ScottishPower started the connection work in June 2008 and used its own in-house team to erect the 95 pylons in order to provide power to the nine-property village.
Gary Evans, new connections manager at ScottishPower, said the firm worked with the local and county council in order to deliver the project, adding the design and construction did throw up "many challenges" over the period.
He added: "Although we had a lot of issues to consider and hurdles to overcome, our project team showed great dedication and commitment to finish the project in time and we are very pleased that the residents of Abergeirw are now fully connected to the National Grid."
ScottishPower recently announced it was launching a new social tariff to help its most vulnerable customers save an average of £211 a year on their energy bills.
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