Nuclear Power

Everyone likes to argue the obvious point that alternative energy doesn’t get enough attention in the world today.

I’ve seen few decent discussions about the current state of nuclear power. From my understanding nuclear power still has considerable waste due to the required cooling apparatus. We haven’t been too keen on nuclear power since 3 mile island et al - so would I be right to assume that nuclear power technologies haven’t advanced much since then? I know the answer isn’t “wind and solar do nothing - lets go nuclear for everything” - and I’ve mostly been anti-nuclear power thus far.

Nuclear optimists and pessimists debate:

I figure wind and solar are fine on the small scale, but nuclear is simply too useful to be dismissed.

There have been huge advances since then. Pebble bed reactors, for instance, are inherently meltdown-proof: If they start to melt down, the reaction just plain stops, even without any sort of active control mechanism.

Nuclear power has advanced quite a lot since then.

Exactly zero people were killed by Three Mile Island. And they’re far safer now. All things considered, nuclear power’s probably one of the safest methods of power generation there is, and the fuel supply is effectively endless. The main obstacle is cost; the capital and running expenses are astronomical.

What about cooling? Are modern nuclear power plants really non-poluters? Solar power is criticized for the waste of solar cells and wind is criticized for its effect on very local environments.

One thing, though, is that wind and solar are distributable, while nuclear must be centralized. So we must account for the tremendous energy loss during transportation (power lines - and we are going to be running superconductors anytime soon).

What about cooling? A nuclear reactor heats water(which also cools the core), which then boils water in a seperate system(the two don’t actually mix) to make steam and turn power turbines. Energy lost is in the form of heat, particulary because nuclear plants tend to be closed systems as much as possible and reuse as much water as possible.

The nuclear reaction doesn’t pollute as long as contaminant is intact. Only steam is released to the outside environment normally. There is radiotive waste created, but that’s a disposal, rather then an air/water pollution issue(unless one were to be stupid and just dump it in the water).

Not true. Especially with the modular nature of pebble bed reactors, it would be possible to build them closer to site and tailor them to individual needs.

Well, this isn’t precisely true. You can’t, on a cost-effective basis, slap up a wind turbine just anywhere. Some places have a enough wind and some don’t.

And even if you could throw turbines up anywhere, evidence suggests people will fight them tooth and nail; NIMBY syndrome always seems to pop up where wind turbines are concerned.

Solar power is a bit easier to distribute, but the corresponding limitation is that it doesn’t produce a lot of power.

What “considerable waste” do you think is associated with the cooling apparatus?

Pressurized water reactors (the type by the U.S. Navy and in many [most?] commercial power plants) utilizes a primary coolant loop that transfers heat to a secondary loop, in which steam is produced which drives a turbine connected to an electrical generator. The substance used in both loops is water. The loops do not mix because the primary loop picks up trace amounts of radioactive material from pipes, valve seats, etc. Admiral Rickover, founder of the nuclear Navy, famously drank a glass of primary coolant in front of Congress.

Anyway, after the steam produced in the secondary loop is run through the turbines, it has to condensed back to water so it can be recirculated back into the steam generators. Heat is removed from the steam to accomplish this–this heat is transferred either to a natural body of water, or one of the iconic air cooling towers is used.

Under normal operations, the only waste product associated with the cooling apparatus is slightly warmer sea water or river water, or warm air coming off the top of the cooling tower. That’s it.

The waste products from the fission reaction are tightly contained in the reactor core, and only removed during refueling operations.

My main problem with nuclear isn’t with the technology, I’ve no doubt it’s advanced tremendously in the last 30 years. It’s with the construction techniques. I seem to recall (no cite, sorry), that some reactors were built with faulty welds, poor quality concrete, and in one case, if memory serves, a reactor that was installed backwards! (Marble Hill in Indiana had cost overruns and construction problems, and here’s a cite for that project:

The other problem I’ve always had may be solved by now, and that is what to do with the reactor when it comes time to decommission the plant. At some point, it’s going to come to an end of a useful life, and something will have to be done with the reactor, just as with spent fuel rods.

Solve those two problems (I’m aware they may be solved, and more than willing to be enlightened if they have), and I’m more willing to be onboard with nuclear plants.

Are you guys imlpying that nuclear power has fewer downsides than solar, wind, and tidal?

