[clug] OT: Solar power recommendations and advice

Felix Karpfen felix.karpfen at gmail.com
Tue Apr 20 15:21:18 MDT 2010


On Tue, 20 Apr 2010 20:59:33 +1000, Paul Wayper wrote:

> As Alex said, that power goes *somewhere* and you get paid for it, end 
> of story.

>  It will have contributed to reducing the load on a coal-fired power
>  station somewhere, no questions asked.  

This is the point at which I stalled 3+ years ago, when I looked into the 
matter.

As pointed out in the previous (not quoted) posting, power stations will 
fire up enough generators to supply the anticipated demand (based, 
presumably on previous usage patterns) and it takes some hours for the 
generators to come up to speed and produce electricity at the most 
economic cost.

If the producers get it wrong, you either get brown-outs (when there is 
not enough to meet the demand) or waste (when some of the available 
electricity does not find a buyer). 

So electricity producers have greater flexibility than my initial 
simplistic analysis uncovered.  However, the basic conclusion holds.  
They will continue to match the anticipated demand as long as the revenue 
from that demand exceeds their total costs.

My other complaint against solar-cell electricity (not previously voiced) 
is that it is stunningly inefficient.  I am advised that the theoretical 
maximum conversion of solar power to electricity is about 33%.  The (1st 
generation) cells currently marketed in Australia (based on silicon) 
achieve conversions of 12-13% max. 2nd generation cells (currently 
marketed in the US) achieve an 18%+ conversion; 3rd generation cells can 
be found in laboratories at the ANU; I know nothing of their capabilities.

Finally - although this is OT raised to a higher power - the best (and 
cheapest) way to cut electricity-generated greenhouse gas emissions is to 
reduce demand.  I chose that route by insulating the walls and ceilings 
of my house and installing double windows. No brownie points for 
originality; both are standard practice in much of Europe and in Canada. 
I also installed the European version of "solar hot water" (Dux SunPro in 
Australia).  The total cost was a fraction of the cost of solar panels.

Felix Karpfen
-- 
Felix Karpfen
Public Key 72FDF9DF (DH/DSA)




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