what a lot of greenhouse gas

I was asked the other day to confirm the figure that around 12% of Hong Kong’s greenhouse gas emissions are caused by methane (which is principally generated in landfills from rotting food). It’s important because the bokashi composting system we have been introducing in schools does not generate methane, thus reducing greenhouse gas emissions.

I’d come across the 12% figure many times, but rather than quoting it again, I went back to the government’s own figures. These can be found on the EPD website http://www.epd.gov.hk/epd/english/environmentinhk/air/data/files/GHG_Inventory_Table_1990_2006.pdf . The second table contains the greenhouse gas contribution from methane taking into account that it is around 21 times more potent as a greenhouse gas than carbon dioxide. In the last two years, around 5200 kilotonnes of CO2 equivalent were emitted as methane, close to 12% of Hong Kong’s total greenhouse gas emissions.

Food waste is a problem in Hong Kong as it makes up around 30% of the total amount of waste going to landfill. The problem appeared as a CNN article last year. http://edition.cnn.com/2007/WORLD/asiapcf/09/24/food.leftovers/index.html