Consumers and organizations worldwide are searching for low-carbon alternatives to conventional gasoline and diesel vehicles to reduce greenhouse gas (GHG) emissions and their impact on the environment. A comprehensive technique used to estimate overall cost and environmental impact of vehicles is known as life cycle assessment (LCA). In this article, a comparative LCA of diesel and compressed natural gas (CNG) powered heavy duty refuse collection vehicles (RCVs) is conducted. The analysis utilizes real-time operational data obtained from the City of Surrey in British Columbia, Canada. The impact of the two alternative vehicles is assessed from various points in their life. No net gain in energy use is found when a diesel powered RCV is replaced by a CNG powered RCV. However, significant reductions (approximately 24% CO2-equivalent) in GHG and criteria air contaminant (CAC) emissions are obtained. Moreover, fuel cost estimations based on 2011 price levels and a 5-year lifetime for both RCVs reveal that considerable cost savings may be achieved by switching to CNG vehicles. Thus, CNG RCVs are not only favorable in terms of reduced climate change impact but also cost effective compared to conventional diesel RCVs, and provide a viable and realistic near-term strategy for cities and municipalities to reduce GHG emissions. (C) 2012 Elsevier Ltd. All rights reserved.