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Nuclear Power in the UK

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mikey9

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Please keep this going folks - I for one am fascinated (Father in Law did major Civils on Heysham back in the 60's) and love some facts, research and analysis.
The Drone footage of the Hinkley construction site is great stuff - I had no idea of the work so far.....and that all that progress appears to just be a scratch of the surface! Amazing.
 
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Kingspanner

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Talking generally about nuclear stuff
https://ratical.org/radiation/KillingOurOwn/ This link leads to an online version of an interesting book from 1982, setting out the case against nuclear power (and weapons) in the United States. Eye-witness accounts from those who suffered from atom bomb tests in the 50s and much more.

https://factsheets.inl.gov/SitePages/Publications.aspx Includes a link to an extraordinary book called "Proving the Principle" which is an insiders look at US military nuclear power development. Chapter 15, about the SL-1 reactor accident is a terrific read.

Many of us would like fusion, will we see it in our lifetimes? No.
(My apologies to those who don't want facts and science to get in the way....)
 

dgl

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Of course atom bombs and nuclear reactors are two completely different things, remember there has been no nuclear explosion from a power reactor and there never could be. All explosions involving Nuclear Power have been of the hydrogen variety.
 

HSTEd

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Of course atom bombs and nuclear reactors are two completely different things, remember there has been no nuclear explosion from a power reactor and there never could be. All explosions involving Nuclear Power have been of the hydrogen variety.
Chernobyl was a reactivity excursion accident that could be considered to be a nuclear explosion.
The react went prompt critical and up it went.
 

dgl

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Chernobyl was a reactivity excursion accident that could be considered to be a nuclear explosion.
The react went prompt critical and up it went.
But the actual explosion was a steam explosion due to vaporised superheated cooling water as a result of the runaway nuclear chain reaction. The primary nuclear material release was due to the subsequent reactor fire.
 

HSTEd

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But the actual explosion was a steam explosion due to vaporised superheated cooling water as a result of the runaway nuclear chain reaction. The primary nuclear material release was due to the subsequent reactor fire.
The explosion was caused the fuel generating an enormous heat spike that blew all the fuel pins apart and boiled the water around them.

The reactor operated in a mode characterised by geometrically increasing fission power terminated by disassembly

That meets the definition of a bomb
 

HSTEd

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It was a bomb, but it was a steam bomb. The primary shockwave was caused by a steam explosion, not the thermal nuclear reaction.
I mean it neutronically meets the definition of an atomic explosion.
This is like saying that the nuclear bomb is not an nuclear explosion because most of the mass of the plasma created was actually the ionised explosive lens and other bomb components.

EDIT:

The line between "nuclear explosion" and "non nuclear explosion in nuclear reactor" is often rather blurred, as in this case.
 
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Jozhua

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Nuclear power stations run at far too low concentrations of uranium to go critical.

It's expensive to refine nuclear materials, so the economics dictates power stations essentially have to operate in what happens to be the safest way.

Chynobl was a poorly designed reactor, operated somewhat incompetently. Standard have improved in the 50 years since it was built! Imagine a car of the same age, the safety standards are vastly different.

Ultimately, nuclear is a lesser of two evils. The only other realistic way of getting stable, reliable power is fossil fuels. However, global warming and pollution that probably kills more every year than nuclear has in it's whole existence is a massive issue.

It's like flying vs driving, people are more afraid of flying despite the statistics proving otherwise.
 

HSTEd

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Nuclear power stations run at far too low concentrations of uranium to go critical.
If that were true, the reactors wouldn't be generating any power at all!

Normally we try to operate reactors such that they are only critical using delayed neutrons produced by decaying fission products, as well as the "prompt" neutrons.

But it is entirely possible to mishandle a reactor such that it goes prompt critical, and then a (potentially very largE) power excursion will occur.
Chernobyl was a very unstable design with regards to power excursions from the low power regime, but the excursion could still cause extensive core damage in a modern reactor.
 

Jozhua

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If that were true, the reactors wouldn't be generating any power at all!

Normally we try to operate reactors such that they are only critical using delayed neutrons produced by decaying fission products, as well as the "prompt" neutrons.

But it is entirely possible to mishandle a reactor such that it goes prompt critical, and then a (potentially very largE) power excursion will occur.
Chernobyl was a very unstable design with regards to power excursions from the low power regime, but the excursion could still cause extensive core damage in a modern reactor.

Ahh, okay!

Still, the concentrations are much lower than those found in nuclear weapons, so it's not going to turn into a mushroom cloud anytime soon!

