Why nuclear energy is our best option at the moment • Hacker News Board

Re: Why nuclear energy is our best option at the moment

#231

Post by epistasis » Tue, Nov 03, 2015, 11:41 PM UTC

ageofwant wrote: post #225

yazriel wrote: post #187

The article is completely unprofessional. The tone itself is very one-sided - which is bad enough. However, the factual omissions are ridiculous. Here are a few examples: the area used for wind turbines is large, but it is usually re-usable for agriculture, or increasingly off shore official nuclear death are low - but there is a lot of dispute on the "long tail" of long term deaths from the big nuclear disasters of…

You assert that an article of this nature needs to be "professional", why is that ? It was written for the great mass of laypeople that (supposedly) holds the power over our nuclear future. It is intended to challenge the ongoing anti-nuclear narrative and re-educate. It achieves those aims admirably. While your criticisms may be arguably valid for a different audience they are irrelevant here.

I didn't mean to downvote you but accidentally clicked on the button and can't go back.

However, I do disagree with your point. I'm pro-nuclear to the degree that it's economical, and found the article to be somewhat insipid due to grandparent's reasons.

Just as there are plenty of people that are irrationally anti-nuclear, being irrationally pro-nuclear is no better at all.

Re: Why nuclear energy is our best option at the moment

#232

Post by vlehto » Tue, Nov 03, 2015, 11:41 PM UTC

bluthru wrote: post #226

vlehto wrote: post #164

Earlier quoted context omitted.

1. You can make same argument about any energy recourse. "we need so big number of them, that it's futile." I guess my grandchildren will die then. 2. No way to recycle.. Except there is. Over half of current energy production happens in countries that already have nuclear weapon, or are part of NATO. So because Ghana can't have heavy water nuclear power plant, U.S. can't either? 3. Price going up with the cheapest f…

>"we need so big number of them, that it's futile." I guess my grandchildren will die then. You can build a lot of PVs and turbines in the same amount of time, and place them closer to where they're being used (reduce transmission loss). You can also place them on top of buildings (reduces AC load by 2%) and on top of parking lots (reduces car heat and urban heat island effect). You're not going to electrify poor par…

>You can build a lot of PVs and turbines in the same amount of time, and place them closer to where they're being used (reduce transmission loss). You can also place them on top of buildings (reduces AC load by 2%) and on top of parking lots (reduces car heat and urban heat island effect).

That was not the point. The argument was that nobody can build all the hundreds of nuclear plants that we would need. How can we build the millions of PV's and thousands of turbines?

>You're not going to electrify poor parts of the world with big, expensive, centrally-controlled fission plants.

Why not? It's probably the cost/watt that matters.

>transmission loss

Most of world population lives close to coastline.

>It will cost over $100 BILLION to clean it up.

Nuclear power might still be cheaper as a whole.

Re: Why nuclear energy is our best option at the moment

#233

Post by acqq » Tue, Nov 03, 2015, 11:42 PM UTC

yazriel wrote: post #187

The article is completely unprofessional. The tone itself is very one-sided - which is bad enough. However, the factual omissions are ridiculous. Here are a few examples: the area used for wind turbines is large, but it is usually re-usable for agriculture, or increasingly off shore official nuclear death are low - but there is a lot of dispute on the "long tail" of long term deaths from the big nuclear disasters of…

> There is simply not enough uranium for a full build out of 3rd generation nuclear

This is really important and is often avoided to be discussed: even if the 10% of all world's energy needs are covered by the nuclear energy at this moment, we know we're using some 70 Ktons of uranium per year. Then to use only nuclear energy we'd need 700 Ktons per year. Currently identified uranium resources total 5.5 Mtons, which would last for less than 8 years of such use. Even if those aren't the exact numbers, that are the orders of magnitude.

That's why the breeder reactors would be needed as a "solution," and at the moment they are still experimental, especially regarding the fulfillment of their major promises.

