Anti-Reality. Anti-Nuclear.

This is a sort of personal one, folks.

Growing up in Australia, my experience informs me of a prevailing anti-nuclear sentiment which tends to cling like a habit. I think I remember asking about what was going on when this Chenobyl thing was smoking away on the tv, and received a basic explanation couched in concern over general safety and unrelated events like Hiroshima and the Cuban Missile Crisis.

My father’s old watch had a radium dial. I’d nick it at night to stare at the glow. Despite being fascinated with nuclear energy as I grew, the habit remained, preened by the weapon testing efforts of the French in the 90s, the concerns over long-lived waste. I read Niven and Pournelle’s Lucifer’s Hammer and remember being surprised and intrigued that not only was the fictional San Joaquin nuclear power plant depicted as entirely benign, its functional survival became pivotal to the survival of civilisation.

Then there was the controversy around the proposed waste dump in my state. Fortunately, I’d started uni by that time and could consult lecturers on the matter. Turned out there was radioactive waste stashed under the chemistry department. I finally faced my first fear at a proper personal level: the radiation wasn’t doing anyone any harm.

If you are worried about radiation (like what you might imagine is floating around in those pictures of deserted Fukushima villages, or out to sea east of the crippled power plant), please indulge me for a minute, and imagine not being worried or afraid of it.

Now, ask yourself, how much you actually know about nuclear energy?

I ask myself this all the time, and my only response is to seek out more information. After all, you can only know something if it is true. I found a blog by a retired professional which brings together much of what I have absorbed disparately via comment threads and web surfing over many years.

The way I see it, you can make do with the old way of absorbing news, which will essentially always pander to the ingrained habit of nuclear scepticism – why risk putting readers off and losing advertisers? Or you can treat that as a launch pad and delve for the unfiltered facts which will actually serve to inform you and benefit your knowledge. There is always confirmation bias to be wary of, but that is why, despite the now-obvious urgency of this issue, it has taken me years to reach this position. And confirmation bias swings both ways, remember.

So if the first time you thought hard about nuclear was after the Touhoku earthquake and tsunami, and found yourself freaking out about radioactive oceans, there is a sober voice to calm you. Ever wanted to know what actually happened in the Ukraine? It’s sort of hard to believe that there are several plants like Chernobyl still operating without incident, let alone the fact that the other three reactors at the site carried on generating quite safely long after the disaster. But somehow, they were safe enough.

Even Three Mile Island seems more like a cautionary tale in the success of redundant safety systems of Gen-II reactor designs when presented by someone who understands everything about it.

Another great communicator is Gordon McDowell. I’m proud to have helped crowdfund his upcoming documentary.

There’s a common brand of environmentalist who is ready to quote respected, consensus scientific conclusions on the likelihood and consequences of climate change due to our civilisation’s GHG emissions, but then perpetuate misunderstanding and paranoia regarding nuclear power and the nature of radiation with little or no respect for the facts presented by comparable scientific institutions, nor the experience of professionals such as our blogger above. I’ve noticed something about such hypocrites: they’ll never ask you why you’re in favour of nuclear.

The information I’m sharing is about being consistent in these issues. I hope it gets you thinking. And more importantly, I hope it gets you knowing.

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But, Fukushima

The Great East Japan Earthquake (as it is known locally) and the resulting tsunami in March 2011 officially killed 15,883 people, with 2,652 still missing. 6,149 people were injured. Save the Children reported an estimated 100,000 Japanese children were displaced from the security of their homes as their world appeared to crumble. A large populated area, well north of Tokyo on the east coast of Honshuu, already devastated by earthquake and monster waves was evacuated of roughly 300,000 residents after containment failed at a forty year old nuclear power plant.

Cosmo oil refinery fire in Chiba. Six workers were injured.

Pictured: Not Fukushima

But, Fukushima.

As a result, approximately 1,600 people have died before being able to return home. Importantly, these deaths were not related to radiation exposure. In fact, the World Health Organisation has stated that no statistical increase in mortality is to be expected due to leaked radiation. It is possible that the extensive evacuation saved many residents from higher or longer-term radiation exposure, which may have ultimately resulted in a worse outcome. But it is also quite possible, indeed entirely probable that even so, nothing like 1,600 people would or could have died.

But, Fukushima…

Estimates of actual leaked radioactive material vary fairly widely, and are reported in tera- and petabecquerels, which give a technical indication of how much radiation people could potentially be exposed to. These numbers correspond to actual masses which have been spread finely over land and sea, so when one considers that the reported leak of 15 PBq of relatively dangerous caesium-137 for example (with a radioactivity of 3.215 TBq/g) is due to no more than about 4.7 kg of the isotope, which mostly is expected to have settled within the 20 km restricted zone around the plant, a different perspective of the risk of excessive contamination to individuals, and the scale of the clean-up process, is apparent.

But, Fukushima..?

Let’s keep a sense of perspective. I mean, there’s this guy, somehow. And the fact that the Pacific already contains relatively large amounts of Cs-137. (and K-40, and U-238, and Th-232…) So, no, not Fukushima, if the implied question was should nuclear power be expanded to meet electricity demand and mitigate pollution and anthropogenic carbon dioxide.

After spending 2 years enacting energy austerity and scrambling to expand natural gas electricity generation, Japan is being patted on the back for erecting a wind turbine off the Fukushima coast. In itself, wind energy is great – in suitable locations. But hardly to replace base load electricity supply. And while this is being applauded as an environmental victory, in perspective it is not: Japan is already admitting it will be 3% over its 1990 GHG emission levels, instead of 25% under, by 2020. All as most recent predictions about anthropogenic climate change indicate a bleak future for our oceans.

Sadly ironic, when all anyone’s worried about is releasing a heap of dilute contaminated water into the sea.

Pandora’s Promise

So I got to see Oliver Stone’s Pandora’s Promise

It looks great, and it lets the sober facts speak for themselves. I encourage you to see it.

An anti-nuclear environmentalist is featured briefly in it, and he took issue with some of the content

A really cynical mind might hear him rejecting the UNSCEAR and other agencies’ assessments of very few deaths directly caused by Chernobyl (instead insisting such mortality was in the thousands) and conclude he wants to believe more people died to bolster his anti-nuclear stance. I’m sure he’s not meaning to do that.

But his ilk need to understand and ultimately accept that this new generation of atomic proponents, as well as outspoken younger nuclear professionals is not going to go away, and will just keep educating the rest of us with the facts and benefits, the potential and promise.

The opponents will continue repeating their exaggerations and outdated misinformation. We’ll see how long they can keep that up.

 

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.