Comparing Like for Like

Since you’re reading this blog, you’ve almost certainly encountered this claim:

We don’t need nuclear because we can use renewables.

For renewable sources like geothermal and hydroelectric this may apply, since they can provide guaranteed generation around the clock. But the former has been abandoned in Australia and both can meet only a small portion of our future requirement for climate-friendly electricity.

But in truth the claim invariably refers to solar and wind, not all renewables. For a scalable technology like solar power to hypothetically meet such a demand profile, storage is implicitly included, or at least invoked upon inquiry. David Green of Lyon Solar described it well:

If we really want to address the penetration of large-scale renewables – and not just be able to satisfy the market you can connect large-scale batteries onto the grid – you need to be able to demonstrate that power generated from renewables can be dispatched with power from the batteries like base-load power, so it’s not creating problems.

However, the size of Lyon’s projects instead indicate a peak demand role in the power market. The megawatt hour (MWh) capacity of their batteries are too limited to supply constant overnight power (not to mention the unlikely economics of supplying at low overnight prices). So the question still remains, what would that look like, and how would it compare to the modern nuclear energy technology some believe it supercedes?

Simplified capital costs over time

In this thought experiment, we’ll use

By multiplying the number of 50 MW class solar plants to ensure that excess generation above this number equals overnight requirements, an idealised “solar+storage plant” can be modelled. Slightly more than 3 Broken Hill-sized plants would be needed but we’ll assume three for simplicity. Similarly, operational costs are excluded for both technologies.

Thus, we can compare assumed overnight capital costs for a NuScale plant, 60 year design life, and twelve solar+storage plants which would hypothetically match its nameplate capacity. As mentioned in the Finkel Review, the lifespan of lithium ion technology is 10 years so the cost of regular replacement has been factored in, in addition to renewal of the solar panels after 30 years (assumed to be half today’s cost).

When the capabilities of the two technologies are hypothetically levelised in this simplified way, it appears that the specific argument on cost is reversed.

Estimated required land area

The area of Broken Hill solar plant is 140 hectares. Thirty-six such plants will need about 5,000 hectares, only slightly smaller than the area of Sydney Harbour. However they don’t all need to be co-sited.

NuScale’s plant, which is now under formal design and licencing review by the US Nuclear Regulatory Agency, will cover a little over 36 hectares, including its maximum required emergency planning boundary. It can essentially be situated anywhere that would be suitable for an industrial facility, as water is not necessary for operational cooling. Notably, other options may well be available for the 2030 timeframe.

Material requirements levelised by generated energy

The US Department of Energy 2015 Quaternary Technology Review estimated various levelised material requirements for major electricity sources. Additionally, silver and uranium requirements can be authoritatively sourced. Charting these estimates illustrates the difference in amounts of materials needed by solar and nuclear, for the same amount of electricity produced.

This doesn’t include the materials like lithium, graphite and cobalt needed for the batteries, which aren’t a power source. It is assumed that materials needed for iPWR (intergrated pressurised water reactor) type SMRs are sufficiently similar to conventional PWRs.

This thought experiment attempts to match solar energy capability to that of nuclear. It hardly needs to be said that the reverse is a much less valuable exercise. Cyling a collection of SMRs daily between 0% and 100% output (with considerably less in poor weather) makes little sense in many ways, not least of which is the consequence of diminshed emissions abatement in a system still overwhelmingly supplied by coal and gas combustion. The whole benefit of including nuclear energy sources is they represent a drop-in replacement for dispatchable fossil fuel fired generators.

There are also commercial scale examples of battery storage paired with wind farms, such as the facility in Rokkasho, Japan. The particular battery chemistry used – sodium sulphur – was recently evaluated in California with sobering results.

We won’t compare the potential emissions savings since authoritative research puts solar and nuclear both at desirably low factors. However, the extra material intensity of batteries may contribute dramatically to lifecycle emissions, depending largely on their country of manufacture.

