Out of all major energy sources, nuclear is the safest • Hacker News Board

Re: Out of all major energy sources, nuclear is the safest

#481

Post by ianai » Mon, Jul 31, 2017, 7:56 PM UTC

Spooky23 wrote: post #432

payne92 wrote: post #13

I believe the politicization of nuclear energy (the resulting lack of investment & innovation) will go down as one of the major blunders in human history. We'd be in a far, far better situation with greenhouse gasses if we (as a human race) had continued to invest in nuclear energy. There would have been mishaps along the way, but at a much smaller scale than we're experiencing now with deaths from air pollution and…

We would be in a better place with respect to greenhouse gasses. But we're also subject to long term disposal of waste products and high risk of pollution of groundwater, and other water sources. Some of those risks will be risks for thousands of years. The typical answers from nuclear proponents never cover what to do with the waste product.

You send it to Yucca mountain or you treat it for reuse like they do in France.

Re: Out of all major energy sources, nuclear is the safest

#482

Post by JumpCrisscross » Mon, Jul 31, 2017, 7:59 PM UTC

logfromblammo wrote: post #460

JumpCrisscross wrote: post #175

Earlier quoted context omitted.

It's actually easier to leave the solar system than it is to hit the sun. (Earth orbits the sun at 30 km/s [1]. That means you need -30 km/s of ∆v to kill the energy we're born with. The escape velocity for our solar system from Earth's orbit, meanwhile, is about 42 km/s [2]. So you just need 12 km/s of ∆v to skip town.) [1] https://en.wikipedia.org/wiki/Earth%27s_orbit [2] sqrt((2 * 6.7E-11 * 2E30) / (150 * 10^6)) g…

That's good calculation there, but the number we're concerned with is the amount of ∆v that the spacecraft has to generate itself. If you just get close enough to the sun, a spacecraft could use the solar wind and solar magnetic field to shed more velocity, until it is close enough to aerobrake in the sun's atmosphere. Once you're out in the Oort cloud on the way out, you can't exactly deploy a solar sail to get anot…

The outermost layer of the Sun ends at 0.1 AU [1]. To put that in perspective, Mercury orbits at between 0.3 and 0.5 AU [2]. (It costs about 13 km / s to get to Mercury exiting from LEO.)

It's much cheaper to fling things out of the Solar System than into the Sun.

[1] https://en.m.wikipedia.org/wiki/Sun#Atmosphere

[2] https://en.wikipedia.org/wiki/Mercury_(planet)

Re: Out of all major energy sources, nuclear is the safest

#483

Post by pbreit » Mon, Jul 31, 2017, 8:00 PM UTC

payne92 wrote: post #13

I believe the politicization of nuclear energy (the resulting lack of investment & innovation) will go down as one of the major blunders in human history. We'd be in a far, far better situation with greenhouse gasses if we (as a human race) had continued to invest in nuclear energy. There would have been mishaps along the way, but at a much smaller scale than we're experiencing now with deaths from air pollution and…

I suspect the opposite argument could easily be made (if going big into nuclear somehow caused human extinction, which is easy to envision).

Re: Out of all major energy sources, nuclear is the safest

#484

Post by AdamJacobMuller » Mon, Jul 31, 2017, 8:01 PM UTC

Animats wrote: post #458

It doesn't kill many people, because even when there's a disaster, there's time to evacuate. But you lose an entire city once in a while. Major reactor disasters so far: - SL-1. Steam explosion due to control rod lifted too far during maintenance. Small experimental reactor, built in the middle of nowhere (Idaho Reactor Test Station) for good reason. Inherently unsafe design. - Three Mile Island. Meltdown due to cool…

> Some of the recently-touted small reactor designs try to omit a containment vessel on the grounds that their design couldn't possibly melt down. That's probably not a good approach.

Agreed, but, fail-safe and walkaway-safe designs coupled with moderate containment vessels seem like a good medium. It is all about mitigating risk. I don't think we should ever accept that a design has actual 0 risk for meltdown, but, if you design with a goal of having 0 risk of uncontained failures and then design containment for a moderate level of failure, that seems like you have a robust overall solution.

Re: Out of all major energy sources, nuclear is the safest

#485

Post by JoshMnem » Mon, Jul 31, 2017, 8:02 PM UTC

Arguments for nuclear power tend to ignore a few things:

- They talk about ideal power plants, but not actual power plants. Are they assuming that when the world switches to nuclear, that every country will build these ideal types of plants and maintain them well?

- Pro-nuclear arguments don't talk about inevitable wars. When nuclear power plants are scattered across the world in countries that will eventually become unstable, the potential outcomes look different. We are living through an amazing time for peace in many countries, but it isn't a given that things will remain peaceful like this.

- Radiation has a cultural effect as well, and those plants and storage facilities make likely targets, since radiation disasters tend to cause people to panic.

- After there is no more power from given plants or fuel, there is less incentive to take care of the waste and cleanup.

I'm not entirely against nuclear power, but I think that it's more complicated of an issue than most nuclear proponents claim.

Energy efficiency and use reduction are two other areas to consider. If it's possible to change behavior and opinions around nuclear energy then it should be possible to change behavior and opinions about efficiency.

