PG&E wildfires
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US utility Pacific Gas and Electric Company (PG&E) has started de-energising its grid in areas with severe weather conditions as part of efforts to avoid igniting wildfires.

PG&E has started cutting off power for 172,000 customers in portions of 22 counties as part of a Public Safety Power Shutoff (PSPS).

The PSPS event will affect customers in northern Sierra Foothills, northern Sacramento Valley, and elevated North Bay terrain.

The event is based on forecasts of widespread, severely dry conditions and strong, gusty winds that create critical fire weather with high ignition risk.

The dry conditions are expected to continue through Wednesday morning.

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Windy conditions, like those being forecast, increase the potential for damage and hazards to the electric infrastructure, which could cause sparks if lines are energised. These conditions also increase the potential for rapid fire spread.

Once the high winds subside, PG&E will inspect the de-energised lines to ensure they were not damaged during the wind event, and then restore power within 12 daylight hours for all affected customers.

PG&E will use temporary generation and islanding to enable about 69,000 customers and several medical facilities to stay energized.

“We are working to improve our PSPS programme by making events smaller in size, shorter in length and smarter for our customers. Although the National Weather Service has placed 1.5 million customers across our service territory under Red Flag Warning conditions, we have been able to limit public safety PSPS de-energisation to less than 12% of those customers now under Red Flag Warning risk.

“While PSPS is an important wildfire safety tool, we understand the burden PSPS places on our customers especially for those with medical needs and customers sheltering-at-home in response to the novel coronavirus (COVID-19). We are working to reduce the number of customers affected and the length of time they are without power,” according to a statement.

To ensure its PSPS programme prevents the ignition of wildfires while continuing customer services, PG&E will:

  1. Ensure smaller, shorter, smarter PSPS events

PG&E is learning from past PSPS events, and this year will be making events smaller in size, shorter in length and smarter for customers.

  • Smaller in Size: This year, PG&E expects to cut restoration times in half compared to 2019, restoring power to nearly all customers within 12 daylight hours after severe weather has passed, by:
    • Installing approximately 600 devices that limit the size of outages so fewer communities are without power
    • Installing microgrids that use generators to keep the electricity on
    • Placing lines underground in targeted locations
    • Using better weather monitoring technology and installing new weather stations.
  • Shorter in Length: To make events shorter, PG&E expects to restore customers twice as fast by:
    • Expanding its helicopter fleet and using new airplanes with infrared equipment to inspect at night
    • Deploying more PG&E and contractor crews to inspect equipment and restore service.
  • Smarter for Customers: In order to make events smarter for customers, PG&E is:
    • Providing more information and resources by improving the website bandwidth and customer notifications, opening Community Resource Centers, and working with local agencies and critical service providers
    • Providing more assistance before, during, and after a PSPS event by working with community-based organisations to support customers with medical needs making it easier for eligible customers to join and stay in the Medical Baseline programme.

2. PG&E will open Community Resource Centers in every county where a PSPS occurs to reduce the risk of major wildfires during severe weather.