Solar plants and battery modules can be installed rapidly. In contrast, a certain first time regulatory cost and lead-time for that nuclear plant is unavoidable. Yet it isn’t necessary to overstate this hurdle. In its submission to the South Autralian Nuclear Fuel Cycle Royal Commission, Engineers Australia observed that ANSTO’s OPAL research reactor is of similar size but greater complexity than an SMR unit, and concluded:

The OPAL development at Lucas Heights provides an excellent management example for an SMR nuclear power station in South Australia. Extensive international guidance is available from the IAEA to assist in establishing a nuclear power program…

Australia already has a competent and very well managed regulatory regime with staff with wide international experience. Many of the ARPANSA staff have extensive experience in operating nuclear power plants both civil and military. There is no fundamental reason why the ARPANS Act 1998 cannot be amended to include the regulation of nuclear power in Australia.

The results illustrated here should not be taken as any reason not to build solar, especially paired with storage so as to shift generation to meet high demand, like Lyon Solar’s projects. The importance of this was underscored in the Finkel Review.

However, excluding nuclear energy, with its specific supply profile that can’t realitically be emulated by a variable source like solar, is probably unjustifiable on grounds of cost, land use, material intensity or regulatory challenges. This isn’t intended to downplay the regulatory and public education headwinds the technology faces, but rather to emphasise how important it is – considering the results here-in – to face them now and seriously begin the process. As the Engineers Australia submission noted:

The utilisation of a mix of all low emissions electricity generation technologies will be essential to achieve long-term greenhouse gas emissions targets.

What can be more serious than achieving targets that are aggressive as possible with everything available?

 

A Young Person’s Guide to Nuclear Advocacy

This article is now a page here, where it will be updated to include further useful resources.

So you want to advocate for nuclear power? You liked the look of thorium, did  your research, and have concluded that conventional nuclear power has been unfairly maligned since the 70s? You saw Pandora’s Promise and can’t fathom why we don’t have the IFR? Or maybe you lie in bed at night wondering what sort of climate-disrupted, energy-starved world your young children will have to face in twenty years time?

Everyone’s reasons and journeys are different, but the necessity of nuclear energy will effect us all the same way. You already have allies in physics and history, and the call for rational energy planning grows steadily stronger.

lego

THE ENERGY

Before doing anything else, you need to get comfortable with your units. I prefer terawatt hours per year (TWh/yr) because a) everyone’s heard of kilowatt hours, and b) it is an equivalent of the more familiar megawatts (MW – there’s a million MWs in a TW) that electricity generators supply, but it indicates that average yearly supply and capacity factor have been considered. You already understand capacity factor – it’s one of the many vital metrics where nuclear energy excels. So, when considering the average annual electricity a given plant, like Vogtle 3 & 4, will supply, we can reasonably assume a capacity factor of 0.9 or 90%, multiplied by the combined AP1000 units’ nameplate capacity of 2308 MW (= 2077.2 MW average) then by conversion factor of 8766. The product is 18.21 TWh/yr, and through similar arithmetic nuclear and alternatives can be somewhat levelised for comparison as sources of electricity.

That capacity factor is the kicker. While nuclear plants can be operated at lower capacities, the negligible fuel costs (a consequence of the sheer potential energy density of actinide nuclei) dictate that economy is maximised by minimising downtime for maintenance and refueling. Finland, a nation that embraces nuclear for its growing energy needs as well as effective carbon abatement, boasts a 95% capacity factor for its reactors over the last decade. There isn’t another scalable source of low-emissions power that can provide such reliability – not even hydroelectricity, which is strictly constrained by suitable location. This isn’t to say that load-following is unfeasible, indeed it is becoming a noted feature of newer reactor designs.

frenchramp

French reactors load-following at 70 MW per minute back in April.

THE MESSAGE

While it is not unknown for opponents to be swayed through online discussion, your arguments are largely for the benefit of current and future readers more than the sake of changing your immediate opponent’s mind. This is because Facebook pages and comment sections are public and searchable. It speaks to how oblivious some opponents are regarding their bias that it won’t occur to them to take the debate to private email. Invariably, their selective arguments will merely be opportunities for you to respond with appropriate examples, analysis, literature, infographics or conclusive factual rebuttals and the casual forum reader can judge for themselves. Remember, you have both physics and history as allies.