The current state of FNRs:

http://www.world-nuclear.org/info/Current-and-Future-Generat...

The two only "commercial" plants currently planned are in Russia (from mid-2020s, U+Pu nitride fuel) and China (from 2028, U-Pu-Zr fuel).

Some problems with the breeders are mentioned in

http://fissilematerials.org/library/rr08.pdf

Re: Why nuclear energy is our best option at the moment

#234

Post by KingMob » Tue, Nov 03, 2015, 11:46 PM UTC

Turing_Machine wrote: post #128

anon1mous wrote: post #122

Earlier quoted context omitted.

Very simple - a few tones of Uranium or Plutonium, dispersed in air or water can kill the population of a continent.

Very simply, you're wrong. Badly wrong. http://spectrum.ieee.org/energy/nuclear/nuclear-fuel-from-th... The ocean contains 4.5 billion tonnes of uranium already. 4.5. BILLION. TONNES. Dispersed in water. I haven't noticed any continents dying off because of this, have you?

But it's well-known that dying continents leave the pack and slink off into the mantle to die alone, so you wouldn't necessarily have seen it.

Re: Why nuclear energy is our best option at the moment

#235

Post by ageofwant » Tue, Nov 03, 2015, 11:46 PM UTC

frankus wrote: post #200

If they're going to have something called a NERD NOTE, they should at least get their units right: "The entire planet’s electrical consumption is right around 5 terawatt-hours." 5TWh per what? Per second? Per hour (then why not 5TW?)? Per year? Cumulative over all of human history?

Watt is joule/second.

Write it out and algebraically cancel the units and you'l understand that you don't understand, and then maybe you will.

As a rule, in future, try to understand before mocking, its a better way to live, take it from me...

Re: Why nuclear energy is our best option at the moment

#236

Post by beefman » Tue, Nov 03, 2015, 11:46 PM UTC

novalis78 wrote: post #139

NolF wrote: post #108

Earlier quoted context omitted.

The design and safe construction does.

Very informative read and eye opener on this topic: http://thorconpower.com/costing/should-cost-versus-did-cost

Additionally, many people are completely unaware of the vast variety of fission machines of all shapes and sizes -- rocket engines, ramjet engines, space power reactors, research reactors, isotope production reactors, submarine power reactors, Army mobile power reactors, etc. -- that were produced and operated 50 years ago. To say nothing of the variety we could build with today's metallurgy, CAD, etc.

Re: Why nuclear energy is our best option at the moment

#237

Post by beat » Tue, Nov 03, 2015, 11:47 PM UTC

chc wrote: post #215

beat wrote: post #213

Earlier quoted context omitted.

Run the numbers on it. What's a reasonable expected area for a real-world nuclear power plant? (not the fantasy of the OP, but what real plants usually cover) Reasonable peak and median output long-term for that much solar panel? Throw in some batteries for storage to stabilize the output, and the numbers are pretty compelling. Then throw in the cost of covering, say, a square mile of land with solar panels versus th…

A sibling commenter already did run the numbers on it, and found nuclear ahead by a factor of 10: https://news.ycombinator.com/item?id=10503382

The Ivanpah plant isn't a great example. The tech is already going obsolete, and it's producing far below theoretical effectiveness. It should be able to produce a terawatt. Fundamentally, it's because solar is immature technology, and nuclear is mature. So what would the efficiency and cost be for a mature solar plant? And how do we get to maturity?

If a solar plant could hit 50% of the energy efficiency on the same land (and the poor-performing Ivanpah plant reveals that it's possible), that raises a question of why we need the cost and complexity of nuclear.

