Pat Rabbitte (Dublin South West, Labour) | Oireachtas source

Deputy Moynihan is correct. It is technically feasible, but the cost that comes with it is the issue. For example, one could run an AC cable and, upon reaching a particularly scenic area, nothing would prevent one from putting the cable underground, but it could not be for a long distance. Doing that would require a DC cable. Take something as simple as the Tyrone-Meath line. The international expert commission concluded that putting it underground would have approximately 3.1 times the cost of traditional AC overhead transmission. Deputy Colreavy referred to some of the other reports that have been done. They suggest that the cost would be even more. It is around that figure.

This is a major factor, but it is not the only one. After a year of study in Denmark, for example, and despite having no difficulty with affording such an approach and so on, it decided not to go underground with 440 kV cables for a combination of reasons, not just cost, but also technical considerations in term of how easy it was to find a fault, etc.

It is complex terrain.

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