This page is intented to provide you links to various other websites where additional information can be found.
It also contains references for the figures/calculations found on the product pages of the OTGL (biogas production, ...).
As too mentioned in the product pages, many additional info can also be found at the AT CoLib; this offline wiki can be downloaded from the HealingWeb website. Make sure you read the articles called "autonomous houses and neighborhoods" and "green living" therein. Most additional info is available at the appropriate pages of the AT CoLib (articles "Wood gas as fuel", "Biogas as fuel", "Wind energy conversion system", "Solar energy conversion system", "Thermal energy conversion system", "Hydro energy conversion system", "Biofuel", "Biomass", ... and pages linked from those pages. Note that the Appropedia articles which are similarly named as those at the AT CoLib are subject to change though (unlike the offline AT CoLib).
Downloadable magazines on biogas and other renewable energy generators:
More info on wood gas and biogas:
http://www.drtlud.com/resources/ (Biomass Energy Foundation materials)
More info on wind turbines:
The Prepper Groups Meet-up web page (preppergroups.com)
Chris Martenson's Resilient Life Groups Page