Technologies
The right technology for the right project.
Biomass and waste-to-energy conversion spans a wide range of technologies — each with different feedstock requirements, capital profiles, and operating characteristics. Understanding the trade-offs is the foundation of every successful project.
Technology selection is where projects succeed or fail.
The Australian market has seen too many projects stall or fail because the wrong technology was chosen — often driven by vendor enthusiasm rather than rigorous analysis. At Ridout Holdings, technology selection is always feedstock-first: we start with what you have, then identify the conversion pathways that are genuinely suited to it. Our independence from vendors means we have no incentive to favour one technology over another.
The technologies described below represent the pathways we work with most frequently in the Australian context. Each section outlines how the technology works, what feedstocks it suits, its typical scale range, and the key considerations for Australian projects.
Direct Combustion
The most proven pathway for large-scale biomass power generation.
Direct combustion — burning biomass to produce steam, which drives a turbine to generate electricity — is the most commercially mature biomass-to-energy technology. It is well understood, widely deployed, and supported by a deep pool of engineering expertise and equipment suppliers.
How it works
Biomass feedstock is burned in a boiler to produce high-pressure steam. The steam drives a turbine connected to a generator, producing electricity. Waste heat from the process can be captured for industrial process heat or district heating, significantly improving overall efficiency. Modern systems use advanced combustion controls and emissions management to meet Australian environmental standards.
Suitable feedstocks
- Sugarcane bagasse
- Wheat and cereal straw
- Forestry and sawmill residues
- Wood waste and demolition timber
- Energy crops (e.g. mallee, eucalyptus)
Typical scale
Typically 1 MW to 50+ MW electrical output. Most cost-effective at larger scales (5 MW+).
Key considerations
Direct combustion systems require consistent, high-volume feedstock supply. Feedstock moisture content significantly affects efficiency — drying may be required. Capital costs are relatively high but technology risk is low. Well-suited to co-location with existing industrial operations (sugar mills, sawmills, paper mills) that generate biomass as a by-product.
Australian context
Australia has a long history of bagasse combustion in the sugar industry. There is growing interest in dedicated biomass power stations using forestry residues and agricultural straw, particularly in Queensland and NSW.
Gasification
Flexible, efficient conversion of dry biomass to syngas.
Gasification converts dry biomass into a combustible gas mixture (syngas) through partial oxidation at high temperatures. The syngas can be used to generate electricity via a gas engine or turbine, or further processed into liquid fuels or chemicals.
How it works
Biomass is fed into a gasifier where it is partially oxidised at temperatures of 700–1,200°C in a controlled, oxygen-limited environment. This produces syngas — a mixture of hydrogen, carbon monoxide, methane, and other gases. The syngas is cleaned and cooled before being used in a gas engine or turbine to generate electricity. Combined heat and power (CHP) configurations capture waste heat for additional efficiency.
Suitable feedstocks
- Wood chips and pellets
- Forestry residues
- Agricultural residues (low moisture)
- Demolition timber
- Charcoal and biochar
Typical scale
Typically 100 kW to 10 MW. Particularly well-suited to smaller, distributed applications.
Key considerations
Gasification requires low-moisture feedstock (typically <20% moisture content). Syngas cleaning is critical — tar management is a key technical challenge. Technology risk is higher than direct combustion, and vendor selection requires careful due diligence. Well-suited to remote and off-grid applications where diesel displacement is the primary value driver.
Australian context
Gasification is attracting significant interest in regional and remote Australia as a diesel replacement technology. Several projects are operating or under development in the Northern Territory, Western Australia, and Queensland, targeting mining operations and remote communities.
Anaerobic Digestion
Proven biogas production from wet organic waste.
Anaerobic digestion (AD) uses microorganisms to break down wet organic material in the absence of oxygen, producing biogas (primarily methane) and a nutrient-rich digestate. It is the dominant technology for wet organic waste streams and is well-established globally.
How it works
Organic feedstock is fed into a sealed digester vessel where bacteria break it down over a period of weeks. The process produces biogas — typically 55–70% methane — which can be used directly in a gas engine to generate electricity and heat, upgraded to biomethane for injection into the gas grid, or used as vehicle fuel. The solid and liquid digestate by-products are valuable as agricultural fertilisers.
Suitable feedstocks
- Food processing waste
- Municipal food waste
- Livestock effluent (piggeries, dairies, feedlots)
- Abattoir waste
- Sewage sludge
- Crop residues (high moisture)
Typical scale
Highly scalable — from small farm-scale systems (50 kW) to large centralised facilities (5+ MW). Scale is primarily determined by feedstock availability.
