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California Votes to Require Rooftop Solar Power on New Homes

bloomberg.com

31–40 of 329 posts

Re: California Votes to Require Rooftop Solar Power on New Homes

#31

Not only is residential solar just about the most expensive (and thus innefficient) form of solar power available, but this is coming at a time when new construction of affordable housing is most needed. The only reason this is considered a 'cost effective' measure, is because the entire cost is forced on the shoulders of homebuyers. Saddling all new residential construction with this burden serves 2 priary purposes…

The article says it will add $10k to the home. On a 30 year fixed rate mortgage at current rates that's $50/month. Subtract out the savings on the electric bill, and it probably won't be reducing affordability much, or even at all.

Re: California Votes to Require Rooftop Solar Power on New Homes

#33

So I guess putting up shade trees to reduce cooling costs isn't a thing any more? Is it net positive to use solar panels? Trees and houses just won't go together any more?

Solar panels are vastly more effective than a shade tree for keeping a home cool.

The geometry of trees and solar panels changes with latitude, but in California you can still have tall trees fairly close to your house while using solar panels. Further, roof panels can also shade your roof though with proper insulation that should not be significant.

Re: California Votes to Require Rooftop Solar Power on New Homes

#34
I'm a homeowner in southern California. I've looked into it and a solar system would cost me about $15k and it would pay itself off after about 8 years.

However that assumes constant price conditions. If there's a glut of solar installations, prices for daytime generation may fall to where it no longer offsets all evening/night consumption. Once that happens you're forced to either invest in extremely expensive battery storage, or the breakeven date gets radically extended out into the future.

Overall, it seems like a pretty "meh" investment. The people doing it are the environmental True Believers(tm). I'd rather put the money into a new bathroom at this point.

Re: California Votes to Require Rooftop Solar Power on New Homes

#35

Earlier quoted context omitted.

Expensive compared to what? CO2 emissions? You already get a 30% federal tax credit as well as CA state and local utility incentives, what more is necessary? A free system? I agree a carbon tax would be ideal. It seems politically impossible though, so you achieve what you can.

That was a response to your statement that the relevant research has been done. I don't think it has. We still have to figure out ways to lower the cost of storage. You're saying it is cheap enough that we can now mandate it? It should be cheap enough when purely green energy is superior to any other source. Solar alone is cheap, but not solar + storage.

[deleted]

Re: California Votes to Require Rooftop Solar Power on New Homes

#36
post #7

Good night. Once upon a time in 1983, my grandparents bought a mobile home and put it out on rural property. They paid $300 for the water company to install a water meter and about $1500 for a septic tank install. Now I'm trying to do the same thing (and on the same property). The water meter is $5,000 (cash only in full), and the septic tank is $15,000. If I was also required to have solar, I'd really be screwed...…

Just in case anyone was curious (I was) $1500 in 1983 is $3758.34 in 2018

Re: California Votes to Require Rooftop Solar Power on New Homes

#37
post #3

Saw this in my rss this morning: https://marginalrevolution.com/marginalrevolution/2018/05/ro... > I just became aware in the last few days of the proposal in the new building energy efficiency standards rule making to mandate rooftop solar on all new residential buildings. I want to urge you not to adopt the standard. I, along with the vast majority of energy economist, believe that residential rooftop solar is a mu…

I doubt this is accurate. Most California homeowners can save money by going 100% off grid vs. 100% grid which suggests home solar + battery is cheaper than an same panels - increased efficiency + electricity distribution system + billing.

That said, currently it's usually cheaper to stay grid connected vs 100% solar. But, the economics of that can shift around as solar becomes more common.

Re: California Votes to Require Rooftop Solar Power on New Homes

#38
post #27
post #19

Earlier quoted context omitted.

On average, it might even save a homeowner money after about 10 years. But I'd much rather leave the decision up to the relevant people instead of mandating this at the state level. If it makes sense to build it, I trust they already would have (as many do), and there will always be exceptions (e.g. shade) where the mandate will be perverse.

At that price it should save money after one year. But you’re right to care about perverse incentives; it’s hard for governments to get that right for the same reason it’s hard to make an AI that doesn’t reward hack.

One year? Someone up the page said theirs would take 8 years to pay for itself, and the article says:

Installing a solar system and complying with other energy-efficiency measures required will add about $9,500 to the cost of a new home, according the the California Energy Commission. That would be offset by about $19,000 in expected energy and maintenance savings over 30 years, the commission estimates.

Re: California Votes to Require Rooftop Solar Power on New Homes

#39

So I guess putting up shade trees to reduce cooling costs isn't a thing any more? Is it net positive to use solar panels? Trees and houses just won't go together any more?

> So I guess putting up shade trees to reduce cooling costs isn't a thing any more?

Trees are still great for shading windows and unlikely to interfere with panels in that role, and it takes a much bigger and older tree to shade a roof, anyway.

Re: California Votes to Require Rooftop Solar Power on New Homes

#40
I'm having a hard time finding a news article with links to the actual standard, and secondary sources like this Bloomberg article are omitting important details. Does this represent the standard that was adopted:

http://docketpublic.energy.ca.gov/PublicDocuments/17-BSTD-01...

?

In particular, I wonder what the minimum system size is, in kilowatts. Reporting household system size in "dollars" is a poor metric because PV dollars-per-watt is changing rapidly.

The source that I linked above says "Minimum PV sizing by code will rely on results from the energy consultant’s Title 24 compliance calculations." Can anyone explain what's required to comply with Title 24? I'm looking for answers in physical units rather than currency units.

FWIW, Germany and Australia have fully-installed residential rooftop solar costs-per-watt less than half of that in the US. I'm not sure where the big cost gap comes from -- Germany and Australia have decent wages for labor and safety codes too. The hardware is commoditized and globalized. If California could match Australian costs-per-watt then this proposal would add significantly less to the initial cost of a new house and significantly increase lifetime cost savings vs. using only power from the grid.

EDIT: it looks like the final adopted proposal is 17-BSTD-02, rather than the earlier 17-BSTD-01 that I linked above. Here's the final one:

http://docketpublic.energy.ca.gov/PublicDocuments/17-BSTD-02...

The final version says even less about minimum system size. I suppose that detail is hidden in one of the 14 documents it incorporates by reference.

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