Possibilities of Using Landfill Biogas for Heating Agricultural Greenhouses in Crete-Greece

Abstract

Biogas is currently produced in Crete-Greece from the two existing landfills in the island, as well as from the sewage treatment plants in Chania and Heraklion. Biogas produced in the two treatment plants is already used for co-generation of heat and power. However, since the quantities of landfills biogas and its energy content are significant, it can be used in the future either for heat production or for heat and power generation. Generated power can be fed into the grid and the produced heat can be used from a heat consumer. Since large heat consumers are not located nearby the existing landfills, there is the possibility for the creation of agricultural greenhouses in the surrounding agricultural areas which can utilize the generated heat. Landfill in Heraklion has an average biogas production of 1.43x107 NM3/year, almost five times higher than the landfill in Chania and the totally recoverable biogas from the two landfills can generate 16.73 GWh/year of electricity, in the case of a CHP plant, and enough heat for heating 15.4 hectares of modern greenhouses. In the case of direct heat generation, recoverable landfill biogas can heat 24.41 hectares of modern greenhouses. Since the global warming potential of methane is much higher than CO2, energy exploitation of landfills biogas in Crete will result in environmental benefits compared with its direct emission to the atmosphere.