"We can’t see inside Fukushima Daiichi because all our robots keep dying"

[james_s]

Depends on one's definition of cheap. My electricity is about 8.2c/kWh, IMO that's pretty cheap. Even if the energy source was free, there are still a lot of costs in building and maintaining the infrastructure. I'd be willing to pay more than I do already if it meant clean, environmentally safe power in quantities that could meet our demand and save fossil fuels for applications in which they are not so easily replaced. I don't think we're going to see electric jumbo jets any time soon. Even if you could make a battery that matched the energy density of kerosene, it's not going to get significantly lighter as the energy is consumed as occurs with liquid fuel.

[Alex Eisenhut]

Cant wait for cheap fusion power, though once we have it, I'm sure there will be reasons it wont be cheap for the regular end consumers...

Sure, we just need to exceed the conditions at the heart of a star by a few orders of magnitude and solve the vexing problems of neutron activation of the (non existent as yet) blanket material/structures to actually extract heat from the reaction. Because unlike Star Trek, fusion reactors will just be glorified steam turbines.

http://physics.ucsd.edu/do-the-math/2012/01/nuclear-fusion/

...but

www.generalfusion.com

Let's just say I'm not packing for my warp drive tour of the galaxy just yet.

[Assafl]

But we just cannot as a species deal with such long term risks - risks that extend far beyond the length of even the most long lasting of past human civilizations.

I think the fact that otherwise well informed, technically savvy members of this forum can say things like "spent fuel is not really a problem" demonstrates that.

I don't think that technical minded people who say "spent fuel is not really a problem" are asking to ignore long term risks. I think what they are reflecting on is that storing lots of potential energy - in whatever form it happens to be in - can be a poison pill.

First: lets get NIMBY out of the way - if a dam in California breaks - it is their problem. And sure, coal emissions only heat up the other side of the world and cause cancer to "those" people. And many agree fossil fuels seem limitless. But that is turning a blind eye - the risks and grave dangers inherent by ANY storage of potential energy are only ignored by the same types who live on the slopes of Mount Vesuvius and are afraid of pressure cookers. It is "those" people.

Get over it - potential energy is generally safe if it is 12V on a 100uF capacitor - Anything over that is asking for trouble and utterly dangerous.

And YES: Radiation is scary; Global warming is scary; Lead pollution is scary (any pollution is scary); Dams collapsing is scary; Flying turbine blades are scary (even if they are very high up and very big). Heck - even a hand-granade is scary (and that is some cockamamie potential energy in the form of piddling chemistry - not enough to kill a fly a 100 yards away...); I even get scared standing on the ledge of a cliff - potential energy is (and should be) scary.

The only thing substantially scarier than storing potential energy is NOT having it when we need it.

[wraper]

It has always seemed to me that if the spent fuel is that active still, there ought to be much more energy that can be extracted from it. Surely if it has to be actively cooled we can use that thermal energy for something useful?

That is unfeasible. It's much more effective to supply heat from nuclear power station, and this actually do happen, I've seen myself hot water pipes going from nuclear power plant to the nearby town. https://www.iaea.org/NuclearPower/NEA_Cogeneration/index.html