[ExI] [tt] Smaller, cheaper, faster: Does Moore's law apply to solar cells?

[Kelly Anderson]

On Mon, Mar 21, 2011 at 4:41 AM, Eugen Leitl <eugen at leitl.org> wrote:
> On Mon, Mar 21, 2011 at 01:17:04AM -0600, Kelly Anderson wrote:
> It is a nice article, it however glosses over (deliberately?)
> in how photovoltaics is not like Moore's law.

Exponential  curves are exponential.. in what way is it not like
Moore's? In the doubling period? In that it isn't feature based? I
like Kurzweil's term "Law of Accelerating Returns" a little better
than "Moore's Law".

> Thankfully, even
> by doubling very little (from 1% to 2% over a year) you can
> achieve e.g. 12.5% of peak (e.g. yesterday http://imgur.com/nu9D7 ),
> and have to deal with interesting problems like
>
> http://www.renewablesinternational.net/yes-we-have-no-base-load/150/537/29353/

This article seems to say two things
1) The grid isn't ready for as much solar as they project they will get
2) Because of government subsidies, solar growth is too fast.
3) It brings up the question of what to do with extra capacity (I
think a partial solution to that is pretty easy)

> It seems like I need to start budgeting for a WhisperGen.
> Can't really argue with a quiet, affordable appliance with >90% efficiency.
>
>> solar cells are half of the expense of a single home system. The other
>> half are batteries (which are on a similar cost reduction curve) and
>
> Batteries are no good at the moment. I would rather buy a decent
> on-demand diesel -- or abovementioned WhisperGen, running of LNG.

I have a Honda inverter that generates 7000 watts. I am a huge
believer in these Hondas. They are quiet, they last a long time.
Fixing them is a little expensive, but not needed very often

>> inverters (which to my knowledge are not).
>
> There are panels with integrated inverters now.

You can bet they aren't following a Moore's curve then... ;-)

> You could also synthesize
> AC in realtime from individual cell's contribution (perhaps using
> capacitors to prevent wasting crossing zero). But I definitely do
> like DC very much, with DC/DC converters, and DC/AC when you
> absolutely, positively need to have AC which I don't think is
> very often.

Living without AC is hell. Finding DC appliances is very hard, and
they always have stupid limitations, like very small refrigerators,
half powered microwaves, and they are always very expensive. If the
appliances were reasonably priced, and not SO focused on conservation,
it would be easier.

>> Nanosolar is investing in 100 house sized installations that live in a
>> field nearby, not on your own roof. There are a lot of benefits to
>
> It should be your roof, not being on your roof. And facades.
> http://inhabitat.com/germanys-solar-coated-surplushome-wins-solar-decathlon/

That's all fine, but it still requires that your roof be within a
couple of hundred feet of some kind of inverter or storage system. DC
loses power very quickly over lines (as I understand it). My
electrician was against putting a windmill 300 feet away from the
house due to the potential loss. Granted, he might have been an
idiot... :-)

>> this approach, since people don't need their own inverters or
>> electrical storage systems. For this type of installation, the cost of
>> the cells themselves becomes much more important, and Nanosolar and
>> the other continuous film producers are getting the cost down at a
>> very quick clip.
>
> The bottleneck is not inking up the sheet metal, the bottleneck
> is putting it up, wiring it up and upgrading the grid to a P2P
> model. Dinosaurs don't understand agile producer swarms.

True enough, but there is also equipment required.

>> So my view of the future is not so much solar on every rooftop. At
>> least not for quite a while. Even though it's on my roof top, but for
>> unusual reasons.
>
> Insular PV will help terraform Arizona and Texas.

Ya. I figure that's where our hydrogen will eventually come from. Of
course the environmentalists will continue to have a problem, even
though solar is what they have been asking for for decades. I think
most environmentalists are actually  just anti-capitalists in sheep's
clothing, but that is another thread.

-Kelly