[unique_parrot2]

That's great. You know how expensive it is to get rid of radiactive material. It this comes true the big power plants can just dump the waste into the river and say "It wasn't me".

I would not want to live next to such a thing.

[musesum]

Here's one startup that is using a design that can convert spent fuel: http://www.transatomicpower.com/the-science/

Plenty of retiring Nuclear plants. Just do a conversion on the same real-estate and use the waste as fuel.

[EDIT] For a deep dive into Thorium, check out any one of the "Thorium Remix" vids: http://thoriumremix.com/2015/

[musesum]

Here's a list of other Gen IV reactor companies/projects (from Thorium Remix 2016):

Terrestrial Energy, Flibe Energy, Molten Energy, Transatomic, ThorCon Power, Copenhagen Atomics, Seaborg, Chinese Academy Of Sciences.

I uprooted unique_parrot2's comment, as it reflected my view about nuclear power, up until last year. Here is the documentary that changed my mind: http://pandoraspromise.com

[i_feel_great]

https://en.wikipedia.org/wiki/Deep_geological_repository

[einrealist]

And?

There is no repository in the world available, that is either guaranteed to be secure for thousands of years of accepted by the population.

Also putting it in the earth has one huge disadvantage: You cannot get it back if something goes wrong.

I can recommend this documentation about the waste disposal problem http://www.imdb.com/title/tt2979302/

[tremon]

There is no repository in the world available, that is either guaranteed to be secure for thousands of years of accepted by the population.

But we would have no need for "thousands of years" if the development of nuclear reactors is allowed to advance. Fast breeder reactors can use our current "waste" as fuel, leaving only stable and short-halflife isotopes as waste.

[kuschku]

Let’s look at the German Asse II and Schacht Konrad.

We deposited lots of nuclear waste, and years later discovered it was leaking into the tap water.

Now we have to dig it all back up.

[marak830]

Maybe someone here can inform me, howuch does the waste weigh? Would it be viable to launch it into space then send it on a course to the sun?

[shaqbert]

Amount of radioactive waste: A couple of tons every year per power plant is realistic.

Space dumping is a terrible idea. Expensive and risky.

Best storage solution so far found is what we've mostly been doing so far. Just having a sealed of area and store it for 20 or so years in a special low population and high security area that is protected from rain, frost, and temperature swings and have a good containment in case of container leaks. And then repackage in 20 years time for another 20 years. And so on. I.e. "actively managing" nuclear waste until the end of time.

Fun fact: The inner core of earth is not cooling mostly because of naturally occurring nuclear fission... so in a way our very own planet is full of radioactive waste already :)

[Gibbon1]

My observation that tends to annoy people is to point out that the best place to store spent nuclear fuel is inside the original fuel rods. The best place to store those is next to the nuclear reactor. The objection seems to center around reprocessing. Course the longer you wait before reprocessing the less radio isotopes you have to worry about.

[tremon]

I don't think anyone wants to take the risk of having the launch vessel explode while still in the atmosphere.

[marak830]

Heh you know I didn't even consider that factor.

[dsq]

Move fast and break things! ...maybe not...

[wiredfool]

It's easier/less deltaV to send things out of the solar system than it is to hit the sun.

(Basically, to hit the sun, you have to scrub out all/most of the velocity from the Earth's orbit, or what you've done is put your waste in an orbit around the Sun that may intersect the Earth's at some point in the future)

[TeMPOraL]

Technically you could try some clever gravity assists with Jupiter to greatly reduce the ∆v requirements. But that's still a very expensive way of solving a non-problem. We know how to deal with nuclear waste. The problem is with people being scared out of proportion by it.

[mac01021]

It isn't sufficient to launch in the general direction of the sun, using the minimum energy required to escape earth's gravity?

[Symmetry]

The reason the Earth doesn't fall into the sun is that it's moving quickly enough that the centripetal force balances the Sun's gravity. If you escape the Earth's gravity well and give it a small push it would still have nearly as much orbital energy as the Earth and way more than Venus, which hadn't fallen into the sun either.

To slow down enough that you could fall into the sun you need to kill 30 km/s of velocity. To go fast enough to escape the solar system you only need about 15 km/s. And crashing into Jupiter is even cheaper than that.

[cmrx64]

No. For an entertaining explanation why, see https://www.youtube.com/watch?v=uNS6VKNXY6s

[gus_massa]

Obligatory xkcd: https://xkcd.com/1244/ (explanation and more details https://explainxkcd.com/1244/ )

[mrfusion]

Why not do an elliptical orbit that takes you close enough to the sun to burn up? That seems like less energy than dropping to zero no?

[wiredfool]

You'd still need an Earth-Sun transfer orbit, which is still a lot of deltaV.

http://i.imgur.com/SqdzxzF.png

[lmm]

Close to the sun still takes more energy than leaving the solar system, similar to how it's just as hard to charge a capacitor to -9V as to 9V. And in what sense would it "burn up"?

[kazagistar]

Bring it up does not change the fact that there is now radioactive material on an orbit which still potential overlaps the earth. Out of the solar system is a much better solution.

[Symmetry]

On the other hand it's not like the Sun isn't spewing out way more radioactive material continuously than we're talking about adding here.

EDIT: To give some orders of magnitude, the back of the envelope tells me that the sun inflicts about 700 TBq of carbon-14 on us every year. For comparison, countries like the USSR and UK have dumped 85,000 TBq of radioactive waste into the ocean (and Fukushima added another 15,000). I don't know how to judge how much of the vaporized waste would end up back on Earth so it's quite possible I'm wrong in the above.

[adwn]

An elliptical orbit that gets close to the sun is nearly the same as an orbit that goes through the sun.

Besides, exposing radioactive materials to heat does not affect their radioactivity.

[msandford]

That's only true up to a point. I suspect that if you exposed just about anything to 100,000 kelvin it ceased to look like any kind of matter we know anything about.

[mikeash]

This experiment was performed thousands of times back in the 1950s and 1960s. A nuclear weapon's fireball is way hotter than 100,000K, and the exploding weapon contains lots of fissionable material and fission byproducts. The extreme temperatures don't destroy them, they just help spread it around.

[adwn]

> I suspect that if you exposed just about anything to 100,000 kelvin it ceased to look like any kind of matter we know anything about.

1e5 K? You're missing a couple orders of magnitude, there.

The hottest parts of the Sun's surface go up to 20 million Kelvin, and that doesn't "cease to look like any kind of matter we know anything about".

[outworlder]

TERRIBLY hard to send anything to the sun. Stuff does not just "falls" there, you have to cancel the enormous translation speed that the Earth has.

Plus, putting the stuff on top of a highly energetic vehicle is not the safest thing we can do with it.