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Comment by pwhelan | Hacker News Reader

That is because of the fuel types used. The Navy is using cheap fuel from the weapons program, which provides more than enough power and fuel for their needs. However the cities would likely use a Thorium reactor, which can easily be made to not produce weaponizeable (sp?) byproducts. I refuse to believe that France can handle itself with fission plants and we cannot. We must not allow irrational fears to drive policy and we must stop the use of fossil fuels to provide the majority of our power.

I say gimmie a few hundred fission plants, a new electrical grid, and electric cars & trucks. Our greenhouse gas emissions will go way down and our geo-political strength will rise.

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Oh, and it would provide a spark for nuclear studies in the US which could give us an edge in energy production. I would love if the wind would provide for all our power needs, but fission is a great transition method. Use it until we can get fusion or viable solar/wind/bio power.

There's a good argument out there that wind can be considerably less expensive than coal with good energy storage and good transmission.

http://www.stanford.edu/group/efmh/jacobson/energy.pdf

I haven't seen anything like that for nuclear.

I wholly agree that, where feasible, wind and other renewable energy sources can and should be employed in preference to non-renewable sources. That said, as far as I understand, there are cases where such renewable energy sources are not feasible solutions, and in those cases, I think that we should prefer nuclear power to coal, diesel or any other fossil fuel power.

I can think of only four: naval craft, spacecraft, remote locations (e.g. antarctic) and when you need a neutron flux for some reason.

What are the others?

(This is intermittent renewables, wind+solar, with inexpensive and efficient energy storage. I agree if you don't have energy storage you're capacity limited.)

I was actually thinking of cases in which storage is limited, or in places where, for instance, that tend to get less wind. As for the energy storage issue, while storage technology has gotten much, much better, I don't think we're yet where we need to be to completely move over to pure renewable. I admit, though, that I am not an expert in energy storage, so I could be totally off on this.

All else aside though, wherever there is a choice between technologies such as coal and technologies such as nuclear energy, I think that the latter needs to be very seriously considered.

I'd like to point out that cheap energy storage actually improves the economics of nuclear power, by leveling the power demand, so they can productively produce power all the time, and hopefully replace natural gas for peak power.

Absolutely. However, storage helps intermittent and unpredictable variation more.

Energy storage isn't currently viable economically, but, speaking as the cofounder of a startup in energy storage, soon will be :-p

Well, there are problems with only relying on renewable power sources. Weather patterns change. At a glance, it would make sense to build smart a nuclear grid, then integrate distributed renewable power and storage options as appropriate. That gives the grid excellent redundancy and starts working on the current problems immediately while providing breathing room for the renewables.

The nuclear plants could then be used as backups and power government supercomputers when not needed (or something).

In the US, nuclear power is already cheaper than coal because we get most of it from old plants that have already paid for their construction costs, so now we're just paying operating and maintenance costs. Now imagine how much the situation would improve with any of these way of decreasing nuclear costs (in order of increasing radicalness):

* Mass-production of modular conventional reactors, like China is gearing up to do with AP1000 plants.

* Mass-production of smaller fourth-generation reactors, such as pebble beds (again, China is doing this) or some of the various breeder reactors, like the Hyperion Power Module.

* The same as above, but with Brayton-cycle gas turbines instead of steam turbines. This leads to simplified reactors and higher thermodynamic efficiency and quite significantly lower costs.

* The same as above, and then you stick them on a boat. This lets you float them to wherever they're needed, and the sea-water handles their cooling needs without costly cooling towers, and they can provide water desalination with waste heat. A nuclear aircraft carrier is already providing large amounts of fresh water to Haiti, and other countries are having serious water problems, and would pay good money for this. More here:

http://finger-tree.blogspot.com/2009/11/floating-nuclear-pla...

* Liquid fluoride thorium reactors. I love LFTRs; they're so damn beautiful that I'd recommend having a look at them just to appreciate the cleverness. They can be made at any size, they're self-regulating, they can load-follow beautifully, they can use supercritical CO2 turbines for cooling, the waste is tiny and becomes safe after about 500 years, and the fuel supply is enormous.

But how do the costs of any of the above compare to the cost of building a wind turbine? Even taking the fuel and operations and maintenance cost to be free, how does one compare the capital cost against other renewables where you don't pay for fuel?

If you use a Brayton-cycle gas turbine for a nuclear reactor, for example, now heat exchange to the gas becomes the biggest issue. And even the most optimized gas peaker turbine plants cost $500/kw.

The capital costs per kilowatt of average power generation are surprisingly good for nuclear. I don't have time to look up the figures now (sorry) but last time I checked, wind was more expensive to build average capacity than nuclear, even when you compared the cost of just the wind turbines with the complete cost of nuke plants.

> If you use a Brayton-cycle gas turbine for a nuclear reactor, for example, now heat exchange to the gas becomes the biggest issue. And even the most optimized gas peaker turbine plants cost $500/kw.

Heat exchange to the gas is an issue, but it's the sort of issue that nuclear reactor designers have a lot of experience solving. The Chinese pebble bed reactors, for example, are cooled with helium gas, and they don't seem to have much trouble with that.

As for the cost of the turbines themselves, in general Brayton-cycle gas turbines are cheaper than steam turbines, and supercritical CO2 gas turbines are remarkably small, so they'll probably be cheaper than the conventional ones. Even conventional gas turbines would work, though.

Of course, when competing with natural gas burners, the fuel cost is a huge issue. Natural gas fuel costs are vastly higher than those of nuclear plants (per kilowatt-hour, of course).

I'm not sure I answered what you were saying, but I hope I covered something interesting.

Prof. Marc Jacobson of Stanford pegs the cost of wind power at an amortized cost of wind at 3 - 4 cents per kwhr. There are independent indications that they're around 3.5 - 4 cents per kwhr. Nuclear can compete with that? Last I checked it was around 12 - 20 cents per kwhr...

http://www.stanford.edu/group/efmh/jacobson/energy.pdf

And, on the side, how about a Manhattan-style project to produce a commerical scale Thorium Reactor within five years?

Oak Ridge had a thorium reactor running for 5 years in the 1960's. I think it would be very feasible, especially since Canada is helping China with nuclear power plants. Thorium is also enormously more abundant and more evenly spread out over the world.

My point is that there's quite enough work already for such a corps. Weaponizeable (also sp?) or not, the idea of producing waste of such longevity and claiming that it is actually a solution is mind-bogglingly arrogant.

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