Wood Gas / Producer Gas
A gasifier heats biomass under controlled oxygen conditions, producing a combustible gas mixture.
- Complexity
- High
- Best suited for
- Stationary power where dry biomass is abundant and professional equipment is available
- Scale
- Farm · Commercial
Overview
Wood gas — also called producer gas or syngas — is made by heating biomass with a restricted supply of oxygen so it breaks down into a combustible gas rather than burning completely.
It powered hundreds of thousands of vehicles during fuel shortages in the 1940s. It remains technically viable, and it is also the most hazardous technology on this site for improvised construction.
Key consideration
Producer gas can contain significant carbon monoxide and requires professionally designed equipment, ventilation, filtration and monitoring.
Inputs & outputs
Feedstocks in
- Wood
- Wood chips
- Dry biomass
Fuel out
- Combustible producer gas (carbon monoxide, hydrogen, methane)
How it works
- 1Dry wood or biomass
- 2Gasifier
- 3Producer gas
- 4Cooling
- 5Filtration
- 6Engine
Conceptual diagram. Real systems include control, monitoring and safety equipment at every stage.
What can it power?
Equipment categories
- Fuel drying and sizing
- Gasifier reactor
- Cyclone and particulate removal
- Gas cooling
- Tar and fine filtration
- Carbon monoxide detection and alarms
- Engine air/gas mixing and control
- Ash and condensate handling
Described at a category level. Equipment should be professionally specified, certified and installed.
Cost profile
Startup
Medium–High
Operating
Medium
Feedstock
Free to low-cost
Relative categories only. Real costs depend heavily on scale, equipment and local conditions.
Efficiency
Producer gas has a low energy density compared with natural gas, so an engine running on it typically produces substantially less power than on its design fuel. Gas cleanup quality has a direct effect on engine life.
Pros & limitations
Advantages
- Feedstock is often free and locally abundant
- Historically proven under real-world conditions
- Does not depend on liquid fuel supply chains
- Works well for continuous stationary loads
Limitations
- Serious carbon monoxide hazard
- Significant power derating on engines
- Tar and particulate cleanup is the hardest engineering problem
- Labour intensive — constant fuel handling and maintenance
Vehicle compatibility
Never assume compatibility. Verify with the engine or equipment manufacturer before use.
Storage
Producer gas is generally made on demand rather than stored. Storing it introduces carbon monoxide and explosion risks that are outside the scope of amateur systems.
Safety & Regulations
Safety considerations
- Carbon monoxide is colourless, odourless and lethal — detection is mandatory
- Never operate a gasifier in an enclosed or attached space
- Hot surfaces, flare-back and condensate hazards
- Tar condensate is toxic and requires proper disposal
Legal & regulatory
- Air-quality and combustion regulations
- Fire code and clearance requirements
- Road-use restrictions for mobile gasifier installations
- Occupational safety requirements for commercial use
Requirements vary by jurisdiction and fuel type. Verify applicable rules before producing, storing, selling or using fuel. Use certified equipment and qualified professionals.