Technological innovations for the ecological transition: monitoring methane emissions in landfills using drones

By the year 2030, the European Union aims to achieve 65% separate waste collection, which means that 35% of waste will have to be disposed in landfills. Solid waste disposal is therefore a necessary part of the transition to a fully sustainable economy, while respecting the climate neutrality targets set. However, landfills are a significant source of CH4 emissions into the atmosphere, and flux monitoring is often carried out using the dynamic or static chamber method. Although the method is currently the standard technique for estimating the flux of trace gases contained in non methane volatile organic compounds (NMVOCs), it has limitations that are increasingly highlighted and discussed in scientific literature. Some of these limitations can potentially be surpassed or mitigated using UAV platforms (Unmanned Aerial Vehicle, commonly referred to as 'drones'), by equipping them with appropriate sensors. This paper intends to provide an overview of UAV-based methods that can be used to estimate CH4 fluxes from a landfill, how data are acquired and processed, and the different field experiences in the field. Recent technological developments in instrumentation and the results achieved by each method are highlighted, along with their advantages and disadvantages. Finally, an innovative drone based CH4 flux quantification methodology is presented, illustrating the results obtained from several tests carried out in controlled release tests.