UK – Garden food waste digesters help to reduce carbon footprint

Centralised treatment of food waste using methods such as in-vessel composting or anaerobic digestion can cause more greenhouse gases than household treatments using Food Waste Digesters (FWDs), says an environmental study.



MRW reports that the study titled Comparison of Greenhouse Gas Emissions from the Centralised and Household Treatments of Food Waste found that centralised treatment of food waste produces between 10 and 40 times more CO2 emissions than garden food waste digesters.



Speaking to MRW environmental consultant Dr Alan Knipe who wrote the study said: "The Government is favouring anaerobic digestion as a method to treat food waste because they can also get electricity out of it. But when dustcarts collect this food waste from households they are producing harmful greenhouse emissions that we can avoid.



"It is an expensive method, dirty and dangerous (collecting food waste by dustcarts). If each household had a food waste digester it will bring massive savings in reducing carbon footprint."



However, Knipe did acknowledge that not everybody could have access to food waste digesters particularly those who live in flats.



The study showed that the major contribution to the anthropogenic (man-made) greenhouse gas emissions for the centralised approach arises from the day-to-day operations of the dustcarts and the treatment plant. He found that the total anthropogenic greenhouse gas emissions for the centralised approach range from about 50 to 214kg of CO2 equivalent per tonne of food waste. By contrast, household treatment generates around 5kg CO2 equivalent per tonne of food waste.