For the tenth year in a row, Canadians took part in Earth Hour and dimmed their lights to help save electricity. In Simcoe County, Power Stream reported a reduction in use of 43 megawatts. Which translates into enough electricity to power over 13-hundred average size homes for a 24 hour period. Earth Hour has grown in recent years to include 7-thousand cities in 172 countries taking part in the event. Even Prime Minister Trudeau took part. Turning the lights off at Rideau Hall Cottage.