State Sen. Scott Wiener’s legislative effort to place new restrictions on utility fire-prevention blackouts cleared the Senate floor on Monday.

Senators voted overwhelmingly in favor of advancing the bill carried by Wiener, D-San Francisco, which would create a way to make Pacific Gas and Electric Co. and other large investor-owned electric companies in California pay customers for losses they incur during power shut-offs. The bill, SB378, now heads to the Assembly for consideration.

Wiener proposed the legislation last year as PG&E warned it could turn off power to swaths of California when dry and windy weather conditions made the company’s power lines more likely to start devastating wildfires like the disasters of 2017 and 2018. PG&E subsequently left millions of people without electricity over the course of multiple preemptive blackouts in October.

SB378 would require state regulators to set up a process for homes, businesses and local governments to seek compensation from PG&E and other electric companies after blackouts. If state regulators determined that a company did not turn off power in “a reasonable and prudent manner,” the bill would subject utilities to a $250,000 hourly penalty per 50,000 homes or businesses affected by the blackout.

“This is about ensuring that these blackouts are not broader and longer than they need to be as a matter of public safety,” Wiener told his Senate colleagues.

Supporters of the bill included the San Francisco Public Utilities Commission, the cities of San Jose and Oakland, the Berkeley City Council, and Alameda County.

PG&E, Southern California Edison, San Diego Gas & Electric and a utility workers’ group were among the bill’s opponents. In a formal opposition message to lawmakers, PG&E said SB378 would “put customers in a very dangerous position” by punishing utilities for turning off power “when weather conditions and fire risks warrant such action.”

The company said Wiener’s bill might force it to turn power back on before it could finish “necessary patrols and inspections that are designed to protect public health and safety.”

“SB378 would taint the utilities’ (power shut-off) decision-making processes, and could ultimately lead to future tragedies,” PG&E said in its opposition message.

Republican state Sen. Brian Dahle, R-Bieber (Lassen County), said he would “lay off” Wiener’s bill for the time being but voiced concern about its focus. He said the Legislature should be looking at regulators at the California Public Utilities Commission instead. (The commission is already conducting its own formal investigation into last year's power shut-offs.)

Wiener responded that he had had his “fair share” of criticism for the commission, but pinned the responsibility to prevent fires and keep electricity flowing squarely on utilities such as PG&E.

“It is PG&E in particular that has allowed its system to fall apart, that has put everyone in this terrible position where we now have to have these kinds of conversations,” Wiener said.

J.D. Morris is a San Francisco Chronicle staff writer. Email: jd.morris@sfchronicle.com Twitter: @thejdmorris