Application of Long Endurance UAS for Top-Down Methane Emission Measurements of Oil and Gas Facilities in an Offshore Environment

Abstract

Oil & gas (O&G) operators are increasingly focused on decarbonization and reaching net-zero carbon emissions. The O&G industry seeks to minimise methane emissions. Verification of estimated emissions using top down measurement methods represents a critical component of this effort. A novel approach to operationalizing top-down emissions surveys was developed and demonstrated, leveraging expertise in unmanned vehicle application, innovative methane emissions measurement technology, and an O&G industry collaborator. The inspection technique utilizes a fixed-wing unmanned aircraft to perform a remote offshore asset inspection while safely launching and recovering onshore. This method enables the collection of many tens of thousands individual point methane concentration measurements and affords the ability to resolve facility-level methane emissions and in conjunction with appropriate environmental conditions information, derive an accurate emission rate for an individual asset, while accounting for background fluctuation and potential upwind sources.The unmanned aircraft does not require any crew or equipment to be taken offshore or make modifications to the asset, thus allowing inspections to be performed with minimum impact to facility operations. This work overcame significant regulatory hurdles to fly long distance unmanned aircraft in congested airspace, developed detailed operational procedures and demonstrated the safety of the technique to both the O&G and aviation community, and the effectiveness of the measurement technology. The work demonstrated the suitability of the technique for operationalisation for routine measurement programmes.