Methane emissions from Icelandic landfills - A comparison between measured and modelled emissions

• Published in: Waste Management
• Main Authors: Scheutz, C., Kjeld, A., Fredenslund, A.M.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2022
• Subjects: Tracer gas dispersion; Methane oxidation; Landfill gas generation; Gas collection; FOD model; /dk/atira/pure/sustainabledevelopmentgoals/climate_action; name=SDG 13 - Climate Action; Álfsnes; Gufunes; Iceland
• Online Access: https://orbit.dtu.dk/en/publications/831f312c-8823-4606-adc8-8dfded4cecef; https://doi.org/10.1016/j.wasman.2021.12.028; https://backend.orbit.dtu.dk/ws/files/266754260/1_s2.0_S0956053X21006735_main.pdf

This study compares methane (CH 4 ) emissions from five Icelandic landfills, quantified using tracer gas dispersion to modelled emission rates using the IPCC FOD model. The average CH 4 emission rates measured from the investigated landfills were 475.4 kg CH 4 h −1 (Álfsnes landfill), 32.5 kg CH 4 h −1 (Fíflholt), 40.8 kg CH 4 h −1 (Gufunes), 9.8 kg CH 4 h −1 (Kirkjuferjuhjáleiga) and 78.4 kg CH 4 h −1 (Stekkjarvík). At three of the landfills (Álfsnes, Fíflholt and Kirkjuferjuhjáleiga), the modelled emission was higher than the measured emission by factors ranging from 1.1 to 4.8, neglecting any CH 4 oxidation in the cover soils. Even though CH 4 oxidation might play a role at some of the investigated landfills, and thus reduce the gap between modelled and measured emissions, it is likely that the model overestimated CH 4 generation due to uncertainties in input model parameters. Assuming that the measured emissions at the five landfills are representative of all the waste disposed in Iceland from 2007 to 2016, the measured emission should be extrapolated to 817 kg CH 4 h −1 , which is relatively close to the modelled national emission of 936 kg CH 4 h −1 in 2017. This study showed that the application of the IPCC FOD model at national level is appropriate for estimating landfill CH 4 emissions in Iceland. CH 4 emissions from landfills in Iceland can be reduced by expanding or implementing gas collection or biocover systems for optimised microbial oxidation.