Research: Rolling Stock Replacement vs. Refurbishment

This research project examined metros’ practices when making the decision of whether to replace or refurbish ageing rolling stock.  As annualised expenditure on rolling stock is typically about 20-25% of total operating costs, fleet investment decisions have significant impacts on overall metro costs.  The focus of the study was to identify key factors and criteria in deciding to replace or refurbish rolling stock at end of nominal life, including the risks and opportunities of life extension beyond initial design life; to identify best practices in design, specification and planning of refurbishments; and to advise metros on appraisal and business case development process, parameters and assumptions.

Metros have been gaining increasingly significant benefits through refurbishment, and many metros (especially newer ones) are now undertaking or planning refurbishments to ageing fleets that are approaching or past their initial design lives.  These refurbishment programmes are designed to extend initial design lives by as much as 15-20 years.

Cost saving opportunities of refurbishment
Cost saving opportunities of refurbishment

A key guiding principle is that refurbishment prolongs ‘more of the same’, as reliability following refurbishment tends to remain fairly similar. Therefore, only highly reliable fleets are usually worth refurbishing. A second principle is that most metros limit the extent of technology change attempted through refurbishment. So if significant upgrade is required, for example to enable unattended train operations, generally a new vehicle is preferred.

This case study has successfully assisted CoMET and Nova members in their decision-making. An Asian member needed to buy new trains when their 15-year-old line was extended and re-signalled. Findings from this report assisted with their decision to replace all the trains on the lines, instead of converting the older trains to work with newer signalling and then operating a mixed fleet. Conversely, Montréal STM used this research in support of a decision to refurbish their 40-year-old MR-73 cars and extend their life to 60 years. This is projected to save Quebec taxpayers nearly $500 million over the next 20 years. More information on Montréal’s decision can be found here.