POLL: Do you have an EV and also home solar PV?

[Skotty]

My wife and I don't directly tie our interest in rooftop solar to having an EV, but having an EV does help encourage it. While it was always a tentative plan, we have committed to solid dates as part of our personal Paris Pledge to install rooftop solar before year end 2018. Despite less favorable economics, it is even more important for people in places like I live to push for renewable energy, given the high percentage of coal use for utility power.

Anyone considering it should be aware that the federal tax credit (ITC) for solar begins to decline after 2019. While deep concerns remain given the admiinistration's direction on environmental protection, at the moment the ITC does not appear to be under any threat of early termination. However, it would be a good idea to check for this each federal budget year.

 

[rxlawdude]

We put a 6.7kW system in in February 2015. After that was up and running, it was an easier sell to get a BEV and sell the Plug-in-Prius.

With Southern California Edison, one must be very careful to study which plan works best. We got our 70D in July 2015, and August and Sept electric consumption (between A/C and the fact I drive the MS 100mi/day) was shockingly expensive under the tiered (default) residential plan, in spite of significant solar generation.

A pilot program that allowed a "submeter" on the EVSE, with EV rates (around $.12/kWh off peak) helped a lot, but there were lots of problems between the utility and the company that read and reported the submeter usage, so it wasn't till February of 2016 that we saw the full effects of the submeter. At that point, the whole-house was still on the tiered plan.

When the pilot expired, we just switched the whole-house to TOU-D-B, with off-peak rate of $.13/kWh. Ironically, the new TOU-EV rate (that we'd have if we continued the submeter approach) is now $.14/kWh off peak!

 

[SMAlset]

Our house still has a number of years left on the roof so right now no and we're using a NEMA 14-50. The Tesla roof tiles are something we're interested in and I like the cleaner, obscured look of them. Something to think about for sure. Really don't want to put panels up in concrete roof tiles we have now.

 

[rays427]

That's way more seasonality than I would have expected, especially in California. With my old panels, 700 W, my worst month was December 2010 with 45 kWh and my best month was May 2012 with 127 kWh, less than a 3X difference. With my current 2170 W array my worst month was January 2017 with 157 kWh and my best month was June 2013 with 356 kWh, about a 2.3X difference. I can, and do, adjust my pitch with the seasons but, even so, I wouldn't expect so much seasonality for fixed pitch panels except very far north. Do you have shading issues?

We live in the foothills between Sacramento and Lake Tahoe. We have 4 sets of panels with only one set facing south the others face east and west. We get some shading from large trees plus we get a lot of rain in the winter and virtually none in the summer. Average rainfall is about 55 inches although this year it was around 90 inches.Our daily output has ranged from 63 Kwh to under 2 Kwh.

 

[Jaff]

Did having an EV drive you to solar, or are you someone who would have gotten solar even without an EV? I am trying to figure out how much solar demand is going to be driven by 500,000 Model 3s in the wild over the next year or so.

That's a good question...we've had at least one Tesla since 2010...back then, we were much more concerned with driving an EV...for us, the solar piece just fell into play this year...I think we would have done solar at some time in the future, but I'd definitely say that driving EVs for so many years expedited the decision.

 

[303JeffB]

The question then becomes, did having an electric car push you into solar, or had you planned on solar all along?

Good question - I have been considering/investigating solar for a number of years, but the EV provided the final piece that made it a no-brainer from my perspective.

 

[CmdrThor]

I lied and said I had panels already but I wont have them until next month. So sue me. Interesting results, wish more people voted. Also, would be interesting to know if the reason people who said no was because they cant put panels on their condo or town home because of the association or they are renting.

I think a lot of people who don't have solar haven't bothered voting so the poll is pretty useless. People who have solar and see solar in the title of the thread are more likely to open it and vote.

I voted no because solar is not viable for my home. Google Solar Project estimates a 16 year payback period. Savings of $4k after 20 years on a $16k initial investment. That's a pretty terrible ROI, I could invest the money instead and be much better off.

 

[Reciprocity]

Good question - I have been considering/investigating solar for a number of years, but the EV provided the final piece that made it a no-brainer from my perspective.

I think as big of a push that EVs will have for solar, especially households with 2 EVs, I think fully Autonomous EVs is going to push EVs even more then the environmental or even the economical reasons. And that will intern push even more solar. The Autonomous EV vs Autonomous ICE is so unfairly balanced to the EV that there really is no reason to make an ICE car self driving. Sure, there will be some exceptions, but for the masses, self driving EVs absolutely crush ICE, especially when you factor in Solar. Once you remove the cost of the driver in say a ride sharing network, you are left with Fuel and Maintenance. Assuming the costs of the cars are similar, the fuel costs are 1/4th or even less with solar. Maintenance on an EV drive train that is good for a million miles vs a an ICE engine.. This is critical for cars that drive hundreds of miles per day. I dont know the exact amount but something like 20c a mile for EV vs 80c/mile for ICE. Who is going to buy an autonomous ICE vehicle that costs 4x as much to use? Can you imagine the residual value of your Model 3? I could imagine fleet owners buying HW2 model 3's at a premium just to put them into autonomous networks. Even if you never paid for FSD, they will gladly pay that fee. That is also the reason I think ever HW2 car will eventually have FSD enabled.

