”, we put it in plastic casings and screw it onto our ceilings to warn us of the mundane hazards of house fires.

The BBC is more interested in the facts around plutonium than Caldicott is.

The South Australian population would be likely to experience epidemics of cancer, leukaemia, congenital anomalies and genetic diseases through future generations as the waste inevitably leaked.

You knew it was coming, didn’t you? The shameless prognostication of cancers, mutations and death. But wait – isn’t this what she predicted for Western Japan nearly 4 years ago? Come to think of it,

She hasn’t mentioned Fukushima at all!

Caldicott is given a mouthpiece to perpetuate her own peculiar brand of nuclear hysteria, and not once does she remind us that three reactor cores melted down and released radionuclides over part of Japan just this decade? Has it anything to do with her desperately ill-informed prophesies of catastrophe bearing no resemblance to reality? What about her insistent use of a bogus but frightening chart which everyone else knew was fraudulent? Who knows?

Not that I’m not happy that at least one self-appointed anti-nuclear leader has apparently ceased exploiting – at every opportunity – a deathless industrial accident which happened in the context of a natural disaster that killed thousands. But due to shame over the so far constant fear mongering? Unlikely.

Advertisement

Opportunities to Decarbonise: We Missed You Like Crazy

This was written a little before the publication of Qvist and Brook’s peer-reviewed article that sets out the potential for rapid global electricity decarbonisation through adoption of modern nuclear energy at a rate comparable to what France and Sweden demonstrated – while growing healthy economies – last century. Read it here.

 

Let’s get excited about what nuclear can do for us. It’s about time, after all, and we have a lot of reasons. New designs are available which need only the fuel that is already mined and refined. Serious accidents result in only localised and wholly underwhelming physical consequences by any professional estimation. Adequate management mitigates this risk.

It can also scale at a rate necessary to both potentially help avert fossil fuel commitment in developing nations, and enable the sort of global emissions cut required by IPCC scenarios. Such was highlighted in a paper out of the University of Adelaide, citing national historical nuclear megawatt hour addition rates, annualised and levelised by population. Working with the relatively modest average rate achieved by France in the 80s, an ultra-low emissions system of renewables underpinned with nuclear power was shown to be quite realistic by 2060. No hourly grid simulations necessary. Prioritise all appropriate technology, especially what has been repeatedly proven, and concentrate on decarbonisation instead of technological tribalism.

It’s quite possible that it didn’t need to be this way. As alluded to, there was a time when reactors were being brought online rather regularly, and it’s plausible that the trend didn’t need to end. In this article, the consequences of the potential sustained nuclear rollout were quantified for the US and the world.

In green, we see the existing global carbon emissions levels and in purple is the U.S. carbon emission levels if it continued to adopt a nuclear infrastructure. In red then, as a result, we see the global carbon levels would have been almost 15% lower than current levels.

I invite readers to extrapolate then where the total global carbon emissions would be if all the post-industrialized nations had adopted nuclear power – as their natural technological progressions would have dictated – if it were not for the hijacking of this process by anti-scientific hyperbole by scaremongering environmental activists. Many organizations – such as Green Peace, still ardently oppose nuclear power. And these levels, mind you, are only about one-tenth of what the Atomic Energy Commission was projecting based on demand during the 60s, where at its height 25 new nuclear power plants were being built every year, and the AEC anticipated that by the year 2000 over 1,000 nuclear power plants would be in operation in the U.S.

Inspired by these calculations, I posed a hypothetical for Australia: If, instead of instituting the prohibition of nuclear energy in 1998, the Democrats and Greens had involved themselves legitimately in working towards proven coal power-replacing nuclear energy, with an appropriate focus on safety and environmental protection.

The CANDU EC6 (now offered as the AFCR) is a reactor of appropriate size for the Australian grid, with a track record of swift build times. Assuming only one started per year following a conservative period for IAEA-assisted regulation establishment (cf. adoption in the UAE), environmental impact assessment and so on, an extra year at the start for FOAK, and assuming megawatt-for-megawatt replacement of coal, what would IEA-sourced national emissions intensity look like?

An incontrovertible downward trend, with over 9% extra reduction by 2012. This is indeed roughly equivalent to France’s average build rate as given in the above paper.

