What would you do differently if you build a new house with solar panels?

[EL0NTRK]

Knowing what you know now, what would you do when you plan the new build. Solar roof is not a consideration due to cost, etc.
How would you run the conduit on the attic down to the electrical panel in the garage?
How would you layout the roof, vents to maximize panels?
How you arrange your electrical panels in the garage so you can do the Power Wall, inverters, etc?
Etc, etc.

 

[oktane]

Solar roof might not be that much more than a regular roof + solar.

I'd make sure the roofers do the screw penetrations and recess the panels so they are flush with the roof (shingles where the panels go and tiles elsewhere).

I'd leave wall space for a power wall and make sure to have a separate critical load panel that can be powered by a powerwall or generator.

 

[Ampster]

As mentioned, I would consolidate plumbing vents on North facing pitches to maximize South facing roof area.

 

[miimura]

I did solar with my custom home construction. I am very happy with the results, but I wish I had gone bigger on the array. This was 2012, so the $/kW was much higher than today. I told the GC to keep all the SE and SW facing roof areas clear of any roof penetrations. The solar installer put the racking supports and junction boxes on the roof before the roofer did their install. My system uses micro-inverters and there is no external wiring visible. The two solar circuits are plain romex in the attic and walls. Since there is no high voltage DC, there is no need for conduits or disconnects. It's all very clean.

 

[h2ofun]

I did solar with my custom home construction. I am very happy with the results, but I wish I had gone bigger on the array. This was 2012, so the $/kW was much higher than today. I told the GC to keep all the SE and SW facing roof areas clear of any roof penetrations. The solar installer put the racking supports and junction boxes on the roof before the roofer did their install. My system uses micro-inverters and there is no external wiring visible. The two solar circuits are plain romex in the attic and walls. Since there is no high voltage DC, there is no need for conduits or disconnects. It's all very clean.

View attachment 716398

I have yet to hear from a person who wished they had put on a smaller array

 

[holeydonut]

I have yet to hear from a person who wished they had put on a smaller array

Just wait until PG&E bribes the CPUC directors and NEM 3.0 comes out exactly as the joint IOU submission requests...

PG&E is going to


BTW on paper a Tesla Solar Roof V3 is amazeballs for a new construction. Long lasting roof that also produces electricity. We all wish Tesla and it's independent subs were more reliable and the roof could be delivered on the tight deadlines required of new home build.

 

[miimura]

Just wait until PG&E bribes the CPUC directors and NEM 3.0 comes out exactly as the joint IOU submission requests...

PG&E is going to


BTW on paper a Tesla Solar Roof V3 is amazeballs for a new construction. Long lasting roof that also produces electricity. Just wish it was more reliable and able to be delivered on the tight deadlines required of new housing starts.

This is what I want to know: If I add more solar and get bumped from NEM1 to NEM2, will I only get 20 years of NEM2 from my original PTO in 2012 or will I get a new 20 years from the new install date? I suspect it's the former.

 

[h2ofun]

This is what I want to know: If I add more solar and get bumped from NEM1 to NEM2, will I only get 20 years of NEM2 from my original PTO in 2012 or will I get a new 20 years from the new install date? I suspect it's the former.

I thought I heard 20 years total, no reset to 20, but, ....

 

[holeydonut]

This is what I want to know: If I add more solar and get bumped from NEM1 to NEM2, will I only get 20 years of NEM2 from my original PTO in 2012 or will I get a new 20 years from the new install date? I suspect it's the former.

Obviously my opinion could be very wrong, but my understanding is if you added panels right now and got your system re-PTO'd under NEM 2.0... you'd just be a new NEM 2.0 customer and get 20 years from today.

So yeah, you would need to decide if it's worth it to lose the juicy NEM 1.0 policies and near-zero NBCs to go to NEM 2.0 and lock that in for 20 years at a slightly lower solar benefit. Because if you add panels after NEM 3.0 you could be looking at moving your array to this NEM 3.0 rate structure:

(Estimated by the Sage Energy Consulting after they reviewed the Joint IOU submission). This doesn't take into account the negative/penalty fee layered on top of the rates that would be charged for kWh exports to the grid around noon.

 

[gpez]

I'd plan a location of the equipment better. More jurisdictions are considering or implementing (for better or worse) fire prevention and detection requirements. Pre-run routes for cabling, central location for things like inverters and batteries (with ventilation and fire considerations), and plenty of room for expansion or changes.

 

[charlesj]

I have yet to hear from a person who wished they had put on a smaller array

I want a smaller system with much more production though.

There you go.

 

[miimura]

I want a smaller system with much more production though.

There you go.

I want a "Mr. Fusion".

There you go.

 

[wwhitney]

As mentioned, I would consolidate plumbing vents on North facing pitches to maximize South facing roof area.

And design the house with maximum south facing roof planes, e.g. a saltbox. Or maybe some north facing clerestory windows.

On the electrical, no all-in-one meter/disconnect/distribution. Just a meter/disconnect, with a separate feeder to the load panel(s). Leave room for a GW2 between the meter/disconnect and the load panel(s), along the run of the feeder and near the panel(s). If you know ahead of time that if you get backup power you want some loads backed up, and some other loads not, segregate the loads into two different panels.

PW+ eliminates the need for some of the above restrictions, but it has its own limitations.

Cheers, Wayne

 

[johnnyS]

Our system matches our use the year before installation. If we were doing it now, I would go for a bigger system with battery backup.

 

[getakey]

With PG&E, bigger is not always better. If you become a net producer, you get pennies for over production. Thus, there is no ROI on the excess panels. I guess you could add more electrical devices or an EV

 

[holeydonut]

With PG&E, bigger is not always better. If you become a net producer, you get pennies for over production. Thus, there is no ROI on the excess panels. I guess you could add more electrical devices or an EV

I'm still waiting for the big EV charging party hosted at @h2ofun 's house.

 

[h2ofun]

With PG&E, bigger is not always better. If you become a net producer, you get pennies for over production. Thus, there is no ROI on the excess panels. I guess you could add more electrical devices or an EV

That is the point. Many when get solar add stuff they never thought about. One EV and well, ....

 

[BGbreeder]

With PG&E, bigger is not always better. If you become a net producer, you get pennies for over production. Thus, there is no ROI on the excess panels. I guess you could add more electrical devices or an EV

Don't forget that given the degradation over the life of the panels, you will have lower production as time goes on. So, lower, but not zero ROI on the "excess" panels. Unless the home is 100% electric going in, count on more demand, and even if it is, I would bet on demand increasing just from more "need to haves". (Look at photos from homes thirty years ago, and see all the things that we have that they didn't.)

x2 on @wwhitney's comments. I would also vote for a meter/disconnect separate from the main panel, which I would oversize, with space in between for a gateway, and a transfer switch, with conduit out to a concrete yard wall ornament that could be used as a Powerwall island. Ok, maybe I wouldn't build the concrete wall yard ornament, but I would make the wall with the Powerwalls on it with extra fireproofing on the wall and above them, and I would put in a layer of intumescent paint., if it wasn't bare concrete.

And yes, you can't have too many panels.

All the best,

BG