John McGrath’s original “Bible” has now been scanned and shared online. A free PDF version, including dimensional drawings and parts lists for three different gasifier sizes, is available through the Open Gasifier Project.
You don’t need an oil well. You don’t need solar panels on a south-facing roof. You need branches. And the ancient, almost-forgotten technology of wood gasification. In the simplest terms, a wood gasifier is a chemical reactor that turns solid wood into a flammable gas. It does this not by burning the wood, but by cooking it in a low-oxygen environment—a process called pyrolysis. John McGrath’s original “Bible” has now been scanned
The Wood Gasifier Builder’s Bible is not a sacred text. It’s a stack of Xeroxed schematics, hand-drawn diagrams, and notes written in Sharpie on plywood. But it contains a truth that feels almost biblical: You don’t need solar panels on a south-facing roof
Below 20% moisture. How to test? The “crack test.” Hit two pieces together. Dry wood makes a sharp, ringing crack. Wet wood thuds. In the simplest terms, a wood gasifier is