Solar C³ities is an international platform with the intention of providing an open-source virtual Hackspace for "Biogas Innoventors and Practitioners" and training for all those researching, developing and deploying sustainable solutions for flourishing societies.
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I know... I've had some exchanges with a couple of these guys. I made a post about it on facebook. Will put the links here.
NASA was doing it way before. But the commercial guys still cost thousands of dollars. I challenge people to do it cheaply... :)