How has 25 years of appeasement of the anti-nuclear movement affected Australia’s contribution to heating the planet? pic.twitter.com/dj2z0MMnre

— Geoff Russell (@csiroperfidy) May 13, 2015

This isn’t limited mitigation by favoured intermittent renewables, or a temporary dip due to vagueries of carbon pricing. It is sustained and historically proven climate action which has been deferred since the nineties.

West European countries including the E C may be able to stabilize or reduce C0 2 emissions by early in the next decade through a variety of measures including taxes, energy efficiency programs, nuclear power, natural gas, and renewables…

– IPCC Response Strategies, 1990

Both the potential impacts of climate change and the decarbonisation success of French electricity were known in the nineties – certainly not as immediately available to all as they are now, but known. Granted, nuclear was particularly unpopular, too, but the ideological opportunism of the Greens and Democrats ensured that it stayed that way while the world warmed.

In hindsight, I feel particularly stung by this situation as I was a Greens and Democrats voter since I’ve been eligible.

But this goes back further than France, or climate change. It goes back before the regulatory ratcheting and uncertainty, the escalation in labour costs, the exceptionally impermanent goal posts between which the first nuclear era was forced to kick. (Incidentally, if you thought this ratcheting all happened in the past, think again: the US regulator is considering cutting the utterly adequate current worker exposure limits by 60% – regardless of cost – merely to be consistent with Europe.)

Figure 1

“While there is little difference in materials cost, we see from Fig 1 that the difference in labor costs between M.E. [median experience] and B.E. [best experience] plants is spectacular. The comparison between these is broken down in Table 1. We see that about half of the labor costs are for professionals. It is in the area of professional labor, such as design, construction, and quality control engineers, that the difference between B.E. and M.E. projects is greatest. It is also for professional labor that the escalation has been largest — in 1978 it represented only 38% of total labor costs versus 52% in 1987. However, essentially all labor costs are about twice as high for M.E. as for B.E. projects.”

Table 1: Breakdown of labour costs for nuclear power plants and coal-burning power plants from the 1987 EEDB*

It goes all the way back to the fifties, the era of the Shippingport reactor, the Experimental Breeder Reactor I and a petroleum geologist named Marion King Hubbert. Hubbert was the first to observe how fossil fuels would run out, and make predictions regarding when. Oil companies didn’t like this, but he was famously proved right when US oil production peaked in 1961. It seemed Hubbert wasn’t worried though. He grasped the potential of peaceful nuclear energy. Crucially, he saw breeder reactors enabling the full utilisation of uranium and thorium fuels into the far future, at a time when their supply was believed to be limited. Doubtless, oil companies liked this even less.

…It appears that there exist within minable depths in the United States rocks with uranium contents equivalent to 1000 barrels or more of oil per metric ton, whose total energy content is probably several hundred times that of all the fossil fuels combined. The same appears to be true of many other parts of the world. Consequently, the world appears to be on the threshold of an era which in terms of energy consumption will be at least an order of magnitude greater than that made possible by the fossil fuels.

Today, we know we have plentiful economically recoverable uranium, even assuming the greatly expanded role nuclear energy still needs to play in the coming decades. This uranium is in no way wasted by use in conventional reactors – the resulting recyclable fuel, along with the depleted uranium left over from enrichment, is all fast reactor fuel. Indeed, it has scant other constructive use.

Greens in Europe doggedly pursue the total phaseout of nuclear, apparently above all else; their affiliates in America are equally stubborn. More locally, the last we heard from our Australian Greens was an insular maintenance of their traditional rejection, but apparently without reference to intractable nuclear waste or ecological hazards.

Indeed, further work from our Adelaide authors has demonstrated the future benefits to biodiversity provided by a renewed focus on expansion of nuclear capacity. At this point we should all be wondering who in their right mind would try to justify a prohibition of nuclear technology as part of an Act concerned with Environment and Biodiversity Protection. Even opponents who generalise that it’s “too expensive” or “takes too long” cannot rationally use that to maintain an outright ban. Moreover, that these drawbacks are somehow intrinsic to the technology, under all that ratcheted regulatory burden, is clearly false.

There has been cost associated with penetration of wind and solar in the last decade, and they have contributed to emissions mitigation. There will be cost in maintaining Australia’s legacy hydro capacity. When nuclear is finally legal here, there will be costs. Should we accept the ratcheted, exorbitant costs that have shackled the technology in the west – particularly in aspects where there’s no associated demonstrable benefit? Or can we recognise the urgency of addressing emissions using all the tools in the box and be really smart about it?

