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Post by Ben E on May 6, 2012 20:47:20 GMT 9.5
Hi all, I've just read what for me is a new anti-nuclear argument - thought you might be interested, and able to tell me if it were true... www.elmundo.es/elmundo/2012/05/04/natura/1336123895.html (sorry, in Spanish) The last sentence of the article says: "The same [in Spain] as in Japan, the use of nuclear power plants requires that there be thermal fossil fueled backup (i.e. gas or coal) of a similar order to the amount of nuclear, in order to avoid sudden cuts to the supply [in the case of a NPP shutdown]" The thesis is that when a NPP stops, for whatever reason, there's an instantaneous drop of 1GW, say, which only fast-reacting fossil plants can respond to. Seems like nonsense to me, but perhaps they do run grids like this?
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Post by Barry Brook on May 6, 2012 21:00:38 GMT 9.5
Ben, this is no different to the situation with coal. The typical way to cope with this is for the electricity generation system to have a 'reserve margin' of additional plant (hydro, gas, or just other coal and nuclear), on the order of 20 to 25 % above the typical peak load. This is how Australia copes with 80% coal (and some very large plants), for instance, and how France copes with 80% nuclear.
The great thing about large-scale nuclear is that we don't need to guess how it's done. We can see it, operating in the real world, in France. It's something technosolar (non-hydro) renewables just can do, at present.
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Post by LancedDendrite on May 6, 2012 21:09:01 GMT 9.5
It's merely stating a fact: An electricity grid requires a spinning reserve of backup to fill in the 'gaps' when a generator goes down or electricity demand goes up.
It's not really an anti-nuclear argument. Why? Because it affects all types of baseload power generation (and renewables too, to an even greater extent). Nuclear power plants have the highest power generating uptime (otherwise known as capacity factor) of all types of generation, so it's less of a problem for them anyway. Nuclear plants generally have week-long shut downs for refuelling and routine maintenance that grid operators know about years in advance so that they can plan for them. Unforeseen outages are about as common or maybe even slightly less so than fossil-fuel generators.
All that argument is is that you will still want to have some fast-responding peaking power that you can utilise in those sort of contingency scenarios even if you go close to 100% nuclear.
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Post by anonposter on May 6, 2012 21:22:47 GMT 9.5
Hydro can do the job better than fossil fuels so if your grid has enough hydro you don't need fossil fuels (you might keep a few gas fired plants around for cases where you have a lot of nuclear plants off line, a drought and high demand).
Nuclear plants can load follow if needed (better than most fossil fuel burners, coal power plants are very slow to respond, simple cycle gas relatively quick) so 100% nuclear is possible if you're willing to have reactors not running at full power a lot (you can also with some design changes make reactors that can respond faster, naval reactors can change power levels very quickly).
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Post by Ben E on May 6, 2012 22:15:15 GMT 9.5
Thank you all ;D Logic said it had to be that way, but you never know...!
I think I see now where the journalistc confusion comes from; Spain gets 20-25% of it's electricity from nuclear - roughly the same as the reserve margin.
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