The Impact of Utility Lines in Fires

Thursday - August 31 2023, 13:41 UTC - 1 year ago

Utility lines are often suspected in fires due to the variety of ways electricity can spark blazes. Utilities are obligated to provide safe, reliable power, and have a responsibility for fire safety. They can manage fire risk by warming citizens, trimming trees, moving lines underground, replacing old equipment, and using AI-driven techniques to forecast fires.

Why are utilities so often suspected in fires? .

There are a lot of ways that utility lines, particularly high-voltage lines, can spark fires. If tree branches are too close to the lines, electricity can arc between the line and the tree. Old equipment can set off sparks. If the weather gets really hot, power lines can sag and touch dry grass or trees. If there’s a lot of wind, that can push a power line into tree branches or damage equipment. All of those can and have been fire-starters. In California, a state audit found that electrical power caused 10% of all wildfires and was responsible for nearly 20% of all acres burned from 2016 to 2020. Those were also some of the most destructive fires in state history – including the 2018 fire that destroyed the town of Paradise. Pacific Gas & Electric pleaded guilty to 84 counts of involuntary manslaughter in that case and one felony count of unlawfully starting a fire.

Do utilities have a responsibility for fire safety? That’s the question at the heart of litigation and debates. Public utilities’ obligations can vary state to state. In general, regulated utilities have a duty to provide safe, affordable, reliable power to their customers. That can mean making tough choices. Let’s say it’s really windy, dry and hot – ideal conditions for spreading a wildfire. The utility can shut off power, but that means people don’t have air conditioning in what may be extreme heat. People with health issues – who might need oxygen, for example – might not be able to run essential medical devices. Electricity is critical infrastructure and a foundational bedrock to many other services. Cellphone service can be lost if transmission towers lack backup power, so when power goes out in a disaster, people could lose access to crucial information. Water pumps used in wells and water treatment also need electricity. Many municipal water systems have backup generators to keep water flowing, but small water systems might not. Texas learned about cascading dependencies during the deep freeze in February 2021. When power systems failed, the pumps used to send gas and oil through pipelines went out. That meant power plants weren’t getting the gas they needed to operate.

Utilities have to balance the risk of keeping power on with the risks created by shutting power off.

What can utilities do to manage fire risk? Utilities can make sure they’re careful about trimming trees, cutting grasses and removing other dry fuel that can ignite near power lines. In really high-risk areas, they can move their lines underground. There’s an effort to do that in California, but estimates show it would be prohibitively expensive to take all high-voltage lines underground. To give you a sense of the amount of line we’re talking about, in 2021, California utilities reported having nearly 40,000 miles of bare power lines in areas at high risk of wildfires. Utilities are constantly actively looking for fire risks, whether it’s replacing old transformers or upgrading lines that might be overloaded or clearing away foliage. Technology also helps identify risks. Sensors can detect sparks on a power line. Neuromorphic fire detection techniques use artificial intelligence or machine-learning models to foretell conditions that could lead to wildfire.