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[Discuss] Eclipses Re: Great talks last night, however...



On 7/23/2017 3:42 PM, grg wrote:
> In the paper they show that a conventional li-ion battery holds 90% of the
> original charge after 3000 cycles (~9 years of daily cycling); and after

BS.

http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries


> Nor do those characteristics describe millions of homes and buildings.  How
> many buildings do you think are destroyed in Kansas by tornados each year?
> Hundreds, for a survival rate of 99.99%.  So no, it's not because cows are
> running away from approaching tornados or because they're sharing Farmer
> John's storm cellar, it's actually because 99.99% of the spots in Kansas
> don't have a tornado land on them.

The size of a home or even a large barn in rural Kansas is a tiny
faction of the size of a 150km^2 (say) power station. Rural homes in
Kansas are spread out dozens to hundreds of kilometers apart. So when a
tornado touches down the chances of hitting a given home is small and
the chances of it hitting several is practically nil.

Unless it hits Topeka.

That 150km^2 power station? That's the size of Topeka which got
clobbered by a sequence of tornadoes in 1966.


> I guess you'll be surprised to learn that the ground is actually an
> effective heat sink; see the ground loops in heat pumps, which provide air
> conditioning by sinking the removed heat into the ground.  Here's a source
> for you:  https://energy.gov/energysaver/geothermal-heat-pumps

The ground can hold a lot of heat energy but it doesn't conduct it much.
That's why a GHP spreads its ground loop system out across a large area.
You're not getting that from burying big battery packs unless you also
install the same kind of extensive ground loop system which costs to
install and maintain. Oh, and you've added an extra vulnerability to
earthquakes. Yay.

Can ground-based work? Maybe. I don't think so. But even if it can be
done? It's still just a stop-gap being marketed as a solution by a man
who has a vested interest in selling batteries.

-- 
Rich P.



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