The Moderate or Intense Low oxygen Dilution (MILD) combustion regime has proven to be particularly suitable for Low Calorific Value (LCV) fuels, because the volumetric reactions are sustained by the hot medium above the self-ignition temperature. Those fuels are produced by biomass gasification, using the excreta of animals in bio-digesters, vented from coalmines or as by-products in chemical processes. These fuels can be damaging to the environment and burning them adds value and help reducing the need for fossil fuels. MILD combustion of methane diluted with inert gases (CO2 or N2), which may be referred to as biogas, is analysed in a controlled experimental environment that emulates MILD conditions. A Jet in Hot Coflow (JHC) burner is used in these experiments. The effects of inert gas addition to the fuel stream on pollutant emissions such as Soot, CO and NOx are presented and analysed. It was observed that combining MILD conditions and fuel dilution resulted in a very efficient method to reduce soot formation and NOx. It was found that a high fuel dilution and low coflow oxygen level may lead to high emission of CO, under the conditions of the JHC burner.