Do you do much related to nuclear power out of interest, or are you just a bit of a nerd like me? ;):lol:
 

HSTEd

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Do you do much related to nuclear power out of interest, or are you just a bit of a nerd like me? ;):lol:

PhD (student) in the use of nuclear power to combat climate change in the UK context, and a masters degree in nuclear science and technology, on top of a bachelors in chemistry and an integrated undergraduate masters in physics.

So a little bit, but ive been interested in nuclear power since long before I took up the masters.
 
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Cowley

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PhD in the use of nuclear power to combat climate change in the UK context, and a masters degree in nuclear science and technology, on top of a bachelors in chemistry and an integrated undergraduate masters in physics.

So a little bit, but ive been interested in nuclear power since long before I took up the masters.
As answers go that’s a pretty good one...
 

Jozhua

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PhD (student) in the use of nuclear power to combat climate change in the UK context, and a masters degree in nuclear science and technology, on top of a bachelors in chemistry and an integrated undergraduate masters in physics.

So a little bit, but ive been interested in nuclear power since long before I took up the masters.

Oh cool, sorry I don't always read through all the posts on a thread properly before saying things :lol:...

Considering what you've said about the issues with Hinckley Point C, is there a way we could build nuclear cheaper?

Maybe it would be good to have a UK design that is used for several new sites across the country. Then they can be built by the same teams and share parts/labour.

Also, I wonder what can be done about public relations. Most members of the public are still under the impression that renewables can actually offer a viable alternative to our current energy mix. Unfortunately though they aren't reliable enough, so end up with coal/gas coming online to fill in the mix. Power storage just isn't really there, unless we put considerable effort into building pump storage. Also, in colder climates like ours, solar basically generates electricity at the exact opposite times when people need it. Generates during the day, when people don't need lights on and is most effective in summer, when people need the least heating...

Many have come to the conclusion that nuclear is the very least the lesser of two evils, and if we want to have a chance of solving climate change, we have to take some difficult to swallow pills, one of which is that nuclear power may be our only reasonable source of clean energy.
 

433N

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Most members of the public are still under the impression that renewables can actually offer a viable alternative to our current energy mix. Unfortunately though they aren't reliable enough, so end up with coal/gas coming online to fill in the mix. Power storage just isn't really there, unless we put considerable effort into building pump storage. Also, in colder climates like ours, solar basically generates electricity at the exact opposite times when people need it. Generates during the day, when people don't need lights on and is most effective in summer, when people need the least heating...

The economics have changed markedly in recent years, to the point that renewables are way cheaper than nuclear. Whilst nuclear is filling a hole needed for security of supply, you have touched on the issue of storage - a step change there may well obviate the need for any nuclear. A further point that you haven't raised is importing energy from renewable sources. I believe that National Grid are currently commissioning a sixth (I think) switch input for continental energy which connects to the largest hydro-electric power station in the world in Norway (I don't know why we have never committed more to hydro-electric ourselves). Increased capacity from a number of these sources (and tidal) could well offer a viable alternative to nuclear in the medium term and make Hinkley Point look like an expensive white elephant.

It may also be the case that a more efficient distribution system could help since we currently have a system designed around large sources of electricity generation rather than a system designed around smaller generation schemes which are more efficient for distribution of renewable energy.
 

najaB

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The economics have changed markedly in recent years, to the point that renewables are way cheaper than nuclear.
They can be. But only because we do nuclear the expensive way. Small units (tens to low hundreds of MWe), of a modular mass-producable design is a much cheaper way to go. They wouldn't need the massive protection structures which are a huge proportion of the costs either.
 

HSTEd

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Considering what you've said about the issues with Hinckley Point C, is there a way we could build nuclear cheaper?
We stop believing spurious levelised cost of energy calculations for LWRs and build whatever design appears to be most "constructible".
Nuclear operating costs are so low that increasing them by a few percent by tolerating a 'cruder' but simpler to build plant design is a good idea in the current environment.

Also realistically - get the man from the Treasury to write us a cheque.
If the state built a nuclear plant using the rates offered by the Public Works Loan Board, let alone what the Treasury actually pays to borrow, nuclear becomes the cheapest form of energy possible, possibly excluding tidal barrages.
(In this scenario you want the lowest possible O&M costs, which excludes offshore wind
Maybe it would be good to have a UK design that is used for several new sites across the country. Then they can be built by the same teams and share parts/labour.
I'm afraid we used to own the AP1000 before Westinghouse got sold by BNFL (to Toshiba).
Also thanks to Clegg we are in no position to manufacture reactor pressure vessels in this country, he having cancelled the loan guarantee for Sheffield Forgemasters to build an ultra large forging press in 2010.

