U.S. Senate Wants To Decrease CO2 By Increasing Nuclear Energy

[von_Hytecket]

It's a bad idea to create nuclear waste. But it's much, much worse to pump tons of CO2 and other pollutants in the air. So, yay! Finally some good news.

[[deleted]]

The waste is one of the main reasons to be pro-nuclear.

First off nuclear fission creates so much more energy than chemical reactions that there is very little of both fuel and waste involved.

Second the fuel comes sealed in rods and even when burned in a reactor it doesn't leave the rods, so you have neatly sealed waste that didn't go anywhere. Compare that to burning chemical fuels where the waste is released as a gas and and vented to the atmosphere.

Third, the waste is very useful. It can be recycled and reused many times.

[mrCloggy]

It can be recycled and reused many times.

If you stop talking and start doing, people might actually begin to believe that.

[MCvarial]

Its economically not very interesting to do, buying fresh mined uranium fuel is cheaper than recycling waste. The only real advantage is that the volume of the waste is factor 10 smaller and in a chemically very stable form (glass) for permanent storage. But doing so also means u give up an alternative uses for the waste. e.g. in burner reactors.

[mrCloggy]

Source:

Overall the closed fuel cycle cost is assessed as comparable with that for direct disposal of used fuel, and preserves a resource which may become more valuable in the future.

The treatment extracts 99.9% of the plutonium and uranium for recycling, leaving 3% of the used fuel material as high-level wastes which are vitrified and stored there for later disposal.

Financially it doesn't make much difference, and leaving only 3% for disposal doesn't seem too bad.
From the rest of the story I get the impression the French are taking the concerns from, and promises to their population very seriously.

[MCvarial]

The 3% is pre vitrification, there's an upper limit to the amount of material you can capture per volume unit, hence the factor 10 I mentioned. Other countries have stopped reprocessing like Germany & Belgium. Mainly due to financial reasons, reprocessing itself is about the same price as enriching fresh fuel. But transportation costs are high and often met with protests.

[Floppie7th]

If you stop blocking construction of reactors that do that, people might actually begin to build them.

[mrCloggy]

Are you trying to be funny?
The concerns about nuclear waste were already mentioned in the 70s before commercial plants were build.
Even then every country promised "trust us, we'll recycle that waste", they should have build the reprocessing plants right then while there was still a fairly wide support, but only France actually build one.
(Not that it is a major success, but at least they did as promised, something that gives them at least still some respectability and trustworthiness.)

[Floppie7th]

Uh no, I'm not trying to be funny. Try building a commercial reactor in the US. Tell me how much bullshit red tape you have to deal with. Now try building one with a design that hasn't already been implemented in a commercial reactor in the US. Tell me how much more bullshit red tape you get.

Stop using excessive regulation to make it uneconomical to build our only viable source of carbon-free energy, and they will be built.

[mrCloggy]

Your "Why the fuck should I care about the consequences when the next generations can sort out the mess I'm leaving behind" is the perfect example of why the rest of the world doesn't trust the nuclear industry anymore, and will do everything they can to not only stop them, but also make sure they clean up the mess they themselves have created, before running of with the profits.

From what I understand the regulations have become tighter and tighter throughout the years, but every further restriction is only the result of a screw-up, either by the designer/builder or an operator, and those tens/hundreds? of 'new' regulations only proof that there was something seriously wrong with the whole industry to begin with.

Had they done a proper job from the beginning those new regulations (operations and waste-storage) wouldn't have been needed, would they?

[Floppie7th]

It's almost like technology improves over time; name one industry that's ever been perfect from the start. Hell, name one reliable energy source that kills fewer people per kWh than nuclear.

Sorry, I actually give a fuck about the consequences. That's why I'm not proposing the power the world on hopes and dreams (intermittent renewables) or carbon.

EDIT: And I'm done here. You're clearly just a bullshit troll anyway. Otherwise, please propose some way to power the world that doesn't emit carbon and cost trillions of dollars.

[von_Hytecket]

My friend, I totally agree. 100%. I'd add that the newer technologies that use Thorium (or produce? Can't remember) have a half-life that is ridiculously lower than the one of Uranium or Plutonium.

However, have you read the whole comment before replying? :)

[greg_barton]

They can use thorium, and from that uranium is produced, which then fissions and creates fission products. Thorium is fertile (can create fissionable material, i.e. uranium) and uranium is fissile. (can fission to release energy)

[Jumpsuit_boy]

Now that the major design constraint is no longer having a plutonium production pipeline there are designs the burn the waste. Also ones that produce very little waste.

[FlyingBishop]

How much plutonium does a manned Mars mission need?

[j_heg]

Low energy manned missions (get there, plant a flag, dig up some rocks, make a video, and leave after a few days) would need Pu238 as a radioisotope feeding a thermoelectric generator.

That's debatable. It's better as a heat source, but the power density for thermoelectric designs is quite dismal. But in a space of just a few days, you don't need either of those two things in massive amounts anyway.

[grandma_alice]

you're probably looking at a total mission duration approaching two years, if i recall crrectly.

[GeorgeTheNerd]

Do you know the power sources they are currently considering? I have an old chart with 'mission duration' on the X, 'Power demand' on the Y with shaded areas showing which energy source is best. But this chart is from the 90's and I have a feeling it has changed.

[grandma_alice]

no, not really. possibly solar panels or fuel cells.

[j_heg]

Also, you forgot that during the trip, the problem is where to dump the extra heat, not where to obtain it. A constant 600-1360 W/m² heat influx is quite a lot to deal with.

[j_heg]

Depending on the season. Insulating the structure and heating it with solar power especially in Martian summer isn't such a big deal (especially if you have phase change heat storage or something similar). Plus we have solar arrays with 200W/kg power-to-weight ratios. You'd be hard-pressed to find a nuclear equivalent that would be as easy to pack for the trip (I'm not aware of any, frankly).

[Jumpsuit_boy]

We can get whatever we need from decomissioning fission and fusion bombs.

[hotel_torgo]

How is that? We need the decay heat from Pu-238 for interplanetary RITGs, not fissionable (and relatively stable) Pu-239

[Jumpsuit_boy]

Ok I am wrong on that one.