This is most pronounced on twitter. Despite the fast pace and length limitations of the discussions, even when you’ve been muted or blocked by obstinate opponents, the fact that you have clearly put your case is preserved.

twi

The dominant narrative in Australia has been:

  1. Being Green, alternative or otherwise environmentally aware is to be anti-nuclear by definition;
  2. The wisdom of physicists, engineers and other nuclear-related experts – even international peak bodies –  is naturally dismissed as corrupted and of similar reliability as testimony from fossil fuel or chemical corporations;
  3. Radiation is exceptionally dangerous, end of story. We cannot risk the imagined catastrophe of a nuclear accident in Australia (no matter how small the risk, or how large the contrasting benefits).

This sort of thinking was kind of forgivable in the 80s, after Chernobyl, when the consequences of such an accident (actually impossible with reactors of Western design) were still unknown; when the science and early signs of climate disruption weren’t yet on the public radar; and when the example of France had not yet proved that rapid exit from national fossil fuel use for electricity was entirely feasible.

geoff russell

But it doesn’t cut it any longer. Chernobyl didn’t cause the carnage predicted at the time. Fukushima even less so. And the psychological harm to an affected population by fearmongering in place of evidence-led education directly results in panic, despair and destroyed families.

There is no obligation whatsoever to let bad information stand.

And the Bomb? Conventional electricity-generating power reactors are not used to make bomb material. Fact.

THE RADIATION

radioactiveme

I won’t lie – this is the tricky part. Nuclear radiation may fundamentally be a natural phenomenon, but it is still something that human senses simply can not perceive. If you look around, you can concentrate and be aware of everything around you… but can you feel the negligible fraction of a microsievert of natural, background beta and gamma radiation hitting you at this moment? Ionising radiation, including also X-rays and ultraviolet, is like that. You don’t feel its effects in your cells, but you may know later if you had too much exposure, such as peeling skin after too much sunshine.

Conventional understanding since the 50s has dictated that all this harm – the cell death or DNA damage – is cumulative and that there’s no safe dose. On this assumption, stringent and expensive regulations are levied upon nuclear power, medicine and other uses, and the natural response to mishaps or even the fear of accidents is to tighten them further.The formulae for estimating dose get misapplied to predicting deathrates from radiological release – perfect ammunition for those unscrupulously opposed to nuclear energy.

Again, possibly a forgivable assumption decades ago, but the Taiwan Apartments, the Goiânia accident, the Sands of Guarapari and many other examples including vast medical experience are the exceptions that appear to be the reality of the situation. While the biochemistry is fascinating and the multitudes of isotopes and applications are exciting, scientific understanding is secondary to the overwhelming message here: radiation is probably safe at low doses and is definitely not the devil we’re told it is. Precautions are sensible, but don’t freak out! But certainly, as long as you’re interested it is a good idea to get comfortable with becquerels and sieverts, their common magnitudes, their various sources, and the difference between a negligible and a dangerous dose rate.

This is the idea that we were born in a sea of radiation, we evolved in a sea of radiation, we should expect that our bodies should have some sort of underlying protection from radiation…

So given radiation isn’t an exceptional danger, why oppose properly regulated, oversighted, peaceful nuclear power and medicine?

THE RESOURCES

Atomic Insights – maintained by Rod Adams, the “favourite uncle” of nuclear blogging.

Hiroshima Syndrome – maintained by Leslie Corrice, with a focus on busting myths about radiation and the Japanese situation.

Brave New Climate – vast nuclear information resources with an Australian perspective from Barry Brook and guests, with particular emphasis on the IFR.

Patrick L. Walden at TRIUMF – many factual references from a nuclear physics professor.

Pandora’s Back Pages – Ed Leaver provides citations for all the information presented in Pandora’s Promise.

I have to include PopAtomic Studios and Suzy Hobbs Bakers’ artistic, human-focused inspiration.

This list is nowhere near exhaustive, but I present it as the material I often rely on when putting my case. I must also recommend purchasing copies of Radiation and Reason and Greenjacked! Please feel free to add further references in the comments.

Now go forth and change some minds! However, I mean human minds, just like yours. Facts, analysis, commentary and reasoning will take you far, but it is vital, crucial that you also understand the other side.

