It is time to stop quivering in our boots in pointless fear of the future and just roll up our sleeves and build it.
- Ray Pierrehumbert

Tuesday, December 15, 2015

Like It or Not, We Need Nukes

According to this TED talk, sustained power delivery from solar is less than 10 W / m^2, which means 1200 m^2 / capita for current US consumption, times 350 M people = 4200 Million m^2 = 420,000 km^2 = larger than Montana. And that is optimistic and doesn't account for storage/intermittency.

In reality, at least double the area of Texas needs to be covered with solar panels, plus we need to solve the storage problem, to solve the problem on renewables only.

Can Americans get by on less than 12 KW? Well, most people in other countries do, but, realistically, Americans don't like to be told to cut back, and the ones who consume above the average all the more so.

Similar constraints hold for wind.

Only nuclear power allows us to continue the growth economy. And while you and I might not approve of the growth economy, people will not willingly give it up very soon. (It would pretty much kill most people's retirement strategy, for one thing.) And very soon is when we need a solution.

So I have concluded that like it or not, we need nukes.

24 comments:

Rob Ryan said...

People do respond to price signals though. I calculated my family's overall energy primary energy conversion rate a few years back and it came to around 40 kilowatts for the four of us. It's likely higher now that my son is driving though, on the other hand, my wife is driving less. In any case, even though we're profligate energy users, our demand is not inelastic and I think that that's true for many. A steep carbon tax would significantly reduce our consumption (with unknown unintended consequences) though I'm not sure that it would be reduced to the level of, say, the average EU nation. So I'm not sure that the land demand you posit would be necessary.

That said, there is little question in my mind not only that nuclear is necessary but that it will be implemented. The current civil and political obstacles will be demolished when significant widespread sacrifice would otherwise be unavoidable. The same can be said for current regulatory hurdles for other sorts of development.

rab said...

We aren't taking any particular precautions, have a 2300 ft^2 home, 2 cars.
BCHydro says our house uses avg. 1kW electricity.
Fortis says avg. for nat. gas is 3kW, through year. That is 6kW in winter, 0 in summer.
Commuting, using gas at 32GJ/l times 40l/wk/7/24/60/60=2.4kW.
Wife uses about 1.5kW. So total is 4kW. But this is using very inefficient internal combustion engines; only 25% or so. If we commuted by electric vehicle, would be 1kW.

So we use 8kW if gas cars, 5kW if electric. For 2 people.

What am I missing? 12kW per person seems rather excessive.

rab said...

We aren't taking any particular precautions, have a 2300 ft^2 home, 2 cars.
BCHydro says our house uses avg. 1kW electricity.
Fortis says avg. for nat. gas is 3kW, through year. That is 6kW in winter, 0 in summer.
Commuting, using gas at 32GJ/l times 40l/wk/7/24/60/60=2.4kW.
Wife uses about 1.5kW. So total is 4kW. But this is using very inefficient internal combustion engines; only 25% or so. If we commuted by electric vehicle, would be 1kW.

So we use 8kW if gas cars, 5kW if electric. For 2 people.

What am I missing? 12kW per person seems rather excessive.

Michael Tobis said...

Embodied energy of production, and public sector costs.

Michael Tobis said...

Also commercial air travel if you do any of that. Some people travel a LOT and definitely bring that average up.

William Connolley said...

Your TED talk link is https://www.blogger.com/blogger.g?blogID=8524070301101240472, which is forbidden to me.

If you like numbers http://www.withouthotair.com/ is good; for example http://www.withouthotair.com/c6/page_44.shtml

Michael Tobis said...

Fixed. Goes to show how many people do or don't follow links.

William Connolley said...

And it turns out to be my man :-)

JamieB said...

Is that 12kW primary energy consumption? If so it's not a particularly meaningful comparison because switching to renewables would mean you won't have thermal plant and internal combustion engines rejecting half of the energy to the atmosphere. Final energy consumption is a much better comparison when considering renewables.