Key considerations
AD systems are sensitive to feedstock composition and consistency. Feedstock pre-treatment may be required. Digestate management and land application logistics need to be planned carefully. Odour management is important for community acceptance. The technology is well-proven and carries relatively low technical risk.
Australian context
AD is well-established in Australia's piggery and dairy sectors. There is growing interest in food waste AD, driven by state-based organic waste diversion targets and the increasing cost of landfill. Several large food waste AD facilities are operating or under development in Victoria, NSW, and Queensland.
Pyrolysis
Thermal conversion producing biochar, bio-oil, and syngas.
Pyrolysis thermally decomposes biomass in the absence of oxygen, producing three co-products: biochar (a solid carbon-rich material), bio-oil (a liquid fuel), and syngas. The relative proportions of each product can be tuned by adjusting process temperature and residence time.
How it works
Biomass is heated to 300–700°C in an oxygen-free environment. Slow pyrolysis (lower temperatures, longer residence times) maximises biochar production. Fast pyrolysis (higher temperatures, shorter residence times) maximises bio-oil yield. The syngas produced can be used to provide process heat, making the system energy self-sufficient. Biochar has significant value as a soil amendment and carbon sequestration product.
Suitable feedstocks
- Wood waste and forestry residues
- Agricultural residues
- Sewage sludge (with pre-drying)
- Manures (with pre-drying)
- Municipal solid waste (selected fractions)
Typical scale
Typically 500 kW to 5 MW thermal. Commercial-scale pyrolysis is less mature than combustion or AD.
Key considerations
Pyrolysis technology is less commercially mature than direct combustion or AD, and vendor due diligence is particularly important. The biochar market in Australia is developing but not yet deep. Bio-oil quality and end-use markets need careful assessment. The carbon sequestration value of biochar may provide additional revenue under Australian carbon markets.
Australian context
Pyrolysis is attracting growing interest in Australia, particularly for its biochar co-product and potential carbon credit revenue. Several demonstration and early commercial projects are operating, primarily in the agricultural sector.
Landfill Gas Capture
Turning unavoidable methane emissions into clean electricity.
Landfill gas (LFG) — produced by the decomposition of organic material in landfills — is primarily methane, a potent greenhouse gas. Capturing and combusting LFG to generate electricity converts a significant emissions liability into a renewable energy asset.
How it works
A network of extraction wells is drilled into the landfill body and connected to a collection header. The gas is drawn to a central processing facility where it is cleaned and dewatered before being used in gas engines to generate electricity. LFG projects can generate Australian Carbon Credit Units (ACCUs) under the Emissions Reduction Fund, providing an additional revenue stream.
Suitable feedstocks
- Municipal solid waste landfills (active and closed)
- Industrial waste landfills with high organic content
Typical scale
Typically 500 kW to 5 MW, depending on landfill size and age. Output declines over time as the landfill ages.
Key considerations
LFG projects require a landfill with sufficient organic waste mass and remaining gas generation potential. Gas quality and quantity need to be assessed through field testing. Regulatory requirements for LFG capture vary by state. Projects on closed landfills require careful assessment of site access and infrastructure.
Australian context
LFG capture is well-established in Australia, with projects operating at major landfills in all states. Many councils operate LFG projects as part of their waste management and sustainability strategies. The Emissions Reduction Fund has been an important revenue driver for Australian LFG projects.
Technology selection
How we approach technology selection
Every project is different. The right technology depends on your feedstock, your scale, your location, your risk appetite, and your financial objectives. Our technology selection process is rigorous, independent, and always starts with the feedstock.
Feedstock characterisation
We start by understanding your feedstock in detail — quantity, quality, moisture content, seasonal variability, and long-term availability. This determines which conversion pathways are technically feasible.
Pathway screening
We screen all technically feasible conversion pathways against your project objectives — scale, capital budget, risk tolerance, and desired outputs (electricity, heat, fuel, biochar).
Shortlist and deep-dive
We develop a shortlist of two or three preferred pathways and conduct a deeper analysis of each, including indicative capital and operating costs, performance benchmarks, and Australian vendor landscape.
Recommendation
We provide a clear, evidence-based recommendation with a full rationale — including the trade-offs we considered and why we reached our conclusion.
Need help selecting the right technology?
Independent technology advice is one of our core services. We have no vendor relationships and no incentive to favour one technology over another — just the expertise to help you make the right choice.