Technico-economic modelling of maintenance cost for hydroelectric turbine runners

Large utilities need to optimize investments to maintain their assets. For a utility like Hydro-Québec (37 GW of installed power) an important part of those investments is used to maintain their hydroelectric facilities. To minimize the maintenance costs, technico-economic model are essentials. They allow to propagate the uncertainties associated with the degradation processes for a given component. Therefore, we developed two technico-economic models for Francis hydroelectric turbine runners: one for crack propagation and one for cavitation. Since these are the main degradation mechanisms leading to failure of Francis runners, they enable us to study the effect of maintenance strategies on the maintenance cost. The models have been created using VME, an asset management software developed by EDF R&D (Électricité de France). VME uses Monte-Carlo simulations to generate stochastic failure dates and obtains probabilistic indicators of the net present value of a given management strategy. Using data based on a HydroQuébec (Québec, Canada) facility, we illustrate the importance of the proper assessment of current and expected long-term reliability on maintenance cost. 1 T. Lamothe() Ecole de Technologie Supérieure, Montreal, Canada email: thibaud.lamothe.1@etsmtl.net 2 M.Blain IREQ, Varennes, Canada email: blain.michel@ireq.ca 3 M.Gagnon IREQ, Varennes, Canada email: gagnon.martin@ireq.ca 4 J.Lonchampt EDF R&D, Chatou, France email: jerome.lonchampt@edf.fr 5 A.Tahan Ecole de Technologie Supérieure, Montreal, Canada email: antoine.tahan@etsmtl.ca 2 T.Lamothe et al.