Re: Out of all major energy sources, nuclear is the safest

#486

Post by nnfy » Mon, Jul 31, 2017, 8:02 PM UTC

People are using Fukushima to rationalize their fear of nuclear, just like we did after Three Mile Island and and Chernobyl. As someone else confirmed by posting [1], the magnitude 9.0 earthquake and 15 meter tsunami have not happened for at least 100 years. We can tear the plant down in hindsight, but it was designed to withstand probable events, just like any safety standards. It may not be pleasant to speak of human life in this manner, but there is always a cost/risk balance in any human endeavor, and this failure does not necessarily indicate recklessness.

1.http://www.world-nuclear.org/information-library/safety-and-...

Re: Out of all major energy sources, nuclear is the safest

#487

Post by gaius » Mon, Jul 31, 2017, 8:04 PM UTC

nothrabannosir wrote: post #293

KGIII wrote: post #109

Earlier quoted context omitted.

I will try to explain it as best as I can. Radioactive material decays as particles are emitted. If it has a long half-life, that pretty much means that the energy is being released rather slowly. In other words, just don't go poking at it and you'll be fine. On the othe hand, stuff with a short half-life means that atoms are decaying rapidly. Particles are being knocked off with great rapidity. That stuff is much mo…

[Same here] From what I remember, the energy released by γ-radiation is quite low. I'm still not convinced that just because something emits γ-radiation, short or long half life, it has an inherently meaningful energy potential. α- and β-radiation: sure. But γ? It's harmful to humans for very different reasons than fissile material is a useful energy source, isn't it? Or am I completely misremembering this all?

Correlation is not causation sure. But "spent" nuclear fuel has plenty of energy left in it that a breeder can extract.

Re: Out of all major energy sources, nuclear is the safest

#488

Post by beat » Mon, Jul 31, 2017, 8:04 PM UTC

yodsanklai wrote: post #457

oelmekki wrote: post #354

Earlier quoted context omitted.

This is a debate we have all the time, here in France, where we chose nuclear energy as main source of energy for several decades. Nowadays, everybody but lobbyists (because for those reasons, nuclear industry is strong, here) seems to agree renewable is the way to go (but we're far to be able to replace nuclear with renewable), mainly because: * we don't know what to do with nuclear wastes, and we start to have a lo…

> renewable is the way to go Everybody agrees with that. The question is whether we choose nuclear or coal during the transition to 100% renewable (if it ever happens). > we don't know what to do with nuclear wastes, and we start to have a lot > you have to dismantle old nuclear plants, and it appears the cost is totally exuberant I don't know if it's that bad. But again, is this worse than coal?

Why do you need a transitional solution? Why not Manhattan-Project the heck out of a purely renewable replacement? Coal is, for a variety of reasons, a terrible stopgap. And nuclear buildout is too slow and expensive.

For the cost of building significant new nuclear, we could build the new storage mechanisms, and all the solar/wind needed. Faster.

Re: Out of all major energy sources, nuclear is the safest

#489

Post by nnfy » Mon, Jul 31, 2017, 8:06 PM UTC

lispm wrote: post #211

nnfy wrote: post #170

Earlier quoted context omitted.

"Good" design is ill defined. The fact that a design is riskier than an alternative does not immediately make it worse. Especially when safety can be engineered to arbitrary standards with enough money.

> Especially when safety can be engineered to arbitrary standards with enough money. There is not 'enough money'. If a reactor shows cracks in the steel in critical places, preventing this upfront might not be technologically possible and afterwards repairing might also be so expensive, that it economically makes no sense. The big problem: if there is a technical problem, it is politically a very tough decision to cl…

The fact that a reactor may be failing after decades of use does not make it a poor design.

One optimizes for longevity during design, as well as other factors which cost money. It may have, for example, been cheaper to construct, with a strict lifetime after which it would be taken down."Good design" is almost always subjective.

That politics drive nuclear operators to maintain plants past their lifetimes does not indicate poor engineering.

Re: Out of all major energy sources, nuclear is the safest

#490

Post by gwbas1c » Mon, Jul 31, 2017, 8:11 PM UTC

bsder wrote: post #406

fsloth wrote: post #384

Earlier quoted context omitted.

Yes, it's much better to burn up the fuel and spread it into the atmosphere where it will cause a massive climate change. Note:I'm comparing nuclear to fossil fuels which was the only tradeoff until some time ago.

> Note:I'm comparing nuclear to fossil fuels which was the only tradeoff until some time ago. Last I checked, it still is. Solar can't get anywhere near baseline production that we need currently due to lack of storage options. And solar is the only thing which currently has even the possibility of scaling.

I can build a house today in the Northeastern US that's completely solar powered and off-grid. It adds about 15% to the cost to build. (2500 square foot home, 68k for panels, 18k for batteries, an extra 5k for a heat pump instead of a gas or propane heater.) The price of the panels and batteries is only going to drop.

For on-grid solar, the panels are already the cheapest form of energy available, when paired with a heat pump instead of natural gas. (When paired with using a giant resistor they cost equivalent to natural gas.)