To paraphrase the new federal Greens leader Richard Di Natale, we should always be guided by the science. He has rightly made his and the Greens’ support for childhood vaccination unequivocal. The biology behind vaccination is the same that underpins the development of biological weapons of mass destruction. Separating the two is obvious and exclusively pursuing the benefits of vaccination, despite fringe opposition, is straightforward. Why then do Greens have such difficulty with the comparably valid distinction between commercial nuclear energy and the Bomb? How much longer will they treat nuclear the way they do?

 

“Accidents, waste and weapons!” Are you scared yet?

It’s that time again when the stale old narrative gets a superficial rewrite over at The Conversation. This guest post consists of Luke Weston’s reply.

Let’s take a quick look at all the source material that Diesendorf cites in this piece.

• The Guardian
• Enenews (Seriously? What’s next, InfoWars?)
• A couple of pages from Areva, Georgia Power and EdF
• RenewEconomy (Really credible source there, the NaturalNews of energy policy.)
• RenewEconomy again! And again!
• ABC Radio National
• The New York Times
• The World Nuclear Association’s fact page on Generation IV reactors, and Scientific American, neither of which back up the claims being made.
• Extreme science-denier anti-nuclear-energy activist organisation Beyond Nuclear.
• Beyond Nuclear, again.
• The WNA information page on Small Modular Reactors. Again, it doesn’t really provide any substance to back up what it is that you are claiming.
• The University of Sydney ISA report, which explains some of the flaws in the methodology of the Storm van Leeuwen and Smith claims, and shows that nuclear energy is “greenhouse gas free” in exactly the same way that wind energy or solar energy are.
• Diesendorf’s own previous post on The Conversation, which really just parrots the widely debunked claims made by Storm van Leeuwen and Philip Smith on their own non-peer-reviewed website.
• And another of Diesendorf’s previous pieces on The Conversation.
• Anti-nuclear-energy activist organisation the Union of Concerned Scientists, which is clearly an anti-nuclear-energy (and anti-biotechnology) organisation. They don’t check that you’re a scientist when you become a member, by the way, you just go to the website, and the only information you have to give them is your credit card number.

As Hans Bethe puts it in the preface to “The Road from Los Alamos”, “I have also worked with the Union of Concerned Scientists on arms control, but I have never become a member because it also opposes the generation of nuclear power for peaceful purposes – a position with which I do not agree.”

The organisation’s anti-nuclear-energy ideology has been very obvious for many years. Saying “we’re not anti-nuclear-energy” is just like the common cry of anti-vaccination activists that “we’re not anti-vaccination!”

• Diesendorf, Brian Martin and Jim Green’s own “EnergyScience” website, which pushes their own anti-nuclear-energy activism. But why aren’t you publishing any of this in the journals, instead of on your own non-peer-reviewed website?
• Schneider and Froggatt’s “World Nuclear Industry Status Report” website. The name sounds fancy, but it’s still just a couple of activists with their own website.

Mycle Schneider was responsible in 1983 for establishing the Paris branch of WISE, the World Information Service on Energy – an anti-nuclear-energy activist organisation whose coy and mendacious name is essentially the nuclear energy equivalent of the Australian Vaccination Network. The WISE website proudly self-describes Schneider as an anti-nuclear-energy activist. ( http://www.wiseinternational.org/node/1885 )

Antony Froggatt was the Greenpeace International Nuclear Policy Campaigner from 1989 to 1997, as well as the representative of Greenpeace International for Central and Western Europe and the former Soviet Union. The first of Schneider and Froggatt’s “World Nuclear Industry Status Reports” was issued in 1992 as a joint publication between Greenpeace International, WISE Paris and the World Watch Institute. The second and third iterations of their report, in 2004 and 2007, were commissioned by the Greens EFA Group in the European Parliament.

Neither author appears to have any technical experience or qualification in nuclear engineering, physics, or any related discipline. Furthermore, this report suffers from the problem of reducing all nuclear power plant operations, all fuel cycle activities, all state-owned nuclear power operators as well as commercial operators, and all research and development both in the public and the private sector all around the world into this concept of the monolithic “Nuclear Industry”. This is the classic meme of the “Big Industry” – the monolithic big-business conspiracy boogeyman we see often cited by anti-nuclear energy activists, anti-GMO activists, anti-pharmaceutical activists and the like.

