Around 1,100 homes and business in Kerry are without power this lunchtime as a result of lightning.
South Kerry is worst affected with almost 750 customers without power on Valentia.
There are also power outages in Cahersiveen, Kenmare, Dingle, Scartaglen and Moyvane.
ESB Networks say all available crews and additional contractors are working since first light working to repair faults.
They hope to have power restored to about 600 customers on Valentia by about half two and expect to have power back to all other customers by tonight at the latest.
ESB Networks are warning people to stay away from fallen lines and to ring their emergency number on 1850 372 999 to report any damaged lines.