Frank Aragona just posted two podcasts on his Agroinnovations web site that cover on-farm biodiesel production, and the thinking and model behind Farm Hack and open source hardware.
They can be found here http://agroinnovations.com/podcast/2014/05/06/episode-139-on-farm-biodie... (link is external)
and
Here http://agroinnovations.com/podcast/2014/05/20/episode-140-farm-hack/ (link is external)
Frank's other podcasts are terrific resource and I highly recommend checking them out! http://agroinnovations.com/ (link is external)