Once again, this is nothing more than another non-peer-reviewed anti-nuclear-energy activist website. Obviously there’s nothing genuinely impartial and “independent” here at all. The “World Nuclear Industry Status Report” is not subject to any kind of peer-review or genuinely independent fact-checking or oversight – it’s really just a report published on the website of a group of anti-nuclear-energy activists. It has no more peer review, and no more credibility, than the work that Storm van Leeuwen and Smith have self-published on their own website, for example.

This is a good example of the problem with seeking out only “independent” data that fits the predetermined ideology, and finding “independent” sources that have about as much intellectual integrity as people on the Internet who publish their own passionate reports and research about the dangers of smart meters and wind turbines, or the dangers of vaccination, fluoridation and chemtrails.

• The “Chernobyl: Consequences of the Catastrophe for People and the Environment” book

http://www.nyas.org/publications/annals/Detail.aspx?cid=f3f3bd16-51ba-4d7b-a086-753f44b3bfc1

As the New York Academy of Sciences clearly points out on their website – “In no sense did Annals of the New York Academy of Sciences or the New York Academy of Sciences commission this work; nor by its publication does the Academy validate the claims made in the original Slavic language publications cited in the translated papers. Importantly, the translated volume has not been formally peer‐reviewed by the New York Academy of Sciences or by anyone else.”

It contradicts the best available peer-reviewed science and epidemiology we have concerning Chernobyl, the international work of the Chernobyl Forum etc.

So you’ve posted one peer-reviewed source on this subject in the form of the IARC paper, but you’re apparently not happy with “how bad” they say it is, so you add a non-peer-reviewed source making extreme outlier claims and say that this is a range of credible estimates.

The Yablokov book has been reviewed and substantially criticized by health physicists – for one example of a review in the peer-reviewed literature see Radiat. Prot. Dosimetry (2010) 141 (1): 101-104. (http://rpd.oxfordjournals.org/content/141/1/101

The Int J. Cancer paper you linked to is the only source provided here which comes from any kind of peer-reviewed credible source, and obviously extremely different to what Yablokov et al claim.

What I would say to Mark Diesendorf is the same thing I would say to any anti-GMO or anti-vaccination activist.

Show me the best possible argument for your position (anti-nuclear-energy, in this case) using credible sources that are subjected to, and stand up to, peer review.Show me the best possible, compelling argument that you’ve published in a credible journal for peer review (or indeed, just show me an argument that draws from peer-reviewed sources) and I’ll happily read it.

In a nutshell, to reduce it down to a single three-panel comic strip, this is the problem:

http://chainsawsuit.com/comic/2014/09/16/on-research/

With the exception of one paper in Int J. Cancer, your entire piece is completely lacking any references to peer-reviewed science – plenty of links to non-credible activist websites though. Not one of these is a source with any kind of scientific or academic credibility.

 

Update: Manfred Lenzen, whose rigorous analysis has been repeatedly and selectively cited by this commentator as demonstrating unacceptably high life-cycle emissions for nuclear energy, has followed up with a clear article summarising his own work. He saw fit to include the IPCC’s own chart for emissions from different technology. I have abbreviated it to highlight the comparison of solar PV and nuclear. Mark Disendorf has called loudly for a huge expansion of solar power, but by his logic it has unacceptably high life-cycle emissions. I find it simpler to support both, myself.

 

How To Tell

Replacing fossil fuel combustion with nuclear energy to supply our electricity should hopefully appear a lot more achievable to everyone after today, with the publication of an open access peer-reviewed paper by Qvist and Brook in PLOS One. These are my favourite parts:

Why consider a large-scale nuclear scenario? The operation of a nuclear reactor does not emit greenhouse gases or other forms of particulate air pollution, and it is one of few base-load alternatives to fossil energy sources currently available that has been proven by historical experience to be able to be significantly expanded and scaled up. Large-hydro projects are geographically constrained and typical have widespread impacts on river basins. The land use, and biodiversity aspects of a large-scale expansion of biomass for energy make its use as a sustainable global energy source questionable.

