Pacific Gas and Electric Company (PG&E) has filed a proposed 10-Year Electrical Undergrounding Plan (EUP) with the California Office of Energy Infrastructure Safety (Energy Safety). The plan outlines a risk-based approach to placing electric distribution lines underground in high wildfire-risk areas across Northern and Central California.

Under the proposal, approximately 5,000 miles of electric distribution lines would be placed underground from 2028 through 2037 in areas where undergrounding is forecast to provide the greatest reduction in wildfire risk. PG&E said undergrounding in these areas can reduce ignition risk by nearly 98% and result in approximately 90% fewer outages.

The proposed work would take place in more than 30 Northern and Central California counties. PG&E estimates that completing 5,000 miles of undergrounding could also avoid approximately $6 billion in vegetation management, operations and maintenance costs over the life of the assets.

"Placing powerlines underground provides the most effective way to reduce wildfire risk and enhance reliability for customers within High Fire-Threat Districts," said Peter Kenny, PG&E Chief Delivery Officer and Electric Transmission and Distribution Senior Vice President. "A 10-year plan allows us to develop and execute projects with increased efficiency, which translates into cost savings for customers, all while delivering enhanced safety and reliability to the hometowns we are privileged to serve."

Proposed Benefits

According to PG&E, the 10-year plan is intended to provide several long-term benefits:

• Reduced wildfire risk: Undergrounding is expected to reduce wildfire risk by 98% on lines moved underground.
• Fewer outages: Customers served by underground lines experience approximately 90% fewer outages.
• Reliability for critical facilities: Undergrounding can improve reliability for hospitals, fire stations, police stations and other essential community services.
• Lower long-term costs: PG&E estimates that 5,000 miles of undergrounding could avoid approximately $6 billion in vegetation management, operations and maintenance costs over the life of the assets.
• Technology and process improvements: PG&E said new technologies and processes have reduced undergrounding costs per mile by approximately 25%.
• Long-term planning: A 10-year roadmap is intended to provide greater certainty and coordination among customers, local agencies, suppliers, vendors and other stakeholders.

Investment and Cost Considerations

PG&E estimates that the plan would provide long-term benefits valued at $117 billion through wildfire prevention and reduced outages. The company said this value is more than 10 times the proposed investment and would include approximately $6 billion in avoided vegetation management, operations and maintenance costs over the lifespan of the underground assets.

PG&E said its undergrounding cost per mile has decreased by approximately 25% over the last few years. The company expects a 10-year plan to support additional improvements in planning, construction practices and supply chain coordination that could improve efficiency and reduce costs over time.

Energy Safety will review the proposal to determine whether it substantially increases reliability and substantially reduces wildfire risk. If approved, PG&E will submit the plan and an application to the California Public Utilities Commission (CPUC) requesting conditional approval of the plan's costs.

Risk-Based Approach to Undergrounding

PG&E said the plan uses data analytics and risk modeling to identify locations where undergrounding is expected to provide the greatest benefits for customers and communities.

The company's analysis considers wildfire likelihood and potential consequences, system reliability, customer impacts, project costs and benefits, and how undergrounding compares with other wildfire mitigation measures.

Where undergrounding is not considered the most appropriate option, PG&E may use other system upgrades, including strengthened poles, covered powerlines and other overhead improvements. The company said the approach is intended to direct investments toward solutions that provide the greatest overall value while maintaining a focus on safety and reliability.