Energy efficiency in the integrated water service: the case study of the replacement of the air diffusion system in the biological treatment section of the SMAT plant in Castiglione Torinese, in the context of the White Certificates mechanism

The current geopolitical setup of the European Union, especially following the abrupt escalation of the Russian-Ukrainian crisis that has been ongoing since 2014, has highlighted the need for EU policy to attribute crucial importance to the energy sector. The European Union's energy vulnerability, as well as the need to deal with climate-altering gas emissions, has prompted EU policy to take measures to reduce energy consumption, using energy efficiency as the first tool to deal with the energy and climate crisis. In this context, in Italy, the white certificate mechanism plays a crucial role in promoting interventions to achieve the nation's energy-saving goals. This thesis work first analyzed the socio-economic structure of the European Union and the related risks and policies in the context described above. In particular, an in-depth dissertation on the white certificate mechanism adopted in Italy, in order to incentivize energy efficiency interventions, is provided. Among the interventions eligible by the mechanism, the case study of the replacement of the air distribution system in the biological treatment tanks, at the SMAT WWTP in Castiglione Torinese, is analyzed. The energy efficiency obligations acquired as a result of the intervention were estimated, using algorithm number 4 found in the operational guide prepared by GSE for interventions that can accrue white certificates. In this context, the necessary parameters were estimated, consistent with the public data available for the plant under consideration. The drafting documentation required to obtain the certificates has been provided. In order to contextualize the plant's economics, the investment's payback period was calculated, considering the actual data of the outcome of the call for tenders for the replacement of the diffusers and the incoming cash flow resulting both from the energy savings and the incentive. Finally, given the centrality of the fight against climate change, the reduction of greenhouse gas emissions generated by the efficiency intervention was calculated, according to GHG Protocol.