…Between 1960 and 1990 Sweden more than doubled its inflation-adjusted gross domestic product (GDP) per capita while reducing its per capita CO₂ emissions through a rapid expansion of nuclear power production. The reduction in CO₂ emissions was not an objective but rather a fortunate by-product, since the effect on the climate by greenhouse-gas emissions was not a factor in political discourse until much more recently. Nuclear power was introduced to reduce dependence on imported oil and to protect four major Swedish rivers from hydropower installations. As illustrated [below], in the pre-nuclear era (1960–1972), the rise in Swedish CO₂ emissions matched and even exceeded the relative increase in economic output. Once commercial nuclear power capacity was brought online, however, starting with the Oskarshamn-1 plant in 1972, emissions started to decline rapidly. By 1986, half of the electrical output of the country came from nuclear power plants, and total CO₂ emissions per capita (from all sources) had been slashed by 75% from the peak level of 1970.

Importantly, the paper does not seek to neglect the contributions from other technologies. But it does redress the habitual exclusion of any nuclear potential in the bulk of “energy plan by this-or-that year” scenarios – which undeniably tend to optimistically favour dilute renewable sources like wind and sun.

Oskarshamn NPP. 3 reactors. 10% of Sweden’s power. Beautiful spot.

But with all these studies, models and scenarios, how to tell which are realistic? How, without a nerdy interest in terawatt hours and capacity factors, can a normal blog reader decide which ones are really just written to reinforce a preconception? How about these for pointers:

• Proposed technology rollout rates are given in kilowatt hour per person per year, or an easily convertible metric, as in the Qvist and Brook paper. This allows quick comparison between technologies, historical rates, countries and so on.
• Technology tribalism. Failing to consider nuclear’s role, while succeeding in heroic optimism for other technologies, speaks directly to the authors’ bias (and even more clearly when an author’s bias is taken to ridiculous extremes elsewhere).
• The authors have no problem with consulting industry professionals and scientists who work in the relevant field.
• The authors keep coming back to carbon emissions reduction. Alternatives to coal, oil and gas are supposed to reduce emissions. Sometimes one has to dig deep into a “100% Renewables” study to find out where it connects to “0% Fossil Fuels”.

On that last point, wouldn’t it be something to see environmental non-governmental organisations – routinely so vocal regarding climate action – promoting this latest historically-grounded analysis as part of a technology-inclusive, rapid fossil fuels phaseout?

The results indicate that a replacement of current fossil-fuel electricity by nuclear fission at a pace which might limit the more severe effects of climate change is technologically and industrially possible—whether this will in fact happen depends primarily on political will, strategic economic planning, and public acceptance.

 

The Wind, The Sun and The Nuclear – Part 3

In Part 1 we evaluated three quite different, ultra-low emmission power generating technologies that are more or less feasible in South Australia based on their expected overall performance: an ideally-located windfarm; treatment pond-cooled, efficient solar photovoltaics (PV); and the commercially-offered fuel-recycling PRISM small modular nuclear reactor.

Image credits: windturbines.com, adelaidenow.com, midweststudios.com

In Part 2, it became apparent that the relative popularity of each technology, and the notable and concerning reluctance of women to support modern, safe nuclear designs reflects a failure to communicate accessible, accurate and pertinent knowledge to the folks who are going to need it in the future. Energy can be a dense subject but comprehension beyond cents per kilowatt hour (kWh) or choosing solar instead of fossil fuels becomes necessary as we get involved in deciding how to clean up our supply while providing at least as much access and opportunity for our children as we have enjoyed.

As such, in this final part – more of an appendix – we can highlight a few more unnavoidable consequences of needing all this energy, and the technology mix we support for providing it. We’ll just worry about electricity, which meets a substantial proportion, though not all, of what we require in our day-to-day lives. And we’ll bear the challenge of future climate disruption – which must be met with ample sources of energy and the resilience they confer – firmly in mind as something we should not leave to our children to address.

The technology, the machinery, needed to convert our preferred energy source into electricity, needs to be built out of materials. This has never been more clearly illustrated than in this 2013 Scientific American article. This is the graphic:

The article mentions “hidden costs”, but it’s usually more that the costs are overlooked. Yet it is intuitive that the sophisticated and highly purified electronics underlying solar PV technology would charge a price in metals required, such that the massive circle for silver – plus those for aluminium, tin, copper and zinc – do make a lot of sense. In case it’s not clear, the size is an indication of how much more metal will be demanded when we want a kilowatt hour just from solar instead of from the average global electricity mix.

