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[Bill Jones <billj AT harborside.com>]

> Breakthrough in solar photovoltaics
>
> THE HOLY Grail of researchers in the field of solar photovoltaic (SPV) 
> electricity is to generate it at a lower cost than that of grid 
> electricity. The goal now seems to be within reach.
>
> A Palo Alto (California ) start-up, named Nanosolar Inc., founded in 
> 2002, claims that it has developed a commercial scale technology that 
> can deliver solar electricity at 5 cents per kilowatt-hour.
.......

> The flagship product, Nanosolar SolarPly, is a 14 feet x 10 feet solar 
> electricity module delivering 120 watts per square inch at 110V. The 
> company is now offering solar panels at below $1 per peak watt.
The first problem I found with this is that solar cells are usually 
described in terms of the price per watt (the RATE of energy output), 
not KWH (a measure of total energy).  That's because price and wattage 
are the two fixed quantities associated with a solar cell.  The number 
of KWH it generates over its expected lifetime depends on how long it 
keeps functioning (in our case, not long; once the solder loosens, it's 
over).  If a product is brand new, how can you have any idea at all how 
long it will normally last?

But it was the second part that really set off my BS detector.  I'm 
trying to find some other interpretation for what's written here, but 
120 watts per square inch is far more energy than what is contained in 
sunlight.  Maybe you're supposed to concentrate the light with a lens 
first.  Since sunlight has about a kilowatt (1000 W) in every square 
meter (almost 1600 sq. in.), it cannot possibly generate more than _one_ 
watt per square inch, and generally nowhere near that, since at most 10% 
of the energy is converted to electricity.

Bill