According to IPCC, the waste sector (wastewater + solid waste management) accounts for 2.7% of global Greenhouse gas (GHG) emissions. However, this does not reflect the whole truth as IPCC calculatations only take into account end-of-pipe waste management strategies neglecting the potencial of reducing, re-using or recycling waste (which applies mainly for solid waste management but also for innovative sanitation tecnologies such as anaerobic digestion and ecosan approaches).
For this reason it is important to investigate the contribution of the waste sector to GHG emissions and integrate the mitigation potential in waste management. Besides many interesting papers presented at conferences worldwide about the importance of an integrated organic waste and wastewater management and its influence on climate change, GHG emissions and the potential of CDM-projects in this field, instruments are needed that show the potential of emission reduction in the waste sector.
One of those instruments available is the recently published “Tool for calculating Greenhouse gases in solid waste management (SWM-GHG Calculator)“. The SWM-GHG Calculator was developed by IFEU Institute and sponsored by KfW Development Bank in cooperation with GTZ. It is based on Excel as a common spreadsheet application and accompanied by a user manual. By help of the calculator waste management strategies can be compared by calculating the GHG emissions of different waste fractions over their whole life cycle following the Life Cycle Assessment (LCA) approach. It does however not provide an in-depth LCA and is not suited for calculating the anticipated quantity of certified emission reductions in the CDM-framework.
More tools that demonstrate the relationship between sanitation and climate change are definitely needed.
See also: Website of the SWM-GHG Calculator (in German).