Total methane loss from biogas plants, determined by tracer dispersion measurements

Methane losses from biogas plants are problematic, since methane emitted into the atmosphere contributes to global warming, and any losses may thus reduce the environmental benefits of biogas production. A tracer gas dispersion method was used to measure total methane emissions from seven biogas plants, and more measurement campaigns are planned.

Emissions varied between 1.3 and 13.4 (kg CH4 h-1), and losses expressed in percentages of production varied between 0.3 and 6.4%. The tracer gas dispersion method was found to be useful in quantifying total methane emissions from biogas plants, whereas the detection and quantification of individual leaks at the plants require other methods.