Urban metabolism of Aveiro: LCA of the city demands and water cycle

Abstract

This study analyzed the urban metabolism of the city of Aveiro with a consumption-based perspective. The MFA coupled city scale data of energy, water, wastewater and solid waste with downscaled national data, getting a total mass of inputs equal to 163 kg/cap/day and of outputs equal to 148 kg/cap/day, the difference being due to net accumulation. An economic IO analysis was done for the household expenses and found a total impact of 26 kg CO2-eq./cap/day for climate change (CC) and 7 kg oil eq./cap/day for fossil depletion (FD). The process LCA was done using the products and processes quantities estimated with the MFA. The process LCA total impacts were 27 kg CO2-eq./cap/day for CC, 8 kg oil eq./cap/day for FD and 3 points/cap/day for the ReCiPe endpoint impact. It allowed also the discrimination of products that contributed to more than 1% of each impact (priority products). Process LCA was also applied to the water cycle of Aveiro to compare local impact factors with the ones used from LCA databases. It was observed that the local impact factors of the water cycle were more than 2 times higher, showing the importance of carrying detailed local studies, especially for priority products.