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[Virex]

I still hold hopes for [hot]fusion, it is inherently possible, but not soon. (as in the last 30 years it is still expected to become viable during the next 30 years .)

That criticism is a bit misleading to say the least, because the concept for ITER was concieved in 1986, but due to economical and political considerations, the projects funding throuhg the early '90 was less then desirable. And even then the reactor concept was ready in 201, but it took till 2006 to sort out everything for the location. Basicly, fusion's such a big operation that the normal political slowdowns are also amlified.

[Neonivek]

it can't meltdown unless somebody leans on the "ON" switch for a few hours

WE'RE DOOMED!

[Hungry]

Is reminded of Chernobyl, the reactor blew its nearly 2000 tonne reactor upside down...and is still dangerous today...and this is why toady is holding off on nuclear reactions...the dwarves would destroy themselves in the drop of a fell mood..."No, Urst, not the reactor!"....although seeing a plume of nuclear death would rock in-game.

[qwertyuiopas]

Actually, scientists have had working fusion reactors for quite a while now.
The issue is that none of them have managed to produce more energy than they require to contain the fusion.

I have read that there are two main methods being used, a doughnut suspended magnetically, and hundreds of lasers from all sides. I have also read that some small Canadian group is trying to make a fusion reactor based on pressure waves rather than lasers, since it would be much less expensive.

I did a little digging and found it on the internet.

[andrea]

fusion isn't nearly as dangerous or polluting as fission.

fusion produces He, the same used for baloons. no nuclear waste.
if i remember correctly, radiation should  be very low, if any ( alpha radiation doesn't matter, since our skin can easily block it)
and risk is much lower. if fission goes out of control, it keep going and make lots of radiation, polluting an awfully large area. fusion... well, at most reactor melts, but that is it. it won't keep going, it will stop the moment the reactor goes off.

so fission gets my "NO" vote, while fusion gets my "YES" vote.

also, uranium is fairly rare, while hydrogen for fusion can be taken by water. and you all know how much water we have.

[Il Palazzo]

Thought that I'd correct some things:

4. No pollution whatsoever, as helium-4 is not a greenhouse gas.

but the neutron emerging from the reaction is likely to activate(radiologically) the surrounding material. Over time the radioactivity would build up and the construction would have to be removed and stored in the same fashion as it is done with today's reactors' containments.(think radioactive concrete)
It's not really that scary though.

5. Highly economical. The only materials you need once the reactor is built are deuterium and tritum, both of which are easy to get one's hands on (the oceans are FULL of hydrogen)

but you still have to extract those isotopes from water, which does cost a bit. It's not nearly as expensive as digging up and processing uranium, but you can't just "get some water" to fuel your reactor.

6. The only radiation it produces is alpha radiation (which is, in actual fact, a helium-4 molecule moving at a high rate of speed) which is so weak it can be easily stopped by a piece of paper.

Alpha radiation is indeed the least penetrating of the three types of radiations resulting from nuclear reactions(alpha, beta, gamma), but it's also the most ionizing, should it find it's target(i.e. somebody gets exposed to it).
Fusion(of the Deuterium-Tritium kind) also produces a neutron, which, as mentioned before, can make other materials radioactive, or decay into proton, giving away a beta-radiation particle(positron) which then annihilates with an electron, producing gamma radiation.
All in all, it's not a completely clean reaction, but it's way cleaner than anything else we could possibly get energy from.

Helium-4 is just regular helium like you find in balloons and little kids suck to make their voices sound like mickey mouse.

Not neccessarily, helium 3 and helium 4 are both stable. However when travelling at high speeds it's known as alpha radiation.

It(he4) is called alpha radiation particle only when it's electron-free.

I seem to recall that the surface of the sun is theoretically hotter than the inside (inside photons cannot escape and are contained in atoms)...this may just apply to the upper layers though. Pressure is the key force at the core I guess, pressure ~ friction ~ heat.

IIRC, photons can escape from the star's core freely, as plasma does not absorb them. You need atoms(i.e.nucleus with electron(s) ) for that, which can exist only in the outer layers, due to lower pressure there.

if i remember correctly, radiation should  be very low, if any ( alpha radiation doesn't matter, since our skin can easily block it)

if your skin gets exposed to 1 rad(or Gray) of alpha radiation, it's 20 times as likely to suffer damage as if it was exposed to 1 rad of gamma radiation. So try not blocking alpha particles with your skin.
But then, nobody is going to build a reactor that would have "windows" for alpha particles to escape and irradiate the visiting children from a nearby school. Or are they?

[Hungry]

Fusion reactions are extremly degenerating on fusion reactors....unless you can make fusion in a perfect sub-molecular solid....fusion reactor up keep is not practicly cheap...

[bjlong]

The main problem with fusion is that it's not a chain reaction, so you need a high density of material at a high temperature to get fusion. Like most alternative fuels, we're still at the research phase. Fission, on the other hand, is readily available, and actually very safe in modern power plants. (Chernobyl was poorly built, poorly run, and poorly maintained. It was a disaster waiting to happen.) Most nuclear waste can be recycled, rather than storing it in barrels of sludge or what-have-you, making fission my method of choice for today, as long as we're able to recycle the waste.

