[ExI] Small scale solar payback time (was Re: Planetary defense)

[Brent Neal]

On 22 May, 2011, at 4:12, Eugen Leitl wrote:

> On Sat, May 21, 2011 at 02:03:43PM -0700, Damien Sullivan wrote:
> 
>> What does order of magnitude improvement mean for solar panels?  You can
>> get 15% efficiency today, there's not an order of magnitude of
> 
> You can order 17% mono-Si immediately, up to 22% which is not
> yet readily available, and for research-grade (most of them
> concentrated) they're rapidly approaching 50%
> 
> http://upload.wikimedia.org/wikipedia/commons/e/ed/PVeff%28rev110408U%29.jpg 
> 
> So there's no orders of magnitude available, unless they're binary,
> then you'd get a couple at best. Longevity is up to 40+ years by now,
> so the only other improvements is price, material availability, and 
> EROEI.
> 

You're presuming that efficiency is the best metric for solar panels. I would suggest that measurements such as $/watt installed, $/watt amortized and DCF payback time, which are much more relevant to "real world" solar rollout and order of magnitude improvements in those numbers would be profound.

B



--
Brent Neal, Ph.D.
http://brentn.freeshell.org
<brentn at freeshell.org>