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Why nuclear energy is our best option at the moment

energyrealityproject.com

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

#251

Post by carpdiem »

ageofwant wrote: post #235
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...

I think you've misunderstood the point. Terawatt-hours is ambiguous, without specifying a time period.

In particular, Terawatt-hours can be converted to Joules. To say that humanity's energy usage is X Joules is meaningless without specifying the time period that that energy is used over. For example, it means very different things to say that humanity uses 5 TWh per day than to say that humanity uses 5 TWh per year (versus 5 TWh since the dawn of recorded history!).

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

#252

Post by badloginagain »

ju-st wrote: post #96

The German wikipedia does have some interesting references to reports on thorium reactors from the British National Nuclear Laboratories [1][2]: > In the foreseeable future (up to the next 20 years), the only realistic prospect for deploying thorium fuels on a commercial basis would be in existing and new build LWRs (e.g., AP1000 and EPR) or PHWRs (e.g., Candu reactors). Thorium fuel concepts which require first the…

Thorium in LWRs are inefficient. If you're going to use a LWR, use the fuels they were designed for. The efficiencies of Thorium only really come into play using a MSR.

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

#253

Post by bumbledraven »

mey wrote: post #245
pjc50 wrote: post #240

Earlier quoted context omitted.

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…

I've seen Ignition! referenced quite a few times on this site. Is there a reasonable place to get a reprint?

Googling for [john clark ignition] yielded http://fringe.davesource.com/Fringe/Explosives/Ignition.An-I... (also on archive.org)

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

#255

Post by JabavuAdams »

cthalupa wrote: post #185
toomuchtodo wrote: post #46

Earlier quoted context omitted.

> How do wind and solar provide a solid baseline power. Properly built and managed distribution networks, along with utility scale battery storage. > And China builds nuclear plants a lot faster and cheaper than we do, and no known accidents. Yet. China still gets more power from wind than nuclear, and they're building out wind generation capacity far faster than nuclear: http://www.earth-policy.org/data_highlights/2…

>And when you fail hard, it costs billions of dollars to cleanup: http://www.psr.org/environment-and-health/environmental-heal... . Using Fukushima as an argument against nuclear is such a silly thing to do, and the decades long freeze on any sort of real progress in meaningfully upgraded or new commercial reactors makes this sort of thing a self fulfilling prophecy. How many industries have catastrophic failures? Ho…

It's not just about trusting the technology, it's about trusting the human processes that govern and maintain that technology. You say that Fukushima could have been prevented, and yet -- it wasn't prevented.

Humans are greedy, generally corrupt, and bad at maintenance when things are going well. To really trust nuclear, we need better humans, since the accidents can be so catastrophic.

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

#256

Post by readams »

ageofwant wrote: post #235
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...

You might say, for example, that "in 2008, the world total of electricity production was 20,279 terawatt-hours (TWh)." You need the time period however for it to make sense. Referring to a continuous generation capacity would be measured simply in terrawatts. As in "this number corresponds to an average rate of around 2.3 terawatts continuously during the year."

The original article has an error as pointed out by the parent. Insert ironic mocking statement here.

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

#257

Post by paol »

mey wrote: post #245
pjc50 wrote: post #240

Earlier quoted context omitted.

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…

I've seen Ignition! referenced quite a few times on this site. Is there a reasonable place to get a reprint?

It's available online: http://library.sciencemadness.org/library/books/ignition.pdf

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

#258

Post by yongjik »

KingMob wrote: post #234
Turing_Machine wrote: post #128

Earlier quoted context omitted.

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.

Which is, ironically, only possible because of radioactive heat generated by the Earth.

Without radioactivity, there would be no continent to die in the first place.

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

#259

Post by 13thLetter »

tomcam wrote: post #21

I am not reflexively anti-nuclear. However, I have never heard a satisfactory answer to the simple question: "How do we store nuclear waste safely?"

a) How is "put it in Yucca Mountain" not satisfactory? b) Do you demand similar levels of safe storage for all of the hazardous materials, many of which are far more dangerous than nuclear waste, produced by other industries, including those involved in renewables technologies?

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

#260

Post by InclinedPlane »

neltnerb wrote: post #238
InclinedPlane wrote: post #171

Earlier quoted context omitted.

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…

Hastelloy-N, it's expensive stuff but it works. Corrosion is one of the difficulties of molten salt reactor designs, but it's manageable with the right materials. And the tradeoff is that you don't need an enormous high-strength containment vessel (because everything radiological is at 1 atm), you don't need to pump water into the thing constantly to avoid "really bad things" happening (Fukushima), etc, etc.
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