摘要:In the article 'Energy and air emission implications of a decentralized wastewater system' published in Environmental Research Letters (2012 Environ. Res. Lett.7 024007), Shehabi et al compared a decentralized and a centralized system on the basis of energy use, greenhouse gas emissions and air pollutants, and claimed that economies of scale lower the environmental impacts from a centralized system on a per-volume basis. In this comment, we present literature and data from New York State, USA to argue that the authors' comparison between a small decentralized system (0.015 MGD) and a large centralized system (66.5 MGD) is unconventional and inappropriate.