Co-generation potentials of municipal solid waste landfills in Serbia

Waste management in the Republic of Serbia is based on landfilling. As a result of such year-long practice, a huge number of municipal waste landfills has been created where landfill gas has been generated. Landfill gas, which is essentially methane (50-55%) and carbon dioxide (40-45%) (both GHGs), has a great environmental impact which can be reduced by using landfill gas in cogeneration plants to produce energy. The aim of this paper is to determine economic and environmental benefits from such energy production. For that purpose, the database of cogeneration potentials (CP) of 51 landfills in the Republic of Serbia (RS) was created. Amount of landfill gas generated at each municipal landfill was calculated by applying a first order decay equation which requires the data about solid waste production and composition and about some landfill characteristics. For all landfills, which have over 100,000 m3 each, a techno-economic analysis about building a CHP plant was conducted. The results have shown, that the total investment in 14 CHP plants with payback period of less than 7 years amounts € 11,721,288. The total nominal power of these plants is 7 MW of electrical power and 7.9 MW of thermal power, and an average payback period is about 61 months. In addition, using landfill biogas as energy source in proposed plants would reduce methane emission for 161,000 tons of CO2 equivalent per year. [Projekat Ministarstva nauke Republike Srbije, br. III 42013: Research of cogeneration potential of municipal and industrial energy power plant in Republic of Serbia and opportunities for rehabilitation of existing and construction of new cogeneration plants