This is an amazing subject that I am finally getting my head wrapped around. Honestly, the more I read and learn about this, the more I am shocked that this technology is not more widespread. Let me start with a few definitions first:
Gasification: This is a process of converting organic materials into carbon monoxide (CO), hydrogen (H), carbon dioxide (CO2), and methane (CH4) through really high temperatures without combustion (burning). Wikipedia has a pretty good article on gasification here.
Syngas (aka Synthesis Gas or "Producer Gas"): This is the gas that results from Gasification. It mainly consists of carbon monoxide and hydrogen.
Biomass Gasification: Another way of saying Gasification that is fueled by organic (carbonaceous) materials like wood and other waste products.
Fischer-Tropsch Process: This is a set of chemical reactions that will convert a gaseous mixture of Syngas into a liquid form of synthetic fuel that can be used as a replacement for petroleum-derived fuel. While I am mentioning it here just because it is really cool, the video below shows an engine running on only the gaseous form of Syngas.
A Brief History
This technology is over 180 years old! Many towns were fueled with the gasification method until the advent of widespread electricity. During the World Wars, it is estimated that close to a million vehicles were run by gasification when petroleum-derived fuels were rationed. FEMA (yeah, the US Federal Emergency Management Agency) published a book in 1989 that outlines how to build a gasification generator in an emergency if petroleum-based fuels are not available.
Obviously, there are some downsides to this or else it would be everywhere. They take a while to warm up. It is not as cheap for commercial enterprises. It takes a while to cool down. Produces wood tar which can dirty an engine.
The advantages, especially for a small-scale home producer, are many. Gasification can run internal-combustion engines (like a generator to power the house!). It can be pretty easily made using common materials. It can run on any organic waste products and wood. It can be combined with a water heater for dual purpose.
So let me show you a Biomass Gasification Generator in action:
Here is a set of really well done videos that explains a lot about Gasification: