For over three decades cable rejuvenation using dialkoxysilane fluids has been the most capital efficient method to prevent cable failure due to aging resulting from all manner of defects including but not limited to water treeing, electrical treeing, and manufacturing defects. Over the last decade rejuvenation has surpassed replacement as the most utilized method of rehabilitation.

The work presented in this paper utilizes very large data sets to compare the post-installation reliability of rejuvenation and replacement. The results shed light upon off-line partial discharge diagnostic testing. Either or both of the following propositions are true: (1) Electrical trees are rare and/or (2) rejuvenation adequately addresses electrical trees. Data to support both propositions are presented.