Carbon emissions analysis of rail resurfacing work: a case study, practical guideline, and systems thinking approach

Carbon pollution has become a sensitive topic across the globe. In Australia, an incentive has been provided to industry in order to reduce carbon emissions in heavily polluting industries. The railway transportation system is one of the industries expected to reduce the emissions and contribute to a long term reduction strategy, although comparatively the rail sector contributes much less carbon compared with other modes of transportation. Railway operations provide fast and safe transport of passengers and cargo whilst providing alternative transport modes to road and aviation. Railway maintenance is the process of restoring railway tracks to an appropriate condition which improves ride comfort and safety through its life cycle. Railway maintenance practices need to be cost effective, with the longevity of railway infrastructure a key long term consideration. Railway maintenance activities include tamping, rail grinding and track renewals. In order to understand the contribution railway maintenance machinery has on overall greenhouse gas emissions, this paper presents a method for estimating emissions from rail resurfacing practices. A study was conducted to survey diesel engines used in various resurfacing machinery. Emissions are estimated using a fuel consumption and operating time analysis. The contribution machinery has on greenhouse gas emissions and other air pollutants include carbon dioxide, carbon monoxide, nitrogen oxide, sulphur dioxide, PM ten, TVOC and polycyclic aromatic hydrocarbons. The results were compared to the National Greenhouse and Accounts Factors and the Australian National Pollution inventory databases, to verify the accuracy of the estimations.