Buses are a major item of investment in the urban public transport sector in Australia, yet there has been surprisingly little robust analysis and little consensus on optimum bus replacement policies for urban operations. The paper addresses this issue by reviewing the life cycle costing models used by various Australasian public bus operators, and appraising their structures, their critical assumptions and their findings. It finds a wide range of input assumptions and results. It then reports on the development and application of a bus "life cycle costing" model in the context of Perth's urban route services. It covers the model structure; the development of the key input functions; the results of the model's application in determining optimum bus life; the implications of sub-optimum replacement policies; and the sensitivity of these findings to potential technology and efficiency improvements and other input parameters. It concludes by discussing the implications of these findings for urban bus investment policies throughout Australia. (A)
Abstract