Re: Why nuclear energy is our best option at the moment

#238

Post by neltnerb » Tue, Nov 03, 2015, 11:48 PM UTC

InclinedPlane wrote: post #171

pjc50 wrote: post #100

"We could do it for $1 Trillion with liquid-fueled Molten Salt Reactors, on the same amount of land, but with no water cooling, no risk of meltdowns, and the ability to use our stockpiles of nuclear “waste” as a secondary fuel." This is not a production-ready technology, though. I believe there are lingering problems with corrosion. And the claim that the MSR doesn't require secondary water cooling is odd: what's the…

Corrosion is not a problem. But there is still a ton of work that needs to be done with molten salt reactors. But it's work we should do, I feel. I used to be skeptical of the idea but after doing a considerable amount of research I changed my opinion, the core design has a myriad of advantages and it's practically criminal we aren't dumping gobs of money into research for it. As for water, the working fluid of the h…

Wait wait wait, you're going to have to provide a citation for this claim that corrosion is not a problem.

I was told by faculty with joint appointments in matsci and nuclear engineering that it is a major issue and that while they've developed some alloys that look reasonable in the recent past it's still academic research unproven in scale up.

Holding molten salts is really hard... they corrode the heck out of even high end commodity stainless steels (this I know from professional work). Protective coatings help for sure, but they crack over time, especially with any thermal cycling. Inconel and similar alloys maybe, but it's really not straightforward to block grain boundary corrosion! Add to that neutron embrittlement...

I've not kept super up to date, but it's hard to imagine that these alloys went from academically unproven to industrially certified in the last seven years.

Re: Why nuclear energy is our best option at the moment

#239

Post by merb » Tue, Nov 03, 2015, 11:51 PM UTC

adventured wrote: post #209

merb wrote: post #202

Earlier quoted context omitted.

it's true. somewhat. I mean the energy of the nuclear station stays constant. however the peak power of the solar panels will be higher. but I doubt that the solar panels will still be creating less energy over a longer period of time. unless you build both inside a desert and there you would have other problems like the sand which affects the lifetime of your panels, etc.. btw. i'm against nuclear and non renewable…

The peak power of solar panels is not higher today. The highest capacity US nuclear power plant can out-produce the best utility scale solar installation by 10 fold, with both at max capacity, on an equal amount of land.

no with peak power i mean. full sun no cloud the whole day, etc. perfect things wheater for solar energy. However this barely (never) happens. so the energy of the panel changes throughout the day. however highest (possible) peak of solar could definitly be higher than a nuclear power plant (anywhere in the world) on an equal amount of land.

nothing to do with today. just a "what would happen on a perfect day". peak vs peak. also peak of a nuclear power plant could be raised by human and solar panel peak is barely measurable, since there are a hugh amount of factors that could change it.

Re: Why nuclear energy is our best option at the moment

#240

Post by pjc50 » Tue, Nov 03, 2015, 11:52 PM UTC

jandrese wrote: post #144

pjc50 wrote: post #100

"We could do it for $1 Trillion with liquid-fueled Molten Salt Reactors, on the same amount of land, but with no water cooling, no risk of meltdowns, and the ability to use our stockpiles of nuclear “waste” as a secondary fuel." This is not a production-ready technology, though. I believe there are lingering problems with corrosion. And the claim that the MSR doesn't require secondary water cooling is odd: what's the…

Yeah, there are a lot of alternate nuclear reactor designs that look great on paper but have never had the full scale engineering done to see if it is practical. And they look cheap because you don't even know half of the stuff you have to do that makes it expensive. It's like rocket design where you go "just put a bunch of explosives in a tube and go into space, this shouldn't be too expensive or difficult..."

This is where John D Clark's book "Ignition!" really shines: it's the history of the science of rocket fuel as problem solving. Plenty of candidates on paper, need to be tested for detonation, hypergolicity, ease of ignition, handling, effect on plumbing etc. Red fuming nitric acid is a good example: great oxidiser, doesn't need cryogenics but is liquid even in arctic temperatures. Only problem is it eats through the tanks, until they discovered that adding a small quantity of HF made it OK to store in stainless steel.

I suspect that he would have taken one look at handling radioactive corrosive liquid at 600C and asked to go back to the nice safe rocket lab with only a few explosions.