Wasting the Nation.indd - Groundwork

Chapter 6: Down at the dumpscomposting restores a part of the cycle of life. As noted, Bisasar Road’s managementis using ground up garden waste as landfill cover and, in doing so, contributing tofuture LFG generation. Composting decomposes organic matter aerobically and sodoes not generate methane emissions or leachate. City scale composting, however,does not generally include kitchen wastes for public health reasons. A biogas digestercan accommodate a mix of garden and wet wastes. It uses an anaerobic process whichdestroys pathogens and produces methane gas on the one hand and compost on theother. Assuming that the wet waste is not contaminated by other wastes – requiringthat it is separated at source – the gas from a digester is fairly pure. Using it for energygeneration therefore avoids most of the problems associated with LFG. Emissions arelargely carbon dioxide but this is mostly off-set by the carbon absorbed during theplants’ growth so it provides a genuine low carbon technology.LFG wells have not been developed at Buffelsdraai yet because it is not yet producingenough to give an economic return. If the bulk of organic wastes are intercepted beforelandfill, it will be a largely dry landfill. The landfill will still be noisy, dusty and strewnwith litter, but neighbours will not have to breathe toxic LFGs or the toxic emissionsfrom burning LFGs.The costs of LFG capture and power generation are covered by two revenue streams:the sale of the electricity and of ‘certified emissions reductions’ (CERs). CERs are partof the global trade in carbon brought into being by the Kyoto Protocol. Southerncountries can access this trade through the Cleaner Development Mechanism (CDM).With the support of the World Bank, DSW persuaded eThekwini Council thatCDM revenues would make the project profitable in the short term at a carbon priceof $3.95/tonne. The returns now look better than ever. This year’s 27.5% hike inelectricity prices will be followed by similar rises in the next two years and CERs arenow trading at close to E20 ($30) on European markets – although this is a highlyvolatile market. Moreover, DSW got in before the global price of energy projects wentthrough the roof. Capital costs on equivalent projects are now considerably higher. Forthe council, which takes the profits, it looks like a sweet deal. DSW managers pointout that they can still get carbon credits for composting or for a biogas digester. Theprospect of a dry dump at Buffelsdraai is not therefore a problem, assuming that thecarbon trading market is extended beyond 2012 through the current round of climatechange negotiations. Besides, with the rising electricity price, CDM may become justthe cherry on the top, according to Parkins.Wasting the Nation - groundWork - 143 -