The propagandist’s purpose is to make one set of people forget that certain other sets of people are human.

This is advocacy, not a propaganda. Use rhetoric, not polemic. And don’t challenge anyone if you’re not prepared to challenge yourself even harder.

Shameless Optimism: An Article from June, 201X

This is an entirely fictional and hopelessly optimistic newpaper article from around the end of this decade, assuming certain spontaneous outbreaks of rationality and determination.

In what may be remembered as its most historic moment since Federation in 1901, the South Australian parliament yesterday voted almost unanimously to approve the final regulations pertaining to the proposed Inner Harbour IFR Project.

The recently minted Premier was actually grinning on the steps of parliament. “As you know, this modern, carbon-abating power plant was something I took to the last election as an answer to South Australia’s deteriorating, fossil-dominated electricity supply.

“My party listened to the fresh sentiment of the people, and it listened to business, and it listened to our renowned academics, and it listened to ANSTO, and it listened to the IPCC.

“We are a state of firsts, and Australia’s first 620 megawatts of nuclear waste-burning power will be built right here in Adelaide, with local contractors and local jobs.”

The resources minister was equally optimistic. “The partnerships we have with all of the new and planned reactor operators in Korea, South America, the US and China to supply high quality uranium will ensure sustainability of the industry as it steadily replaces coal mining as our dominant energy export.

“Accepting it back after use for recycling is just common sense.”

After shaking hands with both the Premier and the Opposition Leader, the director of the project coordinating body, South Australian Integral Fast Energy Sector Transition (SAIFEST), said, “Since the groundswell overturning of the federal prohibition on nuclear power, part of our tireless work has been the adaptation of the very best regulations and guidelines from the most successful foreign nuclear energy programs, always with an eye to what is most suitable for Australia’s rather unique circumstances.

“Yet even I hardly dared dream it could all happen this rapidly.”

The regulations also pertain to the expansion of mining, the nascent nuclear fuel enrichment facility and the planned Intermediate Fuel Repository, for which suitable sites have been narrowed to two contenders.

The plant, which was controversial when first proposed, has enjoyed nearly two years of widespread support as industry workshops continue to tour the state and communicate the realities of the benefits and risks of new generation nuclear power.

“If you asked me back in 2011, I’d have laughed at you,” said one mother at her suburb’s community centre, standing in front of the now well-known glowing PRISM model.

“But the Fukushima accident still hasn’t caused the death they told us it would, just like the radiation experts said all along. And that sort of meltdown just can’t happen with this reactor, can it?”

1400558659547

This popular support from an already nuclear-curious state was undoubtedly cemented when 12-year old Jayden Ashley of Parafield won the grand prize for his entry in the Main Containment Building design competition.

An executive for the international vendor commented at the time that it was so instantly iconic and intuitive, she didn’t know why they hadn’t already thought of it.

“Of course we’re extremely glad the legal framework’s now in place and that the government continues to embrace the hyper-modernisation of South Australia’s generating capacity,” the vendor’s Adelaide office said over the phone.

The construction industry consortium formed to coordinate site preparation, contracting and module assembly took the news in its stride.

“From the start we’ve proceeded on the understanding that the new regulations are there to facilitate the scheduled completion of this project,” their spokesperson said.

“It is already positively impacting the disused manufacturing capacity of this city, and will shortly begin providing jobs for thousands of people who not long ago still weren’t sure what they were going to do as the auto industry left the country.”

“These are safe, well-paying jobs that will set many of our members up for secure employment in further construction around the country,” echoed the construction union secretary this morning.

The local cement industry, already contracted to supply materials for the basemats, containment and related structures, anticipated a new, sustained era of competitiveness.

“The clean, reliable electricity will boost productivity while lowering our overall process emissions,” said a representative.

“We’ve also been in talks with the reactor fuel recycling people regarding the products they’ll separate from the partially used fuel.

“A lot of people don’t realise that we use isotopes like californium and caesium-137 to ensure the high quality of the concrete that their houses sit on.”

The president of Port Adelaide’s independent community monitoring task force for the project was confident that the regulations were adequate. “Our group was set up and funded to ensure that the plant will be serious about honesty and transparency when it comes to nuclear safety, especially close to an established suburb and a busy harbour.

