Here's a pic for the pro-nuclear to enjoy.

[British Red]

But in that respect Andy - the judgement - the nuclear industry has itself to blame. I recall - long before any of the three incidents - being told "nuclear power is inherently safe - it cannot possibly cause a radiation leak or explosion - it just can't happen". That was the line that was taken back then - it can't happen. Right up to the time when it happened.

I'm not "anti nuke" or "anti renewable" or "anti coal".

I personally think there is far too much bias in all the arguments. There are risks in all forms of electricity generation. They are not all directly comparable. But they are all very real - is the long term storage of nuclear waste more dangerous than the CO2 from coal which only has a 50 year atmospheric window? Is the risk of environmental damage from a dam break greater than the risk of a radiation leak? Do we actually care about energy independence? If fast-breeder plutonium producing reactors are no problem - why all the fuss over Iran having them?

We will almost certainly need to use all the means we can in coming years. For me, the whole thing is just woefully inefficient. Venting steam (heat)....really? Really...we produce electricity and have waste heat and trnasport electricity to...wait for it....create heat. Its crushingly inefficient and only happens that way because of the way we do things. CHP is far more logical.

Coming down and saying one form only....any form.... is the way forward is going to leave people sitting in the dark.


The sooner I get that wind turbine the better

 

[santaman2000]

Wouldn't a nuclear power plant be more of a target for a terroist attack than a dam ?

Maybe. Maybe not. The reactors are generally much more protected than the dams. All it would have taken for a terrorist to take down the Hoover dam would have ben something similar to the Oklahoma City bomber driving a rented truck across the dam. It's a bit more dificult now (post 9-11) because traffic has been diverted away from the dam But a boat could still easily do a suicide run from Lake Mead. And taking down the dam would kill thousands downstream as well as kill the power grid for millions and the water supply for a few hundred thousand. A fairly easy and tempting target.

 

[santaman2000]

...There are risks in all forms of electricity generation.

...If fast-breeder plutonium producing reactors are no problem - why all the fuss over Iran having them?...

LOL. Come to think of it there's risk in ELECTRICITY itself. Electrocutions, electrical fires, etc. As far as Iran having reactors, well we both know that know one really cares about the reactors themselves. The real fear is that their nuclear power program is a front for developin nuclear weapons. Whether it is or not isn't a topic for debate here though.

 

[blacktimberwolf]

Considering that most of the French nuclear stations are on the Cherbourg peninsula,

Most of them ?

http://fr.wikipedia.org/wiki/Liste_des_réacteurs_nucléaires_en_France

 

[wingstoo]

IIRC, Most nuclear incidents have resulted from "Human error" failure to do the right things at the right times, left critical equipment without maintenance checks.
The Japan failure was a result of a multitude of problems, the earthquake wasn't the only problem, the generators weren't the only problem etc etc.

The RAF tried and in some cases succeeded bombing the German Dams during WWII, it took a fair bit more than a lorry load of explosives to create the conditions that caused them to breach.

http://www.thedambusters.org.uk/

It would take a lot to damage some of the more modern dams, it took Barnes Wallace three years to plan and instigate the bombing of the German dams.

 

[Angus Og]

Wouldn't a nuclear power plant be more of a target for a terroist attack than a dam ?

No attack the National Grid that's the weakness its out of date by 50 odd years

 

[santaman2000]

IIRC, Most nuclear incidents have resulted from "Human error" failure to do the right things at the right times, left critical equipment without maintenance checks.
The Japan failure was a result of a multitude of problems, the earthquake wasn't the only problem, the generators weren't the only problem etc etc.

The RAF tried and in some cases succeeded bombing the German Dams during WWII, it took a fair bit more than a lorry load of explosives to create the conditions that caused them to breach.

http://www.thedambusters.org.uk/

It would take a lot to damage some of the more modern dams, it took Barnes Wallace three years to plan and instigate the bombing of the German dams.

True again. But the explosives they had available at the time weren't really comparable to the home made stuff that amatuers today have either. Nor was the bomb delivery by air comparable to what a small suicide boat near the base of a dam can do.

 

[santaman2000]

No attack the National Grid that's the weakness its out of date by 50 odd years

That's my point for targets over here. I really don't know enough to comment on the UK but I would assume it's similar.

That said, Red and Toddy's comments regarding small power turbines on individual homes would (or at least SHOULD) certainly lessen any effects caused by reliance on a central grid system.

 

[wingstoo]

An attack on the electrical grid would most likely only cause local damage, which is usually easily circumvented, after all, it is a grid, cut one wire and they feed in through another one.

A small boat, might get through, but that might be an interesting challenge, after all the Dams in Germany had nets to stop attacks by boats, and it took a bouncing bomb to jump those nets, and the boat would also need to sink to the correct depth to have maximum effect, it took several attempts at each dam to get the desired effect,

 

[santaman2000]

An attack on the electrical grid would most likely only cause local damage, which is usually easily circumvented, after all, it is a grid, cut one wire and they feed in through another one.

A small boat, might get through, but that might be an interesting challenge, after all the Dams in Germany had nets to stop attacks by boats, and it took a bouncing bomb to jump those nets, and the boat would also need to sink to the correct depth to have maximum effect, it took several attempts at each dam to get the desired effect,

There's a key statement there, "had nets" how many of then have nets now? I know Hoover dam doesn't.

"Locally" you say. The grids are much more complicated than that. When Hoover dam was constructed the "local" population was minute and wasn't epected to really grow as it did. Almost ALL power produced there goes first to Southern California (Los Angeles) and then has to be bought back for Southern Navada and Arizona. Even if "locally were/is an apt term, the Los Angeles service area alone has a population of several million.

