To the Editor:
I for one am in favor of the new poles. Driving around the Island and looking at the condition of the existing poles that are carrying the power supply to our homes, they are obviously old and splintering, leaning, and some appear to be straining from carrying the weight that is on them now. New cables on new poles equates to better reliability for us who live here. Just a few winters back we had several ice storms that snapped the existing poles like twigs. I do not like being without power during those colder months. I commend NSTAR for taking the steps to increase our reliability in a product that we expect to be there when we turn on the switch, at any time day or night, winter or summer.
With regards to going underground. Placing cables underground has several drawbacks. The cable needs to be heavily insulated, and therefore the cable has difficulty in dissipating the heat that is generated when high usage loads are required. If you design for higher loads, that means larger and more costly cables. Larger cables are also more difficult to work with when repairs are required, especially in the winter when things just don’t bend as easily. Most underground cables fail as a result of corrosion when the salt that is spread on our roads melts, and the salt and ice mixture drains into the electric manholes. Overhead lines can handle much higher loads, because they can dissipate the heat much better in open air, and therefore can be pushed to higher limits without failure.
When cables are installed in manholes, the manhole would contain multiple circuits, for reliability. If a cable fails in the underground system, what would be the safety policy of NSTAR when sending their workers down into a manhole where a cable failed, to de-energize all of the cables in the manhole so that safety can be maintained? That would mean that all of those customers being fed by all of the cables running through that manhole would be without power for the duration of the repair.
Risking a worker to work in a manhole with energized cables that just experienced a cable failure is a very risky procedure. Most underground cable failures are violent and could cause damage to adjacent cables. Moving these cables during work procedures could subject the workers to injury or death. Not a risk that I would support.
Klaus F. Broscheit