Hello, a discussion about memes and their influence on bunk.

[JRBids]

My Phd revolved around offshore windfarms. Many people think they are relatively benign to the environment but the reality is different. They have the potential to shift sediment and erosion, as well as affect currents in the right formation. Even small changes in the flora and fauna can affect migration and spawning patterns. At the end of the day all energy sources, even green energies, come at an environmental cost and we just have to weigh up which is the worse. Iceland is a poor model to use given that it has a population around 300,000 and it is easy to locate its centres near the sources.

Iceland also uses what it has locally available: geothermal energy. If I am not mistaken the houses on Iceland aren't even wood, because there was so little wood?

 

[David Fraser]

in your opinion, is nuclear a better option than wind, from an environmental perspective?

There is no simple answer to the question really and it does depend on what environmental perspective you look at. In terms of CO2 Payback they are both the same. Dependant on type of plant nuclear is around 10 months to 2 1/2 years, and depending on site a windfarm is 5 months to 3 years. However a windfarm has a much shorter lifespan with turbine efficiency decreasing by each year. Industry states around 20 years but after 10 or 12 they can be unviable to run. Wind does need a back up supply usually.in the form of gas generators. There are some ecological impacts that are coming to light and all very much dependant on location. Nuclear on the otherhand has a lifespan of around 40 years and a much higher and reliable output. However the main issue in the UK seems to be around the waste rather than safety. We are finding it difficult to locate a suitable storage location. One had been proposed in Cumbria but got knocked back. There were concerns about pollution and the local ecology but seeing as the area includes the Lake District, the land of Beatrix Potter I would have thought that having rabbits and frogs mutate and start walking upright and talking English could only be a good thing.

I am tempted to side with wind but I am a realist and as long as Joe Public does not change their behaviour nuclear is the only viable option.

 

[Grieves]

Me too and burning fossil fuels doesn't?

Fossil fuels put society at risk. Even if a poisonous level of carbon dioxide found its way into the atmosphere, the planet would recover, and relatively quickly, with us currently having the technology to survive such a thing. Most people don't think, to my knowledge, we're pumping enough carbon dioxide into the atmosphere to literally 'poison' it. The threat of global warming is one of adverse weather conditions (dangerous storm-systems, drought ect.) and wide-scale flooding. These are indeed serious issues, but they're also survivable issues. No aspect of global warming threatens life on the planet itself, to my knowledge. Nuclear weapons/Nuclear power does.

However the main issue in the UK seems to be around the waste rather than safety.

The waste material is going to keep piling up, and its going to be more and more difficult to find suitable places to bury it away in. The more of this stuff we bury away, the more likely it becomes that containment fails.. and though 'Murphy's law' isn't a scientific principal, it does tend to ring with some truth most of the time. Given the nature of radioactive waste, and our inability to predict the future anywhere near as far as the stuff will often remain dangerously radioactive, Nuclear power at the scale we utilize it today seems short-sighted even barring any accidents. Japan, an island nation without a lot of forest to speak of, is currently having to clear-cut in a rather desperate bid to find storage-space. It's a short-term example of the long-term problem of every nuclear power plant, even those at no measurable risk. All of them produce radioactive waste, all of them need to store it somewhere, and there's no 'good' place in which to store this stuff.

 

[Cairenn]

The best solution to the waste problem is to move to breeder reactors.

Waste reduction
Actinides Half-life Fission products
244Cm 241Puƒ 250Cf 227Ac№ 10–22 y medium m is
meta 85Kr 113mCd₡
232Uƒ 238Pu 243Cmƒ 29–90 y 137Cs 90Sr 151Sm₡ 121mSn
ƒ for
fissile 249Cfƒ 242mAmƒ 251Cfƒ[23] 140 y –
1.6 ky

No fission products
have a half-life in the
range of 91 y – 210 ky
241Am 226Ra№[24] 247Bk
240Pu 229Th 246Cm 243Am 5–7 ky
4n 245Cmƒ 250Cm 239Puƒ 8–24 ky
236Npƒ 233Uƒ 230Th№ 231Pa№ 32–160 ky
248Cm 4n+1 234U№ 211–348 ky 99Tc ₡ can capture 126Sn 79Se
236U 237Np 242Pu 247Cmƒ 0.37–23 My 135Cs₡ 93Zr 107Pd 129I long
244Pu № for
NORM 4n+2 4n+3 80 My 6-7% 4-5% 1.25% 0.1-1% <0.05%
232Th№ 238U№ 235Uƒ№ 0.7–14 Gy fission product yield[25]

