Power has been restored to all but a handful of Central Maine Power Co. customers in Brunswick and Topsham, the utility said.
Shortly after 2 p.m. Saturday, more than 13,000 customers were without power after insulators blew at a Topsham substation, CMP said.
By later in the afternoon, the number had been cut in half. Most were back online about 6:45 p.m., the company said. Only about 300 remained without power in Topsham at that point, and their electricity was restored about an hour later, CMP said.