Landfill sites are more than repositories for waste – they are long-term sources of a valuable, renewable fuel. As organic material decomposes, it releases landfill gas, primarily methane and carbon dioxide, which can be captured and converted into electricity. What was once considered a risky, unproven venture is now a well-established commercial activity, backed by decades of engineering experience and a clear, repeatable project route.
This article walks through the full journey of a landfill gas electricity generation project – from initial feasibility studies through to long-term operation and maintenance – and explains why careful planning at every stage is essential to maximising commercial return.
“The utilisation of landfill gas for electricity generation is an established commercial activity. The days of risk assessment and uncertainty have long since passed.”
Why Landfill Gas Matters
Landfill gas is generated naturally as organic waste decomposes anaerobically underground. Left unmanaged, it poses environmental and safety risks, including uncontrolled methane emissions – a potent greenhouse gas – and the potential for gas migration. Capturing this gas and using it to generate electricity turns an environmental liability into a revenue-generating asset, while reducing emissions from the site.
The Project Route: From Desk Study to Operation
A successful landfill gas power project follows a logical sequence of stages, each acting as a decision gate before further investment is committed.
1. Desk Study to Evaluate Potential
The process begins with a desk-based evaluation of the site. This establishes the scale of the opportunity by reviewing:
- The quantity of waste in place and the site’s tipping history
- The type and approximate composition of the waste
- The extent and quality of the site’s capping
- The hydrogeological regime, including flood risk
If a site is waterlogged, for example, a full leachate extraction and treatment system may be required before the gas can even be accessed – a cost that must be factored in early. Data gathered at this stage feeds into a mathematical model that projects future gas production, forming the key tool for estimating the site’s power generation potential.
2. Field Data Collection
An on-the-ground survey complements the desk study. Practical factors such as the best route to power lines, the fall of the land, and options for locating the power plant all influence both feasibility and the optimum choice of technology. Experienced engineers can quickly identify site-specific issues that need to be addressed before design work begins.
3. Pumping Trials
A pumping trial is a strongly advisable step before committing to full-scale design. It establishes the current equilibrium gas production rate at specific locations across the site, allowing the accuracy of the desk study’s mathematical model to be verified in the field.
This step matters because actual site conditions can differ from historical records. In some cases, waste has been burned in-situ during or after tipping, meaning the real organic content – and therefore gas potential – may not match what the tipping history suggests.
Historically, some financiers required a full gas extraction system to be run for one or two years before accepting a project as commercially viable. Today, a desk study followed by a pumping trial is considered adequate – saving significant time and preserving the value of the gas resource.
4. Capacity Determination
Deciding on the capacity of the power station is a critical decision gate. Although landfill gas is “free,” maximising return still requires careful risk management. A facility can be sized to capture the full duty available from the gas production curve, or scaled back in a more conservative “play-safe” mode.
For example, a production curve might support a maximum output of 3.5 MW at peak, or be conservatively capped at 2-3 MW to reduce risk. The chart below illustrates how staged capacity (e.g. 1 MW, 2 MW, 3 MW, plus smaller top-up units) can be matched to the rising and falling gas production curve over time.
| Stage | Approximate Capacity | Position on Gas Curve |
|---|---|---|
| Base load | 1 MW | Early/sustained production |
| Mid stage | 2 MW | Rising production |
| Peak stage | 3 MW | Peak production |
| Top-up units | 300-500 kW | Peak and tail-end balancing |
5. System Design
There is no one-size-fits-all design for a landfill gas power system. As engine manufacturers have refined their products to better match market needs, system designers can now tailor solutions – covering gas extraction, gas treatment (where required), engine placement, and electrical connection – to the specific characteristics of each site.
6. Finance
Financing landfill gas projects is no longer the barrier it once was. Given the strong track record of operating systems worldwide, the challenge today is choosing the financing structure best suited to a particular project, rather than proving the concept is viable at all.
7. Procurement
Once finance is confirmed, procurement of components begins. Careful sequencing is essential, as various elements must arrive on site when needed. One commonly underestimated source of delay is arranging the electricity export connection – a step that requires early and continuous attention.
8. Construction and Commissioning
With components procured, the system moves into construction and commissioning – installing gas extraction infrastructure, engines, and electrical connections, and bringing the facility into full operation.
9. Operation and Maintenance
The final, and arguably most important, ongoing element is running the facility at optimum performance. In a commercial power generation operation, every additional percentage point of uptime goes straight to the bottom line.
Operating at 90% availability may be commercially viable – but pushing uptime to 99% can make a significant difference to overall profit margins.
Gas Extraction: The Engineering Backbone
Good gas extraction system design is central to stable, long-term project performance. Key considerations include:
- Flow control – specialised valves allow wellhead calibration by gas quality and flow rate, adjustable to approximately 1 Nm³/hr, enabling fine balancing of the system across the site.
- Water management – both groundwater ingress through well-liners and condensate formation during active extraction must be carefully managed, as water build-up can significantly affect system performance.
Fine-tuned extraction systems allow operators to extend productive gas recovery further into the “back end” of the production curve, extracting more commercial value from a declining resource.
Key Benefits at a Glance
- Proven technology – landfill gas-to-electricity systems have been deployed commercially for more than 15 years across hundreds of sites worldwide
- High reliability – complete facilities can achieve more than 95% availability, with gas pumping and processing equipment reaching up to 99%
- Flexible delivery models – available as turnkey design, manufacture, and installation, or as component supply only
- Integrated finance options – available through affiliated financing arrangements
- Full lifecycle support – from feasibility through to long-term operation and maintenance
Summary
Turning landfill gas into electricity is a mature, well-understood process, but success depends on following a disciplined project route: a thorough desk study, field data collection, a pumping trial to validate assumptions, careful capacity determination, tailored system design, secured finance, timely procurement, quality construction, and disciplined ongoing operation. Each stage acts as a checkpoint that protects the overall investment and ensures the maximum commercial value is extracted from the site’s gas resource.
Organisations with deep, hands-on experience across hundreds of landfill sites – spanning multiple countries and waste types – are best placed to navigate the site-specific pitfalls that inevitably arise, and to deliver a facility that performs reliably for the lifetime of the gas resource.
Get in Touch
If you’re evaluating a landfill site for its electricity generation potential, or looking to improve the performance of an existing gas-to-energy facility, our team can help – from initial feasibility studies through to full turnkey delivery and ongoing operation. Contact us today to discuss your project.