While it’s attractive to think that PG&E and California will be doing something to generate clean and safe power using renewable sources and without toxic waste, I’m forced to question the use to which they plan to put this 12.5 acres of land. As appealing as 800 MW of power is, the problem is that these figures are “at it’s peak” which is approximately 3 hours of the day (11 AM to 1 PM local time), for less than 1 month of the year (Summer). And the claim that this solar farm “will power 239,000 annually” strains credibility. It’s pure number crunching and statistics.
If you figure that it will operate only for 8 hours a day, PG&Es claim turns in to something closer to “717,000 homes for 8 hours a day.” Of course, the number changes based on how many hours a day the farms can operate, and also their exact power output at the various parts of the day (they’ll always support more usage at 12 PM noon than they will at either 10 AM or 2 PM). And since Solar Farms will only provide power during daylight hours, the need for power at night (while potentially less than day time demands) still needs to be met.
What’s curious is that PG&E is building one of their solar farms using technology produced by Optisolar which is eerily similar to Nanosolar. As far as I can tell, they’re doing approximately the same thing. The technique has to be different. Nanosolar, also a Bay Area company, has already built it’s 1 GigaWatt Solar Panel production facility in San Jose and boasts having it’s entire inventory sold for the forseeable future. Likewise, Optisolar’s website has a number of claims of large scale municipal projects to provide solar farms that will power communities in areas around the North Americas.
I wonder why PG&E went with Optisolar, when their technology does not talk about how to deploy this on to the wasted space above homes and commercial buildings and yet Nanosolar offers everything Optisolar does but also offers thin, cut to form, solar panels that can be placed anywhere. On top of vehicles, on top of homes and on top of commercial buildings. 12.5 Acres of land is a lot of space. But if we could convert 20 acres of residential and commercial real estate in to solar farms, we’d provide shade** and generate energy at the same time. (** Granted that shade is not necessarily what we want in the cold North.)
The other curious thing that comes to mind: Who will window wash these solar farms? Mineral accumulation from rainfall and dew will impact power production no matter how you slice it. Someone has to upkeep the photovoltaic windows. Now is the time to invest in Windex 
Edit: Discovered that a bunch of links had been replaced by some kind of privacy javascript. Fixed links.
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