[Areyar]

blocking alpha radiation with your skin is not too smart, however several feet of air can do the job as well.

You don't want to know how many fission reactors are run currently as badly as Chernobyl, also most reactors in service right now are getting pretty old.
Anyhow as with any disaster, thankfully many things need to go wrong at the same time for a meltdown. 

[bjlong]

Considerably less than the number of dams left in an even worse condition. (In the US, at least.) My money is on the dams killing more people.

Also, if congress would allocate money to these types of power plants, then we could tear them down and build new ones. Everyone wins.

[Areyar]

good point.
In the Smurfs it was also more often the dam breaking than one of 'builder's inventions destroying the village.

A dam is inherently more stable than a nuclear reactor though.
Dam stability depends on the ground and it's construction/decay, while a running reactor is never stable but always on a knife's edge and requires constant monitoring.
That said, there are a lot more dams and anyone breaking would cause alot of damage.
A lot easier to clean up though.

[Jetman123]

Actually, scientists have had working fusion reactors for quite a while now.
The issue is that none of them have managed to produce more energy than they require to contain the fusion.

I have read that there are two main methods being used, a doughnut suspended magnetically, and hundreds of lasers from all sides. I have also read that some small Canadian group is trying to make a fusion reactor based on pressure waves rather than lasers, since it would be much less expensive.

I did a little digging and found it on the internet.

Ya, I mentioned both. The magnetic confinement in a torus is the russian "Tokamak" design, whereas lasers are another possibility.

[Yanlin]

Thought that I'd correct some things:

4. No pollution whatsoever, as helium-4 is not a greenhouse gas.

but the neutron emerging from the reaction is likely to activate(radiologically) the surrounding material. Over time the radioactivity would build up and the construction would have to be removed and stored in the same fashion as it is done with today's reactors' containments.(think radioactive concrete)
It's not really that scary though.

5. Highly economical. The only materials you need once the reactor is built are deuterium and tritum, both of which are easy to get one's hands on (the oceans are FULL of hydrogen)

but you still have to extract those isotopes from water, which does cost a bit. It's not nearly as expensive as digging up and processing uranium, but you can't just "get some water" to fuel your reactor.

6. The only radiation it produces is alpha radiation (which is, in actual fact, a helium-4 molecule moving at a high rate of speed) which is so weak it can be easily stopped by a piece of paper.

Alpha radiation is indeed the least penetrating of the three types of radiations resulting from nuclear reactions(alpha, beta, gamma), but it's also the most ionizing, should it find it's target(i.e. somebody gets exposed to it).
Fusion(of the Deuterium-Tritium kind) also produces a neutron, which, as mentioned before, can make other materials radioactive, or decay into proton, giving away a beta-radiation particle(positron) which then annihilates with an electron, producing gamma radiation.
All in all, it's not a completely clean reaction, but it's way cleaner than anything else we could possibly get energy from.

Helium-4 is just regular helium like you find in balloons and little kids suck to make their voices sound like mickey mouse.

Not neccessarily, helium 3 and helium 4 are both stable. However when travelling at high speeds it's known as alpha radiation.

It(he4) is called alpha radiation particle only when it's electron-free.

I seem to recall that the surface of the sun is theoretically hotter than the inside (inside photons cannot escape and are contained in atoms)...this may just apply to the upper layers though. Pressure is the key force at the core I guess, pressure ~ friction ~ heat.

IIRC, photons can escape from the star's core freely, as plasma does not absorb them. You need atoms(i.e.nucleus with electron(s) ) for that, which can exist only in the outer layers, due to lower pressure there.

if i remember correctly, radiation should  be very low, if any ( alpha radiation doesn't matter, since our skin can easily block it)

if your skin gets exposed to 1 rad(or Gray) of alpha radiation, it's 20 times as likely to suffer damage as if it was exposed to 1 rad of gamma radiation. So try not blocking alpha particles with your skin.
But then, nobody is going to build a reactor that would have "windows" for alpha particles to escape and irradiate the visiting children from a nearby school. Or are they?

I like to imagine this is Il Palazzo.

[Virex]

How would one go about building a window that would let alpha radiation through? I sense a contradiction there...

What you're forgetting is that alpha radiation is still ionised helium, and the whole point of a tokamak is to keep ionised stuff flowing ina certain way. Over time they've got to drain the reactor of He-4 of course, but that can be done in a controled fashion and the alpha radiation can be de-ionised in a safe way. Ergo, no alpha radiation problem.

[Areyar]

@yanlin:

I can't remember whether the energy states agitation by photonic energy can be obtained by electronstripped atoms...IIRC this indeed required electrons to be 'boosted' to higher 'orbits'. Can remember even less about spinstates... quantum mechanics meh.
I do remember photons take longer to travel through plasma (at least at solar pressures)than any type of medium. It took a ridiculous amount of time from emission from fusion in the core to radiation from the corona I recall.

Oh yeah, energetic neutrons....what does that fall under? Delta radiation?