“I still don’t know if what they say about low-level radiation is true or not, but even if a leak is unlikely or harmless the operator will answer to the community if it lets it happen.

“Even then, though, we know that we won’t have to run for the hills.”

He added, waving in the direction of the old MFP site, “I was definitely anti-nuclear in the 80s and 90s but new designs have addressed most of my concerns, and of course back then no one was worried about global warming.

“We’ve just had our hottest year ever! This plant will make electricity without the carbon, while putting our city at the head of the solution to 100,000 year nuclear waste.”

Adapted from historical artwork of the Clinch River Breeder Reactor

Artist’s* impression of the IFR plant, featuring the proposed containment design.

“I literally can’t wait,” said a first year nuclear physics student in the University of Adelaide Hub Central.

Nuclear energy-related courses have seen a meteoric resurgence in the last two years, with Adelaide’s first graduates expected next year.

“This is what I wanted to do since high school, since I learned that we need to act urgently on climate change.

“South Australia has great sun and wind resources but we simply can’t rely on them to ensure prosperity and actually replace the dispatchable fossil-fuelled electricity we’ve been using till now.

“These reactors can be built where the demand is, using the existing connections.

“Sorry, I just gave a presentation on this stuff. But the arithmetic doesn’t lie.

“Building IFRs and getting paid to accept the fuel for them will keep long term electricity supply reliable and cost-competitive: which provides opportunity to work locally on improving other renewable energy sources like tidal and algae biofuels.”

SAIFEST’s director said later that he had discussions scheduled with metal companies and manufacturers regarding possible new plant locations neighbouring the reactors. “High energy industries don’t want to ignore the problem of emissions any longer,” he commented.

“They will go where the cleanest, most reliable energy is.”

 


 

*I am obviously not an artist.

 

James Hansen, BA, MS, PhD

I admit to not knowing about James Hansen until I encountered him amoung many other experts over at DecarboniseSA, and subsequently learned of his fundamental contributions to the study of our changing climate. He recently released a draft opinion essay dealing with the required global approach to nuclear power in the context of urgent internalisation of overall carbon emmissions: Renewable Energy, Nuclear Power, and Galileo.

“…my suggestion to other scientists, when they are queried, is to point the public toward valid scientific information, such as the “radiation 101” page written by Bob Hargraves. “Sustainable Energy – Without the Hot Air” by David MacKay lets the public understand calculations as in the footnote above [see essay], thus helping the public to choose between renewables and nuclear power in any given situation – there is a role for both.”

The essay is clear and accessable and ideal for anyone who is still unsure what to think about climate change, nuclear power, or both. It may challenge what you thought you know; by all means investigate further. But be fair to yourself and stay up at the high academic standard from which professional scientists like Professor Hansen profer their knowledge.

Generation IV

This debut post is a concise summary of the modern approaches to realistic, efficient nuclear power that heed traditional safety concerns and cost effectiveness, which I wish to promote as the clean, modular sources of baseload electricity for the near future.

MSR

The molten salt reactor is basically a chamber containing high temperature, unpressurised liquid phase fluoride salts, with a moderation mechanism such as control rods, and inputs and outputs to access the generated heat. In the design built and tested in the 1960s at Oakridge National Laboratory, a mixture of fluorides of lithium, beryllium and zirconium was used as the coolant, containing uranium fluoride as fuel. It was tested for a total of 6000 hours (250 days) without incident.

The striking advantages of this approach to nuclear power would have been realised in the following phase of research, had funding been continued. The MSR fissioned U-235 (and then U-233) to generate heat, but a further layer of subtly different fluoride coolant was intended to “blanket” the main coolant chamber such that it was exposed to the neutrons from the reaction. This blanket would contain thorium fluoride as the fertile fuel.

Thorium exists naturally as a single, ubiquitous radioactive isotope. It is responsible for much of the harmless background radiation in soil, sand and rocks which nobody spends a second’s thought on. Thorium-232 would “breed” uranium-233 after capture of a neutron, and it is this form of uranium which would fission to provide further neutrons to sustain the chain reaction. Used in this way, molten salt reactors would rely on an abundant primary fuel that is currently considered a worthless by-product of rare earth mining, and which, in principle, could be concentrated from soil or rock from nearly anywhere. Moreover, the homogenous nature of the liquid fluoride fuel ensures essentially total conversion: every watt of thermal energy would be produced.