What about silicon? Fortunately, the required quartz is effectively inexhaustible, though the energy-intensive refining is substantial.

On this basis, the sort of wind energy we’ve looked at might seem preferable, though as before it’s important not to forget the other characterisitics we’ve already considered: capacity factor, average availability to meet peak demand, and so on. Pursuing a reliable but ultimately decarbonised electricity supply isn’t necessarily the same thing as aiming to minimise the amount of materials used. However, it will have to be a consideration, as described in a 2013 commentary in Nature Geoscience.

The construction and operation of technologies that harness renewable
sources of energy will consume large quantities of raw materials. The growing demand for rare metals, including selenium and neodymium in photovoltaic panels and wind turbines, risks derailing the shift to renewable energy. However, wind turbines (and photovoltaic panels also require enormous amounts of common metals such as iron, copper and aluminium, as well as sand and industrial minerals to make concrete and glass, and hydrocarbon derivatives to create resins and plastics.

…Humanity faces a tremendous challenge to make more rational use of the Earth’s non-renewable raw materials. The energy transition to renewables can only work if all resources are managed simultaneously, as part of a global, integral whole. Designs of new products need to take into account the realities of mineral supply, with recycling of raw materials integrated at both the creation stage and at the end of a product’s life cycle. Research is crucially needed to anticipate the total material requirements and environmental impacts of any new technologies.

A case can be made for more metal production near centres of demand, similarly to the locavore movement that proposes looking closer to home for our food. It seems unreasonable to shun green beans grown in Kenya while using copper from the Congo.

The authors rightly stress the potential for recycling of materials, but do not ignore the energy requirements involved, nor the vital research and development still needed to make it at all realistic.

What they do not acknowledge is the role of nuclear energy, both as a potential supply for these future recycling requirements, and also as a partner to the renewable technologies that are demanding all of this refined material. Take another look at the SciAm graphic. The bubbles for nuclear are for conventional reactors, the ones which consume a few percent of the uranium fuel. Even at this efficiency they are brilliant for reliable and safe electricity supply. But we have been looking at a fast reactor which is designed to run on both spent nuclear fuel and the refined uranium left over from enrichment. It can recycle this fuel until virtually every kilowatt hour is extracted. Even with the steel, copper and everything else used to built it, what would its materials requirements look like?

It would have to be at least this good.

One other thing, and this ties in to the unavoidable mining and recycling which our Nature authors have warned us about. Technology wears out, and at some point must be decommisioned and replaced. This is a looming problem for conventional nuclear plants, recognised especially in countries like the UK where a large number of reactors are planned to help with replacement. But for much of the rest of the western world commitment to new nuclear is largely lacking. So what are the alternatives? Well, the same lifespan issue comes with solar and wind, only it’s even more limiting. The efficiency of PV panels is known to degrade at a fairly constant rate, such that we can’t expect more than 90% of a solar installation’s efficiency after 20 years, and possibly less. But as any rooftop system owner knows, it is the supporting hardware like the inverter that is expected to wear out first and require outright replacement.

The International Energy Agency highlighted data from their 2014 World Energy Outlook that considered what this means for wind.

Pay attention to both axes. By 2040, the global share of generation from wind is expected to be visibly levelling off at well below 10%. This isn’t because of lack of popularity, or capital-inflating heavy regulation as suffered by nuclear energy (which was still nearly 11% in 2012). It’s because wind turbines – necessarilly exposed to the weather to function – have an expected lifetime of twenty-five years. After some inescapable future point, at a respectable but still relatively low global penetration, countries can expect no better than to be, on average, building wind farms no faster than they’re tearing them down.

I don’t know anyone who likes the implications, but in my view our children will have enough to occupy their energies without being committed to “treading water” in the replacement of their sources of electricity. Maybe it won’t come to that, but it depends heavily on how informed we want to be now in the choices we make for their sakes. Yes, reactors too come up for renewal but their supreme energy density makes all the difference.

Nuclear energy is estimated to provide 1000 watts per square metre.

The issue is that there’s good reason to expect the shares of solar PV and wind to meet quite clear material limits, while the traditional limits on nuclear are at best arbitrary and at worst populist, but in either case may ultimately serve to restrict resilience for subsequent generations – unless ours stands up for the arithmetic.