Also, I wonder what can be done about public relations. Most members of the public are still under the impression that renewables can actually offer a viable alternative to our current energy mix. Unfortunately though they aren't reliable enough, so end up with coal/gas coming online to fill in the mix. Power storage just isn't really there, unless we put considerable effort into building pump storage. Also, in colder climates like ours, solar basically generates electricity at the exact opposite times when people need it. Generates during the day, when people don't need lights on and is most effective in summer, when people need the least heating...
Oh it is possible in an engineering sense, but it will either be hilariously expensive or require the conversion of most of the Scottish Highlands and Mid Wales into lakes for pumped storage plants.

They can be. But only because we do nuclear the expensive way. Small units (tens to low hundreds of MWe), of a modular mass-producable design is a much cheaper way to go. They wouldn't need the massive protection structures which are a huge proportion of the costs either.
It really isn't.
SMRs are a desperate attempt to force nuclear into the Thatcherite electricity business model for which is it entirely unsuited.
The economies of scale from medium and large units are hilariously enormous, which is why the "SMR" concepts have been creeping up in size for years, to the point where the Rolls Royce design is the size of a late Magnox unit and approaching the size of the Dungeness B AGR!

The answer is probably however a massive build programme using a design optimised for easiest constructibility.
My own PhD baseline assumption is currently one gigawatt scale unit per month (just the UK), as that is the scale necessary to actually make a difference to climate change in the time allowed.

Also I wish you good luck convincing the regulator that you do not require a shield building on your reactor.........
You will need it.
 

Meerkat

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which connects to the largest hydro-electric power station in the world in Norway (I don't know why we have never committed more to hydro-electric ourselves)

because Norway has loads of sites miles from people.
We don’t have that many, so they are more valued for their scenic/environmental benefits and opposition is high.
 

najaB

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Also I wish you good luck convincing the regulator that you do not require a shield building on your reactor.........
You will need it.
I didn't say you don't need shielding. I said you don't need the massive pressure vessels that come with gigawatt plants. Smaller amounts of fissile material and lower pressures means smaller possible "boom" if things go wrong.
 

JamesT

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I didn't say you don't need shielding. I said you don't need the massive pressure vessels that come with gigawatt plants. Smaller amounts of fissile material and lower pressures means smaller possible "boom" if things go wrong.

Isn't most of the massive protection on new plants to mitigate the risk of a terrorist incident including a plane crashing into it? That's still going to need the same kind of shielding to prevent, even if the risk from the inside is much lower.
 

cactustwirly

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PhD (student) in the use of nuclear power to combat climate change in the UK context, and a masters degree in nuclear science and technology, on top of a bachelors in chemistry and an integrated undergraduate masters in physics.

So a little bit, but ive been interested in nuclear power since long before I took up the masters.

Sorry but that doesn't quite add up, so you did an integrated masters in Physics, but a bachelor's in Chemistry, how does that work?
But then another Masters in Nuclear science?
Surely you'd just do a BSc and straight into a PhD? :lol:
 

HSTEd

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Sorry but that doesn't quite add up, so you did an integrated masters in Physics, but a bachelor's in Chemistry, how does that work?
But then another Masters in Nuclear science?
Surely you'd just do a BSc and straight into a PhD? :lol:

I've been at university continuously since 2008.

Chemistry degree went badly due to smoe personal issues that meant I had to repeat a year - and statistically I was lucky to graduate at all. Got a very low 2.2
So did a five-year integrated Masters in Physics (Foundation Year + 3 year BSc + MPhys).
Did much better but again got a 2.2, but this time the highest possible 2.2!

But was accepted onto the Nuclear MSc because its a field that people aren't partiicularly interested in.
After I got a high Merit in that (failed one unit taught by a really really boring lecturer and didn't want to do it again so got no Distinction) I was accepted onto the PhD.

Long road to here, and av ery expensive one at that.

I didn't say you don't need shielding. I said you don't need the massive pressure vessels that come with gigawatt plants. Smaller amounts of fissile material and lower pressures means smaller possible "boom" if things go wrong.
The primary constraint on secondary containment systems (ie the building) is they have to be able to resist impact by a large commercial airliner being dived into them. (This is what a 'shield' building is in this context, it shields the reactor containment from outside damage)
As to the main reactor pressure vessel, on some of these new SMRs they are just as big as the gigawatt scale plants, they just pack more stuff in by having integral steam generation.
 

