Lean-burn efficiency, methane slip and the measurement gap
Lean-burn natural gas engines are widely used across North America to power upstream and midstream equipment such as compressors, generators and pump systems. Operators rely on them because they deliver strong thermal efficiency, reduce fuel consumption and can lower certain criteria pollutants compared to other combustion approaches.
That efficiency comes with a tradeoff. Running lean can increase the likelihood that a portion of methane passes through the engine unburned. This methane slip can be small in volume but significant in climate impact.
For energy producers, this is not only a compliance challenge. It is a measurement and decision-making challenge as methane regulations tighten. More frequent, defensible methane slip quantification helps operators reduce emissions while preparing for current and emerging requirements.
A field-ready approach to measuring methane slip
Onterris partnered with the BC Oil and Gas Research Society (BC OGRIS) to test an alternative approach for quantifying methane slip directly at the source. The team evaluated the SEMTECH® Hi-Flow 2, a portable analyzer designed to measure methane leaks in real time under operating conditions.
The goal was to demonstrate that real-time methane quantification can reach FTIR-level performance while lowering cost and reducing operational effort. Hi-Flow 2 offered a more accessible field footprint than traditional FTIR deployments, with estimated deployment costs of roughly 20% to 50% of the cost per engine.
That cost profile matters when an operator wants to move from occasional measurement to a repeatable program.
From pilot to fleet-wide deployment
Phase 1 compared Hi-Flow 2 to FTIR on a limited number of lean-burn engines. Results showed comparable accuracy, while also revealing practical constraints to address before scaling. The team saw intermittent moisture interference, the sample size limited confidence, and the setup did not yet include mass-emission calculations.
The team expanded the design, improved the measurement framework and prepared for a broader test that reflected how measurement programs run in the real world.
We designed the study around what a compliance team actually needs, reliable numbers, fast execution and a method a technician can deploy safely across a working fleet without disrupting operations.
Antonios Tasaglou, Emerging Technology Manager, Onterris
Phase 2 expanded testing across 32 engines at 19 leases in British Columbia’s Peace River region. The results confirmed the central premise: real-time methane monitoring can work at scale and it can support fleet-wide decision-making.
The team completed 96 tests with zero failures. A single technician could collect reliable measurements in under 15 minutes per engine. Those time and reliability metrics shift what is feasible for routine measurement, especially when operators manage dispersed assets and compressed maintenance windows.
The results also reinforced an operational insight many teams suspect, that lean-burn engines emitted about twice the methane of rich-burn units in the tested set. That type of comparison supports better prioritization, whether the next step is targeted maintenance, tuning, replacement planning or deeper investigation.
Accuracy that supports compliance decisions, not just screening
Field speed only matters if the results support defensible decisions. The study showed that operators can achieve Tier-3 accuracy, within 9%, by pairing Hi-Flow 2 measurements with a compact oxygen sensor and fuel-flow data. This approach strengthens the pathway from field measurement to mass-emissions calculations that regulatory and internal reporting teams can use.
This reduces the gap between what teams can measure and what regulations increasingly require. It also creates a practical option for frequent measurement without defaulting to the most complex and costly deployment every time.
The next era of measurement is real-time
As methane expectations continue to rise across North America, fast, repeatable and defensible field measurement is becoming central to regulatory readiness and credible emissions performance. The tools and methods are available today, making real-time methane quantification practical at fleet scale, without the cost and complexity of traditional approaches. With better visibility into methane slip, operators can focus on the highest-impact actions, verify outcomes and demonstrate performance with confidence. The result is methane management that fits operational realities and delivers meaningful emissions reductions.