Petaluma’s city leaders Monday night dug into the structure and risks of the planned Sonoma Clean Power Authority, an alternative to utility giant PG&E promised to bring a greener product to county residents.

With four cities down and four to go, Sonoma County officials this week enter the second half of their roadshow to convince cities to take part in the county’s planned public power agency.

The presentations are intended to tout benefits and answer questions about the effort to displace Pacific Gas and Electric Co. with an alternative that offers a higher share of energy from renewable sources.

Windsor on Wednesday became the first city to join the Sonoma Clean Power Authority, created as an alternative to PG&E to provide a greener product at competitive, if not cheaper rates.

Third District Supervisor Shirlee Zane aimed high at the Rohnert Park City Council on Tuesday, as the political campaign to convince cities to join the county’s public power agency continued.

Plans for a public power agency and the renewable energy projects that could sprout with it appear to have scrambled politics in Sonoma County.

The Cloverdale City Council has said it’s premature to join a public power agency intended to supplant PG&E as the city’s primary source of electricity.

Sonoma County officials made their first pitch for a public power agency on Tuesday night to the Sebastopol City Council, with seven more stops to go in a campaign to enroll eight cities in a plan to supplant PG&E as their sole source of electricity.

Four energy companies have emerged from a group of 11 competing to become the main electricity supplier to Sonoma County’s planned public power agency.

Sonoma County officials have announced a schedule of presentations to local city councils over the next two months on the county’s plans for a public power agency.

The Sonoma County Board of Supervisors Tuesday voted to implement a public power program for all homes and businesses outside city limits with plans to expand countywide.