Energy news in brief

** Pacific Gas & Electric began turning off power to more than 50,000 Northern California customers Wednesday evening as dry, windy conditions renewed the threat of fire in a season already marked by deadly, devastating blazes. The utility announced that it had begun cutting power to up to 33,000 customers, with about another 20,000 to follow in a few hours.

** Tribal members inspecting the Line 5 pipeline using a remote underwater vehicle find possible prehistoric stone formations in the Straits of Mackinac that — if confirmed — could affect the route of Enbridge’s proposed pipeline tunnel.

** Enbridge completes the replacement of a 12-mile section of the Line 3 pipeline through North Dakota.

** Dozens of residents join a lawsuit challenging a 66-turbine wind project approved in central Illinois.

** Kentucky announces $8.5 million in funding from its Volkswagen settlement fund to replace about 170 buses with cleaner, more efficient vehicles.

** Kentucky went a year with no coal mining deaths but now has two in less than a week after a miner was killed Tuesday at an underground mine.

** Dominion Energy says its two-turbine offshore wind pilot has completed final testing and is ready to enter into commercial operation soon.

** Large buildings in New York City will begin posting signs of letter grades ranking them for energy efficiency.

** EPA signed a guidance memo last week declaring that states can implement rules that allow power plants and refineries to avoid punishment for exceeding pollution limits during startup, shutdown and malfunctions.

** Activist groups sued EPA on Tuesday over what they contend is a weak new air emissions rule governing hazardous pollutants from roughly 200 chemical manufacturing plants across the country.

** The League of Conservation Voters Victory Fund is spending $1.2 million on a mail campaign against Iowa Sen. Joni Ernst down the home stretch of her competitive reelection bid against Democrat Theresa Greenfield.

** California regulators give automakers until the end of the year to admit to any actions taken or cheat devices installed on vehicles to hide true emissions.