So the actual cost of the system might wind up at less than a quarter of what PG&E claims.

And none of that money — none — would come from taxpayers. The PUC could issue only revenue bonds, backed by future electricity sales, to finance any buyout or construction. No tax money would ever be in play. And our past analyses have consistently shown that the city could buy out PG&E's system, cut electric rates, and still wind up with a sizable surplus every year.

Newsom is aware of all of this, and has said that he's willing to consider supporting public power. Now there's a measure heading for the ballot that would also mesh with all of the mayor's environmental goals. The only argument against it is that PG&E — in the past a backer of the mayor — doesn't want it to pass.

Newsom needs to support the Clean Energy Act. If he doesn't, it will demonstrate that he lacks the backbone to stand up to special interests — and has no business running for governor of this state.

A kickoff press conference on the Clean Energy Act will be held at 11 a.m. Tuesday, July 22 on the steps of City Hall.