Ball David, Eichenlaub Nathan, Lashgari Ali
Project Canary, Denver, CO 80202, USA.
Sensors (Basel). 2025 Apr 29;25(9):2801. doi: 10.3390/s25092801.
Quantifying methane emissions from facilities with complex emissions profiles can present a substantial challenge. Real-world emission scenarios can involve dynamic operational background emissions and temporally overlapping asynchronous emission events with varying rates from multiple sources. Previous studies have involved simpler testing setups, often with synchronous emission sources and constant rates. This work is among the first to assess the performance of continuous monitoring systems (CMSs) under dynamic, overlapping emission scenarios with time-varying baselines. The data were collected as part of a novel single-blind controlled release study, where release sources and emission rates are not disclosed during the testing period. Several error metrics are defined and evaluated across a range of relevant averaging times, demonstrating that despite significant error variance in short-duration estimates, the low bias of the system results in substantially improved emission estimates when aggregated to longer timescales. Over the 4-week duration of this study, 700 kg of methane was released by the testing center, while the estimated quantity shows a final mass of 673 kg, an underestimation by 27 kg (4%). These results demonstrate that advanced CMSs can accurately quantify cumulative site-level emissions in complex scenarios, highlighting their potential for enhanced future emissions monitoring and regulatory applications in the oil and gas sector.
对具有复杂排放特征的设施的甲烷排放进行量化可能是一项重大挑战。实际排放情景可能涉及动态运行背景排放以及来自多个源的不同速率的时间重叠异步排放事件。以往的研究涉及更简单的测试设置，通常具有同步排放源和恒定速率。这项工作是首批评估连续监测系统（CMS）在具有随时间变化基线的动态、重叠排放情景下性能的研究之一。数据是作为一项新颖的单盲控制释放研究的一部分收集的，在测试期间不披露释放源和排放速率。定义并评估了一系列相关平均时间内的几个误差指标，结果表明，尽管短期估计中存在显著的误差方差，但当汇总到更长的时间尺度时，系统的低偏差会使排放估计有显著改善。在本研究的4周期间，测试中心释放了700千克甲烷，而估计量显示最终质量为673千克，低估了27千克（4%）。这些结果表明，先进的CMS能够在复杂情景中准确量化累积的场地级排放，凸显了其在未来石油和天然气行业排放监测及监管应用方面的潜力。