A largely renewable society will require deep cuts in demand to substantially below current European levels. If you guys are inherently unable to get your energy consumption down then your conclusion is probably correct. Society can change though.

Bård said...

if the premise is wrong the conclusion is likely to follow.

Although I don't have very big qualms about nuclear (it certainly has some advantage over solar, it seems), the premise that you can't reduce energy consumption down to typical European levels probably escapes the characterization of naive, but not cynic, in my opinion.

Except the "American way of life" and the political situation, what is really holding America back from getting down to levels of Europe (which still is unsustainable)?

Bård said...

if the premise is wrong the conclusion is likely to follow.

Although I don't have very big qualms about nuclear (it certainly has some advantage over solar, it seems), the premise that you can't reduce energy consumption down to typical European levels probably escapes the characterization of naive, but not cynic, in my opinion.

Except the "American way of life" and the political situation, what is really holding America back from getting down to levels of Europe (which still is unsustainable)?

Arthur said...

Those numbers seem unlikely - JamieB points out one problem (not all "energy" is the same, and electricity is of highest quality, 1 kW electric is worth roughly 3 kW from burning stuff). But I doubt the 10W number just as much - incoming light averages well over 100 W per square meter over the entire surface of the planet, and efficiencies for solar panels are around 20% these days.

Worse though - where are the numbers on total nuclear installations to make up the difference here? 12 kW times 350 million people is over 4 TW - so we are talking about expanding our nuclear power supply by on the order of a factor of 10. This is more realistic?

Arthur said...

Those numbers seem unlikely - JamieB points out one problem (not all "energy" is the same, and electricity is of highest quality, 1 kW electric is worth roughly 3 kW from burning stuff). But I doubt the 10W number just as much - incoming light averages well over 100 W per square meter over the entire surface of the planet, and efficiencies for solar panels are around 20% these days.

Worse though - where are the numbers on total nuclear installations to make up the difference here? 12 kW times 350 million people is over 4 TW - so we are talking about expanding our nuclear power supply by on the order of a factor of 10. This is more realistic?

Tom said...

7 years is how long it took France to build most of its nuclear fleet. Something like 10 reactors a year.

Arthur said...

Correction - it's actually a factor of 40 for the US (we have about 100 active nuclear plants now producing about 1 GW each). So envision the nearest nuclear power plant to where you are now, and now imagine 40 plants within that distance, where now there is just one. 40 times as much uranium mines, 40 times as much radioactive waste to deal with, 40 times the risk of serious accident, 40 times the risk of nuclear material getting into the wrong hands. Is this really a better world than one with an area the size of Texas covered in solar panels?

Susan Anderson said...

Thanks to mt and WMC, I watched the Ted talk. Terrific starting point. Years ago a family friend recommended him, and his advice is excellent.

I have become acquainted with someone who really knows nuclear, and will see if I can edit his material down to where it will be accepted by this box:

"no reactor which is in any close prospect of being built "burns up its waste." It is theoretically possible, but only possible if a fast-flux reactor is coupled to what can only be described as a "fantastic" chemical separation and recycling process. .... nothing like the recycling needed to do this has been demonstrated (though the folks at Argonne do keep making laboratory progress) and the operational and safety problems of a fast-flux reactor AND a reprocessing cycle to do this are formidable.

"EBR-II and the Molten-salt reactors ... efforts were halted when they had demonstrated the reactors worked (at non-commerical scale, without commercial safety and operating conditions), but that the reprocessing trials were clearly failing to do all that was claimed or would be needed ...

"Overall the current state of waste reprocessing has been one ugly fiasco after another. Almost everything done to date (in any practical sense) has been derived from the Redox-plant chemistries developed for bomb production of plutonium. The plants (ours, the russians, the chinese, everybody's) that have done this did so for war purposes, mess and cost were no object .. and they all made a lot of both -- mess and cost. All of these plants are nuclear brown-fields today -- the Hanford site has spent billions in cleanup and still far from "clean.""