Also the fact that one grid feeds into another has proven to be more of a weakness here than a strength. It has caused the collapse of neighboring grids (in the Northeast US & Canada) when a simple cheap relay failed and the failure cascaded across 2 or more grids.

 

[Toddy]

I didn't know that Scotland was in a particularly favourable postion for renewable energies though
I just thought that the rest of the country hadn't gotten around to it yet

Either way, it appears that the environmental and floral and faunal impact is considered, and is actively mitigated where ever possible.
I can attest to the sudden surge of released waters though, I've kayaked on the Awe below Cruachan, and it can go from a total obstruction free run to everything from rapids, whirlpool and stoppers in short order :yikes: Fun though

http://www.snh.org.uk/publications/on-line/advisorynotes/37/37.htm

cheers,
Toddy

 

[blacktimberwolf]

True again. But the explosives they had available at the time weren't really comparable to the home made stuff that amatuers today have either. Nor was the bomb delivery by air comparable to what a small suicide boat near the base of a dam can do.

Dams are made from armored concrete tens of meters thick (at the bottom ) & capable of with standing thousands of tons of pressure per square meter, I think it would take more than a lorry or boat load of explosives to make even a dent let alone bring a dam down, even if they managed to make a crack there would be time to organise an evacuation further down river since they are constantly monitored for eventual breeches in the dam's structure...
I'm still convinced that a small Kamakarze terroist squad could do more damage attacking a nuclear plant than a dam...but then I suppose it all depends on the motives of the bad guys

 

[wingstoo]

There's a key statement there, "had nets" how many of then have nets now? I know Hoover dam doesn't.

I guess that they (TPTB) don't see it as a logical nor viable terrorist threat if that is the case, the Germans saw their dams as a viable and logical target so instigated what they felt were necessary precautions to try and stop such attacks.

"Locally" you say. The grids are much more complicated than that. When Hoover dam was constructed the "local" population was minute and wasn't epected to really grow as it did. Almost ALL power produced there goes first to Southern California (Los Angeles) and then has to be bought back for Southern Navada and Arizona. Even if "locally were/is an apt term, the Los Angeles service area alone has a population of several million.

Also the fact that one grid feeds into another has proven to be more of a weakness here than a strength. It has caused the collapse of neighboring grids (in the Northeast US & Canada) when a simple cheap relay failed and the failure cascaded across 2 or more grids.

But that wasn't caused by someone blowing a hole in the grid, take out a section of grid with a device that, for example destroys a sub-station or a few power pylons and I very much doubt that it will have the same effect.

 

[Angus Og]

An attack on the electrical grid would most likely only cause local damage, which is usually easily circumvented, after all, it is a grid, cut one wire and they feed in through another one.

A small boat, might get through, but that might be an interesting challenge, after all the Dams in Germany had nets to stop attacks by boats, and it took a bouncing bomb to jump those nets, and the boat would also need to sink to the correct depth to have maximum effect, it took several attempts at each dam to get the desired effect,

Maybe but I know people have worked in industry this for 25 years and its not the wire you cut, I'm not going into this in more depth

 

[Angus Og]

Some of the Hydro in Scotland make more from EU grants than selling electricity.

 

[Bushcraftsman]

I also think nuclear power is the way forward! however being a nuclear engineer I probably have a slight bias! It's true the vapours coming from any nuclear power station actually contain no radioactive elements at all. In fact the water that it originates from doesn't come into contact with anything radioactive.

Below is whats called a pressurised water reactor (PWR)

-Nuclear fuel in the reactor vessel is engaged in a fission chain reaction, which produces heat, heating the water in the primary coolant loop (red part) by thermal conduction. The hot primary coolant is pumped into a heat exchanger called the steam generator where it flows through hundreds or thousands of tubes (usually 1.9 cm in diameter). This coolant is pressurised to prevent it boiling.

-Heat is transferred through the walls of these tubes to the lower pressure secondary coolant located on the sheet side of the exchanger where it evaporates to pressurized steam. The transfer of heat is accomplished without mixing the two fluids, which is desirable since the primary coolant might become radioactive.

-In a nuclear power station, the pressurized steam is fed through a steam turbine which drives an electrical generator connected to the electric grid for distribution. After passing through the turbine the secondary coolant (water-steam mixture) is cooled down and condensed in a condenser. The condenser converts the steam to a liquid so that it can be pumped back into the steam generator, and maintains a vacuum at the turbine outlet so that the pressure drop across the turbine, and hence the energy extracted from the steam, is maximized. Before being fed into the steam generator, the condensed steam (referred to as feedwater) is sometimes preheated in order to minimize thermal shock

Hope this was found interesting to anyone, at least if you didn't know how it worked, you have a basic understanding now

Cheers[/FONT]

 

[Native Nathan]

when I worked for an Electrical Distributor (The companies the own the cables) there were some people with out mains power for weeks at a time..

 

[Native Nathan]

cheers for the explanation and diagram bushcraftsman

 

[joejoe]

probaly had this debate when went from coal to gas/ electric

 

[santaman2000]

Dams are made from armored concrete tens of meters thick (at the bottom ) & capable of with standing thousands of tons of pressure per square meter, I think it would take more than a lorry or boat load of explosives to make even a dent let alone bring a dam down, even if they managed to make a crack there would be time to organise an evacuation further down river since they are constantly monitored for eventual breeches in the dam's structure...

Actually no. All of them aren't made of concrete (although most of the ones with hydro turbines are) I know of several large reservoirs in Mississipi alone dammed with earthen dams (Lake Ross Barnet is one of them) And as for all those concrete ones that are "checked regularly" many (if not most) of them are now over 70 years old (some of them even older) and the engineering reports really ain't too promising.

Even the ones referenced in Germant during WWII were destroyed by relatively small amounts of explosive (by today's standards) once they were able to place it at or below water level (not really a difficult feat for a suicide bomber)