I really think mandates like this are totally wrong approach. Consider that in virtually every jurisdiction in California a new home requires both solar power and a 2-car garage. If that isn’t perverse I don’t know what would be.
Unlike you I consider a carbon tax almost trivially easy to implement. Way easier and more effective than construction mandates.
Utilities can kick and scream (and attempt to subvert the mandate to maintain their relevance), but the mandate will go into force.
> Commission officials acknowledged homeowners will see smaller bill savings under SMUD’s Neighborhood SolarShares program than they would with solar panels on their roofs.
> The average single-family home in the utility’s service territory, which covers most of Sacramento County and parts of Placer and Yolo counties, can currently save around $75 a year with rooftop solar, the Energy Commission estimated. Under SMUD’s program, the average single-family home will be guaranteed electricity bill reductions of just $28 a year.
> The changes from SMUD’s initial proposal didn’t convince critics from several prominent environmental groups, including the Sierra Club and the Center for Biological Diversity. They argued the solar projects SMUD plans to use for its program are too large and generally too far from residential neighborhoods to be considered true “community” solar facilities.
https://www.latimes.com/environment/story/2020-02-20/califor...
[1] https://www.smud.org/en/Corporate/Environmental-Leadership/P...
Utility scale makes sense, but so does rooftop solar at scale (if you can streamline soft costs; permitting is unnecessarily expensive AF in the US versus someplace like Australia). A pollution tax will take time to implement, if at all tenable in American politics. Unfortunately, indirect methods are needed at times due to the political landscape. I will take a decent solution today over the perfect solution when it's too late.