CA to require PV on new construction homes beginning in 2020

[RegGuheert]

California becomes the first state to require solar on new homes:

Earlier this month, the California Building Standards Commission (CBSC) unanimously approved new standards requiring that, starting in 2020, all new homes in California include rooftop solar.

It's a good idea. I've wanted to see this for a long time.

I'm sure there will be instances where the production will not be very good, but hopefully those cases will be limited in CA.

[SageBrush]

The standard should come with a performance guarantee so that builders learn enough to avoid crap installs and roofs are designed to facilitate PV. In my rural area of Colorado I see new homes built with no consideration of the solar resource. The most idiotic is placing vents on the southern face.

Close to universal PV on new builds will do wonders for the cost of residential PV, driving it down to close to the cost of panels + inverter + hardware. It is a brilliant move. Just being able to draw lines on the board overlaying the rafters before installing the shingles will cut the labor time involved in putting up the rails to not much more than installing the same roof without PV today because most of the time today is finding the rafters. The group I volunteer with is able to put up a 5 - 10 kW roof array in about 10 hours not including the electrician. I doubt it will take more than 10 labor hours given the optimal conditions installation during building affords. And of course the permitting costs are folded into the other work and the electrical work becomes pretty trivial.

The next steps are mandating near PassivHaus envelope standards, heat pumps in appropriate locales, DHW heat scavengers and HRV/ERV. In short, a HERS of 20. Europe has already proven that when widespread these conservation methods do not add to the construction cost of a home and the energy savings are amazing.

[cwerdna]

The standard should come with a performance guarantee so that builders learn enough to avoid crap installs and roofs are designed to facilitate PV. In my rural area of Colorado I see new homes built with no consideration of the solar resource. The most idiotic is placing vents on the southern face.

There seem to be some, from glancing thru the title 24 manual at https://www.energy.ca.gov/2018publicati ... 17-CMF.pdf from https://www.energy.ca.gov/title24/2019standards/.

See page 7-1 (page 385 into the PDF).

[RegGuheert]

In my rural area of Colorado I see new homes built with no consideration of the solar resource.

I find that most people are quite ignorant of virtually everything related to energy and almost no one has thought about solar and how to make it work effectively. Part of this stems from people seeing, to this day, old solar collectors which sit atop a few houses as monuments to what doesn't work.

Most people are not going to be the early adopters. They want to see things working, working well, and for a LONG time before they will commit. After having off-grid PV (which worked O.K., but not great) people did take notice and only a couple were willing to commit to that. Now, after eight years of grid-tied PV with a handful of failures over the years, there is more interest, but people are still skeptical. Our LEAF is now seven years old and people are familiar with its limitations. It will take a bit of time for them to understand what the next generation BEVs are capable of.

But the knowledge of these technologies is gradually spreading through the population. It's a process that takes time, but it is happening.

Many builders in CA will do dumb things with solar for a while, but knowledge of how to do things right will improve with experience.

[DarthPuppy]

This is a huge step forward. There will be times where the panels and inverters are wasted on an inappropriate installation just to tick the box on the checklist. But overall this should be a good net positive.

Expect a lot of minimalist installations. I looked at a town home a few years ago that had solar for each unit. The number of panels would barely cover the base needs of the unit - expect to pay more if you want to use the HVAC. The builder would not deviate to increase the panels to support an EV's needs or install an EVSE. Doing it right would require doing after the project was completed; if you could get approval from the HOA and the permits to make the changes and were willing to pay for it all over again as a retrofit. Just having some solar was all the marketing differentiation they wanted; actually being efficient wasn't a consideration. Now that everyone has to have solar, perhaps the differentiation will come from actually doing it right.

[mwalsh]

I'm glad to hear this. My wife and I have been telling each other for years now that every house should have at least a handful of panels (preferably installed in the most efficient way).

While I expect that many installs will indeed tick the "mandated" box, I think most builders will see an up-sell opportunity, so you'll end up getting larger systems when buyers are either well educated or well persuaded.

Obviously, with the system we have, we're big proponents of PV - no electric bill for over 9 years now; no fuel bills with my car for 9 years and a very minimal fuel bill with her car for 5.5 years (around 6 gallons annually); plus we even get a small check from the utility for overproduction every year, and we don't skimp on what we use at all. What's not to like?

Yes, PV was a quite expensive proposition back in the day, but with the way we've used it a 100% ROI has come very quickly, and the system still produces very close to what it did when first installed. With the more affordable systems available today, along with rising utility rates, I can't imagine anyone NOT wanting to install PV.

PV and EV are probably two of the best decisions I ever made.

[SageBrush]

Many builders in CA will do dumb things with solar for a while,

Not if they have to guarantee performance.

Cwerdna, thanks for the links. I didn't find what you mentioned; which pdf should I look at ?

[SageBrush]

PV and EV are probably two of the best decisions I ever made.

Absolutely. It is a match made in heaven.

[iPlug]

...The next steps are mandating near PassivHaus envelope standards, heat pumps in appropriate locales, DHW heat scavengers and HRV/ERV. In short, a HERS of 20. Europe has already proven that when widespread these conservation methods do not add to the construction cost of a home and the energy savings are amazing.

Agree. California is a great place to take this to the next steps. To this point, home air and water heating has largely been overlooked.

Almost all of our California population resides in relatively moderate climate zones where air-source heat pumps and water heater heat pumps are great fits, and the technology is ready to deploy now. Would like to see mandating their installation in new homes soon.

[cwerdna]

Many builders in CA will do dumb things with solar for a while,

Not if they have to guarantee performance.

Cwerdna, thanks for the links. I didn't find what you mentioned; which pdf should I look at ?

Page 385 of https://www.energy.ca.gov/2018publicati ... 17-CMF.pdf. I've only briefly glanced at that section so I can't say if it's sufficient or not.