President Joe Biden's administration on Oct. 18 announced $3.5 billion funding for projects to protect the aging U.S. power grid from extreme weather and fires and to connect transmission systems with more electricity from renewable energy sources.

The funding for 58 projects across 44 states comes from the bipartisan infrastructure law Biden signed in 2021, Energy Secretary Jennifer Granholm said, and is the largest-ever direct investment in the grid.

"Extreme weather events fueled by climate change will continue to strain the nation's aging transmission systems, but President Biden's Investing in America agenda will ensure America's power grid can provide reliable, affordable power," Granholm said in a release.

The projects will help bring more than 35 gigawatts of new electricity onto the grid from wind and solar and other renewable power and invest in 400 microgrids, or self sufficient energy systems, the Department of Energy (DOE) said. More than 75% of the projects have partnerships with the International Brotherhood of Electrical Workers union and the aim is to maintain or create union jobs, it said.

It was the first round of selections under the broader $10.5 billion grid resilience and innovation partnerships program managed by DOE.

More than $507 million will go the Georgia Environmental Finance Authority and other groups for a project to help remote and under-invested communities by upgrading a smart grid with battery storage, local microgrids and new transmission lines.

In southeastern Pennsylvania, PECO Energy will boost grid reliability and resilience through substation flood mitigation, replacing aging infrastructure, and deploying battery systems for backup power.

Some projects aim to expand transmission across multiple states. In Western states include California, Arizona and Washington, Holy Cross Energy will launch a wildfire mitigation project with a consortium of 39 rural electric co-ops in high threat areas, the DOE said. That will enable hardening of networks with investments in fire resistant infrastructure, putting lines underground, and upgrading overhead lines.