Fortunately, that's not the only change in their building regulations.
The California Energy Commission has just changed the building standards to require solar photovoltaic systems on all houses built after January 1, 2020. Here I would cue up my usual response and say "reducing demand is more important than increasing supply" but they do that too; Insulation in walls and attics is increased, window performance is improved, LED lighting is mandated and ventilation is improved. Commissioner Andrew McAllister says:
The buildings that Californians buy and live in will operate very efficiently while generating their own clean energy. They will cost less to operate, have healthy indoor air and provide a platform for ‘smart’ technologies that will propel the state even further down the road to a low emissions future.
There are the usual objections that it will increase the cost of housing (estimated to be $9500 per house) but California houses go up by that much every month due to land prices, President Trump's tariff on Canadian lumber caused a 7 percent increase, and you probably heard the same thing when indoor plumbing became mandatory. At least energy savings from building efficiency and solar panels pay for themselves eventually. In the FAQ they write: "Based on a 30-year mortgage, the Energy Commission estimates that the standards will add about $40 per month for the average home, but save consumers $80 per month on heating, cooling and lighting bills.
I do wonder what they are actually going to do with all this solar power given that they already are close to over-generation when the sun shines, and suspect that there is going to be one very fat duck after a few years of this. However the commission is also promoting batteries, and new housing only adds one percent per year to the housing stock in California, so it's not feeding the duck too much too fast. And who knows, maybe Elon will have delivered some Model 3s by then that can be plugged into the "smart" technologies and suck some of it up. The Commission acknowledges that there are issues here:
It is ideal to generate the electricity and have it used onsite versus exporting it to the grid at a time it may not be needed. When the rooftop solar generation is entirely used to offset on-site electricity consumption, then the home has virtually no impact on the grid, reducing the home’s climate change emissions. Looking beyond the 2019 standards, the most important energy characteristic for a building will be that it produces and consumes energy at times that are appropriate and responds to the needs of the grid, which reduces the building’s emissions.
Here's an idea, California: instead of requiring all new homes to have solar panels on them, require all new homes to have, like, five more homes on them. A vertical stack of homes is better for the climate than a single home with panels. https://t.co/2DDudo6wnF— David Roberts (@drvox) May 8, 2018
Almost everybody is so excited about the solar, but I am more excited about the efficiency improvements. A lot of people are still burning gas for heat, and solar panels don't change that. Rachel Golden of the Sierra Club notes in Greentechmedia:
While we’re very pleased and supportive of the building code…it really is zero net electricity, not net zero energy, because it doesn’t take into account gas use in homes and buildings, and gas use makes up about 40 percent of a home’s greenhouse gas emissions.
Going net zero electricity is very different than going net zero carbon, which is much easier to do if you make houses radically more efficient. Apparently, that is where the California Energy Commission is going with its downplaying of Net Zero. All a step in the right direction.