I think the big win might be desalination, in terms of the developing world.

Conservatively, a 5MW unit could desalinate 350,000 gallons an hour (at a cost of ~ 14kWh per 1,000 gallons [1]) ; maybe more if you were to use the waste heat as well.

If you assume American patterns of water usage, at 100 gallons per person per diem, that’s enough water for 84,000 people.

And it could even be the salvation of the West - if the primary use of the water is irrigation, that ties up a tremendous mass of carbon, gets the water cycle working again (all that transpiration == clouds == more rain == more plants). More clouds also means a greater albedo, and lower global temperatures.

Instead of spending hundreds of billions on oil wars, line the coast of the horn of Africa with desalination plants, turn the desert into an oasis, plant oil crops to feed the remaining internal combustion engines until electrical energy storage problems are cracked and people transition gradually to electric vehicles. No need to junk a whole generation of working vehicles, just go with normal obsolescence, and all that plant matter that’s not turned into fuel (stems, leaves, etc) is fixing carbon and literally saving the planet. There are even market motivations for this - if it was just food, there would be no market motivation to increase production so much without an attendant increase in population. But with the grease-guzzling giant of the Western automotive industry to feed, it’s not just an exercise in green-earth gardening, there’s a way to get big capital interested in funding it.

—-

[1] http://www.livescience.com/4510-desalination-work.html

Note that this is the *worst* figure I could find for desalination energy cost. The Wikipedia article on desalination implies that most modern processes use about 3kWh per cubic metre (1,000 litres), which would be about 11kWh for 1,000 gallons, and that Siemens have allegedly invented a process that consumes only 1.5kWh per cubic metre.

As with many things, the issue isn’t enough energy, but how much that energy costs.  In other words, the real question is how much per litre desalination via FF would cost, relative to conventional electrical power.

Dr_Barnowl - 13 December 2011 10:31 AM

I think the big win might be desalination, in terms of the developing world.

Conservatively, a 5MW unit could desalinate 350,000 gallons an hour (at a cost of ~ 14kWh per 1,000 gallons [1]) ; maybe more if you were to use the waste heat as well.

It’s as Tulse said. The purpose of these elaborate techniques is to lower the energy costs of the process… but in turn these techniques add to the cost of the process.

BTW there was a thread on exactly that topic…
http://focusfusion.org/index.php/forums/viewthread/1017/

If you postulate using an FF unit for desalination then you have broken that vicious circle. You have plenty of cheap power so it suddenly makes sense to use the cheapest separation method available: brute force evaporation. Boil the seawater, collect the freshwater steam.

If you have an FF unit available then using any other method would not make sense.

And along the lines of the estimates I used in that other thread: if you dedicate an entire FF unit just to desalination… say 12MWt with a few dozen KWe left over to power pumps, fans etc… then you come out with 400 metric tons per day at a cost of 5 cents.

Not 5 cents per ton… 5 cents per day.

zapkitty, how reasonable are your figures for the cost of FF electricity?  In the other thread you posit .2 cents/kwh—do you have a source for that number?

Tulse - 13 December 2011 04:11 PM

zapkitty, how reasonable are your figures for the cost of FF electricity?  In the other thread you posit .2 cents/kwh—do you have a source for that number?

That’s from LPP. They have a breakdown of estimated FF costs in the Google talk and Lerner-hakase has used .02 kwh several times.

http://focusfusion.org/index.php/forums/viewreply/1060/
http://focusfusion.org/index.php/forums/viewreply/2369/

zapkitty - 13 December 2011 05:16 PM

Tulse - 13 December 2011 04:11 PM

zapkitty, how reasonable are your figures for the cost of FF electricity?  In the other thread you posit .2 cents/kwh—do you have a source for that number?

That’s from LPP. They have a breakdown of estimated FF costs in the Google talk and Lerner-hakase has used .02 kwh several times.

http://focusfusion.org/index.php/forums/viewreply/1060/
http://focusfusion.org/index.php/forums/viewreply/2369/

More recently, Lerner has quoted about 3¢, but it’s all tied up with mass mfr’g extrapolation, siting, etc.  But that’s the ballpark. Really, the capital costs get retired very fast, and then the ongoing maintenance is composed of electrode replacement and staffing costs.  These might amount to ~$60K/unit/year, for about 40 million kwh.  Which works out to ~0.15¢/kwh. 
Add whatever capital cost retirement fraction you consider reasonable. 

Brian H - 13 December 2011 11:32 PM

zapkitty - 13 December 2011 05:16 PM

Tulse - 13 December 2011 04:11 PM

zapkitty, how reasonable are your figures for the cost of FF electricity?  In the other thread you posit .2 cents/kwh—do you have a source for that number?

That’s from LPP. They have a breakdown of estimated FF costs in the Google talk and Lerner-hakase has used .02 kwh several times.

http://focusfusion.org/index.php/forums/viewreply/1060/
http://focusfusion.org/index.php/forums/viewreply/2369/

More recently, Lerner has quoted about 3¢, but it’s all tied up with mass mfr’g extrapolation, siting, etc.  But that’s the ballpark. Really, the capital costs get retired very fast, and then the ongoing maintenance is composed of electrode replacement and staffing costs.  These might amount to ~$60K/unit/year, for about 40 million kwh.  Which works out to ~0.15¢/kwh. 
Add whatever capital cost retirement fraction you consider reasonable.

I’m confused—I see .02 cents, .15 cents, .2 cents, and 3 cents as estimates.  Is there really two orders of magnitude uncertainty?  (Although even that high end is substantially cheaper than US power.)

Tulse - 14 December 2011 12:08 AM

I’m confused—I see .02 cents…

That was a typo on my part, should have read 0.2

Tulse - 14 December 2011 12:08 AM

.15 cents, .2 cents, and 3 cents as estimates.  Is there really two orders of magnitude uncertainty?  (Although even that high end is substantially cheaper than US power.)

It all depends on your starting assumptions and how much you assume mass production will bring costs down…

Brian, do you have a link or background on the 3 cents/kwh figure?

Just for comparison, it appears that the average price for residential power in the US in 2011 was around 11 cents/kwh, and the cost in most other countries is far higher.  These are “plant-to-outlet” costs that consumers pay, and not just generating costs—I don’t know if things like transmission system capital and operating costs are included in the FF estimate, or what percentage of the final consumer price those costs are.  It seems like FF-generated electricity will indeed be much cheaper than current power, but “much” may be more like “tens of percent”, and not “orders of magnitude”.  Given that, I doubt that we’ll see a lot of new power-hungry technologies enabled by FF, as I doubt that FF will make power cheap enough.

I think it’s also important to note, however, that FF is likely to have far fewer externalities associated with it (e.g., health effects of smokestack emissions, land consumption for plant siting, wear and tear on rail system from coal transportation, costs of fighting wars to protect oil-rich nations, etc .etc. etc.)—these are not factored into the current price of electricity.  I think personally that it is in eliminating those externalities that FF really shines.

My error.  Just a typo.  That was 0.3¢.