[TexasEcon23]

>> No, solar on single family homes makes them less expensive.

Then why in the world would they have to regulate it?

>> the body that enacted that would not have been allowed to enact the regulation

That 100% wrong legally. No one ever has been able to avoid regulation by claiming that the regulation imposes a net cost. That's the entire point of a regulation, to shift behavior in the absence of direct economic incentives.

In reality, this regulation is a tradeoff between higher net costs for new home builders and the need to reduce carbon emissions.

[epistasis]

You don't understand, the body that enacts these regulations enacts them on the basis of cost savings. It's the California Electricity Commission:

http://www.energy.ca.gov/efficiency/savings.html

There is no net new cost, overall, this is all win, and if it were not, the standards would not be allowed to be set. In particular, on average, the CEC found $80 of savings on $40 of finance cost:

http://www.energy.ca.gov/releases/2018_releases/2018-05-09_b...

Now, you seem to be implicitly assuming that if this cost savings were true, it would already be done by builders and consumers. However, human behavior is sticky. Even though this is a good idea now, it takes people a long time to realize that.

Witness all the people in this thread that seem to doubt it's not a cost saving measure. Even taking a small peak at the cost of solar should reveal how much of a cost saving measure solar is in California. Even residential, which has high labor costs, and where 30% of the cost of an install goes to customer acquisition costs. For new large builds, that customer acquisition cost goes away, so it becomes an even better deal. And you've already got people on roofs, building them, so it becomes yet an even better idea.