This paper presents a novel approach to quantify the effect of customer-owned distributed generation (DG) units on the life expectancy of power cables. Numerical results obtained from a realistic distribution system are presented and discussed under various scenarios, including different penetration levels of DG technologies. The results show that despite differences among various DG technologies, significant benefits can be realized in the area of power cable life extension, when DG units are installed by low-voltage customers. However, the extent of the benefits largely depends on the penetration level of DG units, the production pattern of DG technologies and the utilization factor of the analyzed cables. Copyright © 2013 John Wiley & Sons, Ltd.