In case there weren't enough energy worries...

[Terralthra]

Since when can nuclear power not be run at less than full-capacity? Control rods aren't just 100% in or 100% out. They can be inserted partially, moderating neutrons to a lesser or greater degree, which in turn moderates fission, which generates differing amounts of heat, and thus electricity. Who made up this "it's at 100% or it's off" nonsense?

[aerius]

Since when can nuclear power not be run at less than full-capacity? Control rods aren't just 100% in or 100% out. They can be inserted partially, moderating neutrons to a lesser or greater degree, which in turn moderates fission, which generates differing amounts of heat, and thus electricity. Who made up this "it's at 100% or it's off" nonsense?

The problem is when you do this it leads to uneven fuel burnup and possible instability and/or loss of efficiency in the reactor core. With conventional PWR and BWR you need to shutdown the entire reactor to refuel it & deal with the compromised fuel, this is an expensive pain in the ass which nuke operators don't want to deal with. CANDU plants don't have this problem since their design allows automated online refueling where any sub-par fuel bundles can be switched out without shutting down the reactor.

Now there is a way to get around this problem with nuke plants, you just need a properly designed steam bypass & cooling system where excess steam is routed past the turbines when full power isn't required. It will cause extra wear on the steam pipes & condensors and it'll cost more to build & maintain. Darlington NGS has such a system in place and it can load-follow, but for whatever reason it's not licensed to do so.

[Darth Tanner]

If your power storage infrastructure is robust enough and can hold sufficient energy

One of the reasons so many cables are being laid across european borders is to help with balancing so that excess generation can be spread about without the need to shut everything down. France has excellent cables to its neighbours because it needs them to offload its excess because it essentially has too much nuclear capacity that does not track demand very well or at all sometimes.

In terms of storage however there is no way to achieve any noticable amount of your base load in terms of pumped storage unless you have lots of mountain valleys you dont mind flooding or a few billion to throw at mining out a few mountains. It is vital however as its one of the only real ways to get instant energy onto the grid for balancing.

For a bit of information on the varience in the UK grid supply see National Grid

[Wing Commander MAD]

There's a question that's been bugging me regarding all the suggestings of "Green" energy sources over nuclear all these years. Aerius layed out the biggest issues with solar, but there is one other issue that I never see addressed no matter the source. What are the results of removing all this energy from natural systems on the environment itself both long and short term, without even considering issues raised by construction and maintenance? Particulary, I'm thinking on the scale to replace fossil fuel usage without using nuclear (or compartively very little nuclear like today). Hydroelectric generation, for example, while green has absolutely massive ecological impact. This is all far removed from areas I'm knowledgable about, though I know enough to know that energy is a conserved quantity.

[Sriad]

There's a question that's been bugging me regarding all the suggestings of "Green" energy sources over nuclear all these years. Aerius layed out the biggest issues with solar, but there is one other issue that I never see addressed no matter the source. What are the results of removing all this energy from natural systems on the environment itself both long and short term, without even considering issues raised by construction and maintenance? Particulary, I'm thinking on the scale to replace fossil fuel usage without using nuclear (or compartively very little nuclear like today). Hydroelectric generation, for example, while green has absolutely massive ecological impact. This is all far removed from areas I'm knowledgable about, though I know enough to know that energy is a conserved quantity.

A few studies (which regretfully I don't know where to find) have noted localized climate alteration from wind farms. Solar power isn't a major concern; you just won't get grass (or whatever) growing where you put the plant. Anyway, there ARE people paying attention to that sort of thing.

[Wing Commander MAD]

There's a question that's been bugging me regarding all the suggestings of "Green" energy sources over nuclear all these years. Aerius layed out the biggest issues with solar, but there is one other issue that I never see addressed no matter the source. What are the results of removing all this energy from natural systems on the environment itself both long and short term, without even considering issues raised by construction and maintenance? Particulary, I'm thinking on the scale to replace fossil fuel usage without using nuclear (or compartively very little nuclear like today). Hydroelectric generation, for example, while green has absolutely massive ecological impact. This is all far removed from areas I'm knowledgable about, though I know enough to know that energy is a conserved quantity.

A few studies (which regretfully I don't know where to find) have noted localized climate alteration from wind farms. Solar power isn't a major concern; you just won't get grass (or whatever) growing where you put the plant. Anyway, there ARE people paying attention to that sort of thing.

I was more thinking along the lines temperature with the ground heating and cooling with regard to large solar farms.

[Simon_Jester]

That's actually not so much the problem- it's cost of manufacture, heavy-metal mining and processing, things like that.