Due to the Hokkaido Eastern Iburi earthquake that occurred on September 6, 2018, the Hokkaido Electric Power Company suffered damage at several of its power plants as well as its transmission and distribution infrastructure, causing a massive blackout in the region. On September 19, 2018, a regional power operator announced that it had restarted the Tomato-Atsuma thermal power plant Unit 1 after a trial operation was successfully performed to gradually increase the output. Prior to the restart of the power plant, the Hokkaido Electric Power Company had set power saving time from 8:30 am to 8:30 pm on weekdays by encouraging energy users to reduce their energy consumption as much as possible, targeting a 10% reduction in electricity demand. After restoring the Tomato-Atsuma power plant Unit 1, the company canceled the power saving time period and resumed its plans for energy saving for the winter season at normal levels. The company is working to bring two more Tomato-Atsuma power plant units back online soon.[1]
Meanwhile, the earthquake caused significant damage to the transmission and distribution facilities that the utility owns and operates. As of September 16, 2018, the Hokkaido Electric Power Company has temporarily restored the No. 71 transmission tower on the Iwachishi line (66kv), and it has been working on repairs on the No. 107 transmission tower, which was destroyed by a landslide. The Hokkaido Electric Power Company expects to restore the No. 107 tower as well as the No. 52 transmission tower on the Karikachi line (275kW) by the middle of November. It also has considered changing to an alternative route for the transmission line, in order to avoid potential long-term landslide risks. There was also significant damage to distribution networks, with a total of 327 supporting facilities, 295 electric wires, and 428 transformers damaged. As of September 16, 2018, the blackout continued to affect 59 homes in Atsuma Town and Abira Town.[2]