Are you guys implying that the fear of 3 mile island like senarious (that generated considerable amount of fallout which is nearly impossible to clean up) are irrational with our current improved nuclear power technologies?

So, I’ve been wrong in believing that nuclear power plants polute by using lake water for cooling?

Reactors have a life of 40 years. Then we have a radioactive sore while we build another one. They cost a fortune to build,take years to build and do not provide cheap energy. We do not know what to do with the waste. It is not a solution without serious problems.

It depends on what you define as “pollution.”

If a nuclear power plant uses lake water for cooling, what happens is that the lake water gets warmed up slightly. This is often referred to as “thermal pollution.”

While warmer water can have deleterious effects for organisms in the lake, the effect is generally localized (i.e. near the outlets). Once the water cools back down and mixes with the rest of the lake water, there is no permanent effect on the water. You obviously would like to have as large a water body as possible, however, to minimize the effects of thermal pollution.

For example, Naval reactors use ocean water. Oceans are big, and the heat added is minuscule in comparison. At sea, especially with the vessel constantly in motion, there is no measurable effect whatsoever due to this “thermal pollution.”

There is no reason why the site of a nuclear reactor could not be used for another reactor.

Nuclear power will eventually come into its own as fossil fuels get more scarce, and thus, more expensive. There are only so many suitable sites for solar, wind, and tidal power, and no way to supply all of our energy needs solely with these alternative energy sources.

You can say the same thing about fossil-fueled plants. Although because we do not know what to do with the waste, we simply spew it continuously into the environment. And how is that working out for us now, what with acid rain, heavy metal emissions, and global warming?

You are quite literally comparing apples and oranges. All energy sources have downsides.

I’d say that you are misinformed. What “considerable amounts of fallout” do you think were released by the 3 Mile Island accident? While some radioactive gases were released in the course of the cleanup, most were noble gases that dispersed naturally and do not concentrate in the environment. There is simply nothing to clean up.

Realize that there is a considerable amount of natural radioactivity in the environment anyway. Granite rock contains trace amounts of uranium. Radioactive radon gas is naturally produced in the ground. You are exposed to more radiation by natural sources than I think you realize.

As far as the effects of the accident on the polulace, see the wikipedia entry:

Is that argument that we can’t use enough of solar, wind, tidal, and geothermal to supply all of our energy needs - so the next best thing is to use nuclear?

I haven’t yet accepted the premis that solar, wind, tidal, and geothermal can’t be used everywhere very locally, partially locally, and ‘nationally’ to fulfill all energy requirements.

For example, solar panels on the roof of every building (residential and otherwise), windmills in the most convenient places in every city, tidal on all currently uninhabitable portions of the costline, and solar using mirrors in most of the sunniest deserts.

Just to throw out a few problems that occur to me off the cuff:

Solar power does not function at night or on cloudy days. In many parts of the country, you don’t get enough sunny days to make it cost effective to install.

How effective do you think wind turbines will be if you stick them all over the place, including less windy areas? What environmental effects are there from wind turbines? What is their effect on birds and bats?

How do you cost effectively transmit power from the coast to the interior for tidal power? What environmental effects are there from tidal generators?

Is geothermal practical everywhere? How much does it cost to install for what benefit?

So has anyone actually built a pebble bed reactor yet? Last time I looked into this (a couple years ago) none had been, and I’m kind of skeptical of claims made for a tech that hasn’t been put into production.

Yes, but we are going to have to get better at storing power sometime - the switch to electric cars will require batteries too. I know there are considerable estimates for how much sun solar power system will be missing out on, but it seems to be the best step away from “put crap loads of power in a central location and transport it via power lines.”

I don’t see why wind turbines couldn’t be strategically placed, but I don’t know enough about their environmental effects. I know that there are scaled down options for silence and scability.

Tidal power would fall under partailly local - where costline people would benefit.

I’m guessing you’ve seen the German scientist’s estimates of our abilities to power entire countries using the solar power from just a section of a sunny deset. I know this would innitially be expensive, but in the long run couldn’t it be more cost effecitve and technologically productive than building lots of nuclear power plants?

It could be, but I am not advocating eliminating any option. I think we are going to need a mix of technologies, and I expect that nuclear power will be one of the options we should explore along with other alternative energy sources such as solar, wind, etc.