Is it worth generating energy with garbage? Defining a carbon tax to encourage waste-to-energy cycles

• Autor(a) principal: Mollica, Gustavo José Gonçalves [UNESP]
• Data de Publicação: 2020
• Outros Autores: Balestieri, José Antonio Perrella [UNESP]
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://dx.doi.org/10.1016/j.applthermaleng.2020.115195; http://hdl.handle.net/11449/201648
• topic: Carbon tax; Exergetic penalty; Hybrid-cycles; Incineration; Municipal solid waste; Waste-to-energy systems

The rising of municipal solid waste generation is a serious current problem, whose incorrect disposal leads to major impacts to human health and the environment. Waste-to-Energy systems have been some of the adopted solutions but they carry the burden of the emission of pollutant gases. To control such emissions, international agreements have introduced the concept of the carbon tax, i.e. a levy on carbon dioxide emissions imposed on energy systems. Considering the specificity of municipal solid wastes for their inclusion in the energy mix of the countries, this study aims to apply a carbon tax model in Waste-to-Energy plants to encourage the utilization of this particular waste. The proposed carbon tax utilizes the concept of exergy destruction from the second law of thermodynamics and is based on the cycle's efficiency and the type of fuel to be burned. Hybrid-cycles associating gas turbines burning natural gas and an incinerator burning municipal solid wastes were compared to the conventional incineration steam cycle. One finding of this study is that the incineration cycle is less penalized in terms of CO2 emissions compared to the rates applied to hybrid-cycles in the same exergetic base, considering its attribution to the environmental liability destruction represented by the municipal solid waste. The sensitivity revealed that the municipal solid waste price significantly affects the incineration cycle and hybrid-cycles with the lowest gas turbine capacities and natural gas price variations influence large capacity hybrid-cycles.