Simulation of wood-pole replacement rate: application to distribution overhead lines

In a previous paper, the authors presented a methodology for simulating the expected wood-pole replacement rate for distribution overhead lines as a function of time, considering the statistical nature of pole strength and climatic loads (wind and ice). Since then, representative costs for wood-pole replacement due to maintenance and mechanical damage have been obtained from Norwegian utilities. This paper demonstrates how the approach can be used as a strategic tool for the mechanical design of new distribution overhead lines, and assessing the economic impact of various maintenance strategies for existing distribution lines. It is shown that for distribution lines designed according to IEC 826, introduction of systematic maintenance replacements for wood poles is not profitable. From 2001, Norwegian authorities will introduce compensation to customers for interruption of electric power. In this case, the proposed compensation will for lines with substantial electrical load make it profitable to introduce systematic maintenance replacements, and to design the lines with increased strength.