Other actinides, in suitable molten salt form, could also be used to fuel the MSR, hence this technology represents an avenue for permanent disposal of waste and weapons-grade material. In addition, intrinsic passive safety features promise “walk away safety”. For a start, the reactor fuel is already in a high temperature (>650C), molten state, so the concept of “nuclear meltdown” is entirely circumvented. The density of this liquid in the original experiment was observed to oscillate so as to accelerate and decelerate the chain reaction and “load follow” the energy demanded of the reactor. As for emergency shutdown, an outlet pipe at the base of the reactor is cooled by an electric fan which keeps a “plug” of salt frozen within. Failure of the system would cause this to melt and allow the molten salt to drain harmlessly into basement storage tanks. Finally, the near-atmospheric pressure of the reactor means no large, thick concrete containment is necessary.

The reaction heat is exchanged into a separate salt or steam loop to drive a turbine for electricity, but the high temperature is also ideal for chemical and industrial process heat, such as water desalination. Although this reactor concept is being promoted in the U.S. as LFTR (Liquid Fluoride Thorium Reactor), a major Chinese research centre has dedicated a group of about 300 workers to establishing the MSR technology based on the Oakridge results.

Flibe Energy

Transatomic Power

Terrestrial Energy

IFR


The integral fast reactor is envisaged as self-contained reactor, generator and fuel recycling plant. It is specifically based on liquid metal-cooled fast breeder reactor technology, as opposed to traditional water-cooled thermal reactors.The enriched uranium and other fuel derived from spent nuclear or weapons-grade material is fabricated, as oxides, into solid fuel along with sodium metal. At operating temperature the liquid sodium, as well as circulating and transferring the reaction heat, fills the voids left by fissioning material and acts to maintain steady neutron density.

These neutrons interact in the fast spectrum, with much the same energy as they had when they were released. This results in breeding of further Pu-239 from fertile U-238, and thus the eventual consumption of virtually all the nuclear fuel (in comparison, a traditional light water reactor will use less than 1% of the solid fuel material). The resulting spent fuel is recycled in a pyro-processing facility, powered by the reactor, where remaining useful isotopes are extracted and incorporated into new fuel, and actual waste is treated for long term storage.

The most promising IFR is known as PRISM (Power Reactor Innovative Small Module), the result of extensive testing of the liquid sodium-cooled reactor concept in the form of the successful Experimental Breeder Reactor II, which ran from 1965 to 1995. Actual scenarios were demonstrated where coolant flow was shut off at full power, resulting in natural expansion of the reactor liquid and shutdown due to low enough neutron density. Other passive safety features are provided by refuelling and generating mechanisms integrated into the reactor itself under the sodium coolant, which is securely sealed from interaction with oxygen or water. This also implies a modular design philosophy which will enable assembly line production reminiscent of passenger aircraft construction. PRISM is ready for assessment by various countries’ regulatory authorities; China is known to be constructing a similar reactor.

Similiar, modular concepts include:
The ARC-100
The Energy Multiplier Module

SMR

Small Modular Reactors are a broader class of modern reactors which generally offer an output under 3-500 MW, integrated coolant circulation, safety systems and power generation, and rapid assembly line production. Some approaches boast the need for infrequent refuelling. Strictly speaking Generation-III+ technology, among the many designs, the Westinghouse SMR is somewhat like a miniature model of the state-of-the-art AP1000 power plant, many of which are currently being erected in China. The increased economies of scale and standardisation of components which do not require prohibitively large production facilities promise an increased power output per unit area of footprint and per total fabrication costs.

Update December 14th: The SMR design to be prioritised through U.S. federal funding is the NuScale design, an incredibly portable reactor concept with a nominal electrical output of 45 MW. Read about it here.

Here is an animation of the construction of the first Babcock & Willcox mPower plant. The mPower will be rated at 180 MWe per module.