Construction workers damaging underground electricity cables contributed to 1,890 power cuts in Northern Ireland last year, according to Northern Ireland Electricity (NIE).
It reports that blackouts affecting 72,000 of customers were also caused by DIY enthusiasts and farmers damaging overhead power lines.
But the company blames contractors working without site drawings for many of the incidents, in which 58 people were injured. The company has recovered £1 million in repair costs.
Says safety and risk manager Roy Coulter: “We hoped the number of damages would substantially decrease because of the downturn in building and construction work. Unfortunately, this is not the case.
“It must be remembered that the saddest statistic of all is that eight people have lost their lives since 2001 because they made contact with the overhead network.
“These deaths are a warning to every contractor, farmer or DIY enthusiast who fails to take note of the proximity of the electrical network to their work area.”