Xref: utzoo sci.energy:3715 sci.electronics:16707
Path: utzoo!censor!geac!torsqnt!news-server.csri.toronto.edu!cs.utexas.edu!samsung!olivea!bu.edu!att!rutgers!rochester!dietz
From: dietz@cs.rochester.edu (Paul Dietz)
Newsgroups: sci.energy,sci.electronics
Subject: Re: solar cells
Message-ID: <1991Jan4.173128.26484@cs.rochester.edu>
Date: 4 Jan 91 17:31:28 GMT
References: <1991Jan3.072059.20842@loop.uucp> <11515@pt.cs.cmu.edu>
Reply-To: dietz@cs.rochester.edu (Paul Dietz)
Organization: University of Rochester Computer Science Dept
Lines: 32

In article <11515@pt.cs.cmu.edu> lindsay@gandalf.cs.cmu.edu (Donald Lindsay) writes:
>In article <1991Jan3.072059.20842@loop.uucp> keithl@loop.uucp 
>	(Keith Lofstrom;;;628-3645) writes:
>>Most solar cells are made with processes that are similar to those
>>used to make integrated circuits.  A big IC fab turns out on the
>>order of a million wafers a year, and turns out tens of thousands of
>>gallons of liquid toxic waste and hundreds of thousands of cubic feet
>>of gaseous waste in the process.  
>
>>Scaled to nuclear plant size, that's millions of
>>gallons of waste per year for the same amount of power.
>
>I detect a humongous assumption, namely, that cell fab and chip fab
>use the same amount of processing per area.

Another assumption: that the area of the cells = the area of the
collector.

In fact, if sophisticated, expensive single crystal Si, GaAs or high
performance tandem cells are ever used on earth on a large scale, they
will be used with lens/mirror concentrators at concentration ratios of
100 or greater.  This only works in areas with lots of direct sunlight,
like the southwest, but that's the sunniest part of the country anyway.

Flat plates, if they are to have large grid-connected market penetration,
have to be very cheap, which means using thin layers of more crude
materials deposited by cheap techniques (for example, electroplated
CdTe).  These polycrystalline or amorphous materials are of much
lower quality (and cost) than the materials used in IC manufacture.

	Paul F. Dietz
	dietz@cs.rochester.edu