Can you provide third party data demonstrating that cable injection will extend the life cycle of underground cables? My colleagues and I are preparing for a rate filing with the OEB and we are looking for some firepower, facts and figures to bolster our case for additional cable injection monies for 2014 and beyond.
I can think of four “flavors” of third-party data.
Flavor 1 includes data gathered by third parties at the behest of a firm engaged in rejuvenation. The third party is independent, and is generally working for the technology supplier. There is an ample supply of this type of data, spanning over two-and-a-half decades. As an example of this type of data, consider Figure 3 of the paper published by my colleagues at the IEEE International Symposium on Electrical Insulation in September 2004…
Figure 3 shows the substantial improvement in AC break-down performance seven days after injection at Cable Technology Laboratories. There are an abundance of similar Flavor-1-third-party data. A compilation of these data can be found in the bibliography presented at the NETA Powertest Electrical Conference on March 17, 2008.
This paper provides 50 references including flavors 1, 2, and 3 of third-party data.
The second flavor of third-party data are results reported by end-users. There have been several North American utilities that have reported their post-rejuvenation reliability over multiyear periods. The IEEE’s Insulated Conductor’s Committee (ICC) Discussion Group C30 is compiling several of these case studies as part of its efforts to craft a Guide entitled, “Extending the Life of Power Cables in the Field.”
The third flavor of third-party data is the overall failure rate of rejuvenated cables. Circuit owners have an incentive to report their post-injection reliability issues as they get cash for doing so! Novinium’s post rejuvenation failure rate is less than that of new cable! Check out my March 23, 2012 post, “Better Than New” to learn more.
Flavor 4The fourth flavor of third-party data would be a side-by-side “taste test” of different rejuvenation technologies funded by electrical circuit owners and conducted by a third-party laboratory. There is good news, there is bad news, and some new that falls between good and bad. The good news is such a test was arranged by NEETRAC (National Electric Energy Testing, Research & Applications Center) sponsoring firms including: AEP, BG&E, ConEd, Oncor, FPL, Exelon, Southern Company, PEPCO, Southwire, and Snohomish Public Utility District. The bad news is that the other technology supplier participated in the experimental design, but withdrew just as the testing was to commence citing, “Business and commercial reasons.” The test proceeded with Novinium only. The news is not bad, but not ideal is that even though the test was completed about two years ago, NEETRAC has not yet published the results in anything other than draft form. An excerpt of the draft NEETRAC report provides the bottom line of the testing:
“ … the stress at which the rejuvenated cables fail is higher than for the non rejuvenated cables: 26 kV/mm and 16 kV/mm, respectively. These stresses are taken at the 50th percentile (median). Moreover, it would appear that the [Novinium] rejuvenated cables have a threshold for failure at 4.5 kV/mm whereas there is no threshold for the Non Rejuvenated cables.”
The reported performance advantage was measured after about 18 months of accelerated aging – well beyond the originally planned twelve-month experimental plan. The electrical stress of a typical 175 mil insulated URD cable energized at about 8kV to ground is 1.8kV/mm. The treated failure threshold is 2.5-times typical operating voltages even after extended thermal and electrical accelerated aging.