TrafficEng

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The economics have changed markedly in recent years, to the point that renewables are way cheaper than nuclear. Whilst nuclear is filling a hole needed for security of supply, you have touched on the issue of storage - a step change there may well obviate the need for any nuclear.

Batteries and pumped storage have a finite capacity and need to be filled first. If we had a prolonged period without significant renewable generation then we would need some nuclear as a backup. Gas/Diesel could be an alternative for that backup, but if we are aiming for zero carbon we'd only use it when essential and otherwise have it standing around doing nothing. Nuclear can do the backup, and sit there churning out zero-CO2 electricity day-to-day.

A further point that you haven't raised is importing energy from renewable sources.

There would be quite a lot of competition from other countries for those renewable sources.

...which connects to the largest hydro-electric power station in the world in Norway (I don't know why we have never committed more to hydro-electric ourselves).

We do have quite a lot of hydro (in Scotland) and most of the easily exploitable resource has already been exploited. There is scope for more smaller scale and micro generation, but costs increase. Norway's hydro-electric station isn't the largest just to get into the record books.

We have problems flooding valleys even to supply essential water to people, flooding them to generate electricity is low on the priority list.

It may also be the case that a more efficient distribution system could help since we currently have a system designed around large sources of electricity generation rather than a system designed around smaller generation schemes which are more efficient for distribution of renewable energy.

Genuinely interested to know what efficiencies you think are necessary? The shape of the system needs to be adapted to reflect changes in supply and demand (away from coalfields and industrial areas) but that work has been ongoing for a long time. And some forms of renewables (e.g. offshore wind) arrive at a point and act like a large generator, so they need the grid system to move that energy elsewhere. There is a lot of work going on in East Anglia at the moment to connect offshore wind capacity to the supergrid.

The grid is also needed for resilience and balancing supply/demand - for example if wind conditions cut production in one part of the country then it will need to import from elsewhere. Unless they have some handy local nuclear power stations that is. ;)
 

najaB

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The primary constraint on secondary containment systems (ie the building) is they have to be able to resist impact by a large commercial airliner being dived into them. (This is what a 'shield' building is in this context, it shields the reactor containment from outside damage)
Again, smaller amounts of fissle materials makes them much less of a target. Many of the small reactors on the drawing boards are transportable on a couple of flatbed trucks and could be fully contained (including from external phyisical impact) in a building the size of which wouldn't be out of place on a typical industrial estate.
 

HSTEd

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Again, smaller amounts of fissle materials makes them much less of a target. Many of the small reactors on the drawing boards are transportable on a couple of flatbed trucks and could be fully contained (including from external phyisical impact) in a building the size of which wouldn't be out of place on a typical industrial estate.

The problem with such small reactors is that they make all the fixed costs extremely consequential.
The cost guarding them alone would be enormous per kilowatt, because they still contain enough radioactivity to cause serious damage in nefarious hands.
The radioactivity release from even a very small reactor would still easily be the worst nuclear accident in British history.

The only way to avoid that is to concentrate enormous numbers on a single site, at which point you might as well just build larger units instead.
 

Strathclyder

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Apologies for breaking up this discussion, but seeing as it was brought up earlier in the thread & it's somewhat relevent to the thread as a whole, I thought I'd drop these ultra-rare Chernobyl images in here. Might interest a few of you:
L6JJhuz.jpg

ChNPP Unit #4 reactor hall pre-26/04/1986 - Exact date unrecorded. The angle we're all so familar with, but in a condition we're so unfamilar with. To be entirely honest, out of all the pics of the plant during the immediate aftermath of the disaster, the clean-up & construction of the sarcophagus, this one actually unnerves me more than all of them combined.

6AYzfqM.jpg

ChNPP's Reactor #4 nearing completion - November 1983. The reactor achieved it's first criticality on the 26th of that month, it's first grid connection occuring later on 22nd December 1983. Commerical operation wouldn't commence until 26th March 1984 however. This means that it had a in-service life of 25 months (2 years and a month or: 761 days, 108 weeks, 18,264 hours (rounded down), whatever way you wanna measure it) obviously not counting scheduled shutdowns for maintenance etc. Crazy when you piece all that together that's how short-lived Reactor #4 really was.
 

trebor79

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Wouldn't it be simpler and cheaper to just build another fleet of an existing design? Like bills 4 or 5 more Sizewell B's?
Obviously update certain aspects of the design for modern standards where necessary. But that must surely be cheaper and less risky than building something totally new?
 
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