Nuclear waste became a greater concern by the 1990s. Breeding fuel cycles attracted renewed interest because of their potential to reduce actinide wastes, particularly plutonium and minor actinides.[6] After the spent nuclear fuel has been removed from a light water reactor for longer than 100,000 years, these transuranics would be the main source of radioactivity. Eliminating them would eliminate much of the long-term radioactivity from the spent fuel.[7]

In principle, breeder fuel cycles can recycle and consume all actinides,[4] leaving only fission products. As the graphic in this section indicates, fission products have a peculiar 'gap' in their aggregate half-lives, such that no fission products have a half-life longer than 91 years and shorter than two hundred thousand years. As a result of this physical oddity, after several hundred years in storage the waste's radioactivity would drop to the low level of the long-lived fission products. However, this benefit requires highly efficient separation of transuranics from spent fuel. If the fuel reprocessing methods used leave a large fraction of the transuranics in its final waste stream, this advantage would be reduced.[3]

Both types of breeding cycles can reduce actinide wastes:

The fast breeder reactor's fast neutrons can fission actinide nuclei with even numbers of both protons and neutrons. Such nucleii usually lack the low-speed "thermal neutron" resonances of fissile fuels used in LWRs.[26]
The thorium fuel cycle inherently produces lower levels of heavy actinides. The fertile material in the thorium fuel cycle has an atomic weight of 232, while the fertile material in the uranium fuel cycle has an atomic weight of 238. That mass difference means that thorium-232 requires six more neutron capture events per nucleus before the transuranic elements can be produced. In addition to this simple mass difference, the reactor gets two chances to fission the nuclei as the mass increases: First as the effective fuel nuclei U233, and as it absorbs two more neutrons, again as the fuel nuclei U235.[27][28]

A reactor whose main purpose is to destroy actinides, rather than increasing fissile fuel stocks, is sometimes known as a burner reactor. Both breeding and burning depend on good neutron economy, and many designs can do either. Breeding designs surround the core by a breeding blanket of fertile material. Waste burners surround the core with non-fertile wastes to be destroyed. Some designs add neutron reflectors or absorbers.

The big problem with them is that bomb quality material can be generated. There are ways of reducing that.

 

[Jazzy]

The threat of global warming is one of adverse weather conditions (dangerous storm-systems, drought ect.) and wide-scale flooding. These are indeed serious issues, but they're also survivable issues.

They aren't issues you want to be confronted with, because, together with the declining availability of oil, they will reduce the production of food to about a tenth of its present value. Even the Black Death killed only 1 in 5. Surviving will be for the survivors. That may not be you. I shouldn't hold out much hope for that scenario. Macrosocial cohesion will not survive it.

Nuclear may well be necessary, but I hate it because I know how they are designed and maintained. Initially they are well designed and maintained. By the nature of the world, the clever engineers move on/die, leaving maintenance crews to be selected by accountants after a decade or two, and the original safety culture gets lost. Then it's just a matter of time before a disaster occurs.
It keeps happening because human beings are mostly crap. If they are accountants they are 100% crap, living off the switch on a microcircuit. Nobody should allow accountants anywhere near nuclear engineering, or anything practical, for that matter.

Dear reader, if you are an accountant - I don't care.

What about nice non-lethal thorium reactors?

 

[Jazzy]

the main issue in the UK seems to be around the waste rather than safety. We are finding it difficult to locate a suitable storage location. One had been proposed in Cumbria but got knocked back. There were concerns about pollution and the local ecology but seeing as the area includes the Lake District, the land of Beatrix Potter I would have thought that having rabbits and frogs mutate and start walking upright and talking English could only be a good thing.

They already have. Liberals and Tories. I (and very many others, some over me) designed Seascale's Decanning plant. When I lived in St. Asaph my family and I used to swim in the Irish Sea. Er.

nuclear is the only viable option.

Thorium works in specialized reactors. Its byproducts cannot be used for weapons. That's a viable option with a future. It still makes radioactive waste, though.

 

[Jimbo]

Have you been noticing those house-centipedes more often lately? If so it might be a conspiracy.

Looks like the word is out. Indeed, shape-shifting reptilian humanoids from the Alpha Draconis star system, now hiding in underground bases, the force behind a worldwide conspiracy against humanity, are running the Bilderbergs, the trilateral commission, and the Rothschilds, at a secret lab run by Monsanto and HP, to breed bio-engineered centipedes, that are being deployed worldwide, via chemtrails... for purposes only you can imagine. But certainly including sapping our precious bodily fluids.