"Every civilian attempt to do reactor reprocessing via REDOX has been a commercial and environmental disaster, with the possible exception of the French reprocessing. ... isn't a commercial success. And REDOX only attempts to get U & Pu -- it does not fractionate the radioactive actinides from a waste stream.

"Aqueous REDOX plants are just horrible bad chemical engineering problems -- the list of ugly problems just gets deeper and deeper."

"the chemistry is generally open in the public literature now. ... reprocessing via aqueous REDOX is well-enough developed so that we know it cannot get clean enough to be a good civilian-power technology. It's ... bombs technology (coupled to production reactors run with very short fuel cycles to maximize Pu329 vs Pu240), and you don'r really care about cost or messes.

"The Argonne (and also Brookhaven) have done work on electrochemistry in melt-solutions. For civilian reactor cycles this is considerably more promising ... but [not great]. And building/running a fast-flux reactor where separated waste transuranic actinides (and/or the lighter waste actinides) are recycled back into the reactor to be "burned up" has never been demonstrated either. As far as this problem is concerned I think the issue of the actual "burnup" and end isotope distributions can be well-modeled ... that part of the problem isn't the severe one. But the problem of a fast-flux reactor that is undergoing continuous fueling/recycling has serious mechanical and safety issues."

Susan Anderson said...

wrt the previous, that was almost over my head but I thought somebody might be interested. The person who sent it to me gave me permission, and there's a bit more if wanted. It's off topic but compared to previous impressions I had garnered in my want-to-understand but math- and tech-challenged way, was very helpful to me.

I accept that we need nuclear, and had been trying to steer my way between the emotional extremes of totally not toxic versus totally toxic. One Ph.D. student at MIT did tell me that the waste is much better contained and protected than we imagine.

My worst-case on the coming decades involves a lot of infrastructure breakdown, and poor siting of existing plants and lack of political will to overcome resistance in installing better technology in safer locations appears to be to be a real handicap.

As Dr. MacKay says, let's talk but based on reality and without the hot air.

BBD said...

Arthur

I haven't had time to view MacKay's TED talk, but it will be based on MacKay (2013) which provides all the empirical data you require to demonstrate that 10W/m^2 for SPV is generous.

BBD said...

Anyone wanting more on the detail behind MacKay's TED talk may want to have a look at MacKay (2013).

For example:

solar photovoltaic farms in Bavaria, Germany, and Vermont, USA, deliver 4 watts per square metre; in sunnier locations, solar photovoltaic farms can deliver 10 watts per square metre; concentrating solar power stations in deserts might deliver 20 watts per square metre.

For the numbers, see Fig. 8 and Table 1. 1W/m^2 is a fairly generous estimate for power per unit area for large SPV arrays.

Michael Tobis said...

"Although I don't have very big qualms about nuclear (it certainly has some advantage over solar, it seems), the premise that you can't reduce energy consumption down to typical European levels probably escapes the characterization of naive, but not cynic, in my opinion."

I think it is harder than you think for America to downshift by the factor of two that would match Northern Europe. But that's not the point. There are billions of people who would reasonably claim that the extant world order carries an implicit promise that they can scale UP to the European level. And that's a promise we don't seem likely to keep without nuclear.

Michael Tobis said...

rab, watch the video. there are hidden consupltions as well.

BBD said...

mt

Thanks for fishing my comments out, even if I only now notice an order of magnitude typo :-)

December 23, 2015 at 7:40 AM should of course be:

10W/m^2 is a fairly generous estimate for power per unit area for large SPV arrays.

And Happy New Year :-)

Michael Tobis said...

Sorry for slow turnaround, everyone. Should be back on my game soon.

Gingerbaker said...

Huge math error?

4200 million square meters = 4.2 billion square meters = ~1600 square miles . Montana = 147,000 square miles

or is this some strange British-ism?