Well, whoever wrote this press release isn't too knowledgeable about what they're writing about.
The contaminant of concern in biogas is siloxane, not silica.
The statement "It is uniquely able to generate electricity from highly contaminated biogas." is puzzling, when David Sastry admitted on the Freedom Motors blog that they have never actually run one of their engines on biogas.
It's also somewhat amusing that if you want information, you're supposed to write a snail mail or make a telephone call. I'm surprised that they don't list Telex or request telegraphs. Perhaps Paul wrote this himself?
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