Tesla is going to have to deploy an incredible amount of solar/batteries just for superchargers. Can you imagine a truck stop for Tesla Semis with dozens of 700KWh chargers and even more standard Supercharges? It will be like the Kuwai station for each truck stop. Mind boggling stuff really. In some places, I could even see them using wind. I could see these stations built closer to cities so that they could be duel purpose, selling solar products, cars and even food and entertainment. If you have ever seen photos of large truck stops, think of a miniature Tesla city.

 

[Owner]

Have solar for 10 years, and have completely recouped initial costs.

 

[abasile]

We live in the foothills between Sacramento and Lake Tahoe. We have 4 sets of panels with only one set facing south the others face east and west. We get some shading from large trees plus we get a lot of rain in the winter and virtually none in the summer. Average rainfall is about 55 inches although this year it was around 90 inches.Our daily output has ranged from 63 Kwh to under 2 Kwh.

Like you, we also went ahead and installed PV in spite of significant shading issues. In fact, SolarCity "disqualified" us, essentially saying that their internal policies wouldn't let them install PV on our roof unless we cut back some trees, which I found odd since we were prepared to pay cash. With LA Solar Group and SunPower panels (to maximize the use of our limited roof area), we ended up with a 6.48 kW system and a first-year production guarantee of 7100 kWh, with no tree cutting required. It appears unlikely that we'll hit that target, so LA Solar Group may end up having to install a couple more panels; we'll see.

However, with two EVs, time-of-use electric rates, and generous net metering policies, our system may end up paying for itself within ten years, which seems good enough to justify the investment. It's also a pleasure to be able to support the renewable energy industry. Plus, adding a Powerwall 2 should enable us to generate and consume our own energy during grid outages and during the peak evening hours. I really like the idea of achieving a level of energy independence.

 

[bakerboy]

We put a 6.7kW system in in February 2015. After that was up and running, it was an easier sell to get a BEV and sell the Plug-in-Prius.

With Southern California Edison, one must be very careful to study which plan works best. We got our 70D in July 2015, and August and Sept electric consumption (between A/C and the fact I drive the MS 100mi/day) was shockingly expensive under the tiered (default) residential plan, in spite of significant solar generation.

A pilot program that allowed a "submeter" on the EVSE, with EV rates (around $.12/kWh off peak) helped a lot, but there were lots of problems between the utility and the company that read and reported the submeter usage, so it wasn't till February of 2016 that we saw the full effects of the submeter. At that point, the whole-house was still on the tiered plan.

When the pilot expired, we just switched the whole-house to TOU-D-B, with off-peak rate of $.13/kWh. Ironically, the new TOU-EV rate (that we'd have if we continued the submeter approach) is now $.14/kWh off peak!

We're right in the middle of our 21 panel, 7.35kw system installation and our installer studied our last bill because it was a full month of having our MS, we are also on the TOU-D-B plan and our solar installer recommended to switch to the TOU-D-T plan, so I called SCE yesterday and switched our plan. Maybe this might be something you may want to look into to.

 

[rxlawdude]

We're right in the middle of our 21 panel, 7.35kw system installation and our installer studied our last bill because it was a full month of having our MS, we are also on the TOU-D-B plan and our solar installer recommended to switch to the TOU-D-T plan, so I called SCE yesterday and switched our plan. Maybe this might be something you may want to look into to.

Oh no! Minimum TOU-D-T off-peak (when you should be charging) is $.17/kWh. TOU-D-B is $.13/kWh off peak.

TOU-D-T appears to be advantageous for solar customers because it shortens the peak times into more of the sweet spot for maximum solar generation. But you'll be killed on cloudy days because of the $.45/kWh peak rate (OUCH!), and the TOU-DT off-peak prices are a total ripoff.

You might want to look at your generation curve to see when your peak generation is. It will fall off significantly later in the day. I recommend you reconsider staying on TOU-D-B.

 

[bakerboy]

I will, thanks for the info!

 

[RichardC]

We have a 12K array on the roof which has produced around 100,000 kWh since it was installed (about four times the amount of power used to drive our Model Ss 130,000 km).

 

[PatrickCH4313]

We have a 12K array on the roof which has produced around 100,000 kWh since it was installed (about four times the amount of power used to drive our Model Ss 130,000 km).

100'000 kWh in how many years?

 

[Reciprocity]

100'000 kWh in how many years?

5 years?

 

[Zythryn]

5 years?

I would guess 7 in Toronto.

 

[PatrickCH4313]

I would guess 7 in Toronto.

Around 14'000 kWh a year could be realistic!
For the same installation, 12 kWp Solar Array in Switzerland I get 12'000 kWh per year !

 

[OBX John]

Putting in solar was a no-brainer, the Teslas took longer to justify.