The best way to install solar panel with EV

[kevinpal]

Hi All,
I am wondering what's the best way to maximize the profit of solar power usage with EV( tied to grid ).
I guess the best way is to have one meter with EV charger connected and charge it at off peak hour.
But I have separated EV account(Second meter and physically connected with another power line) with SEC.
If I apply the credit(over produced) to second meter(EV account), it is not exactly one to one price because of non-bypassable charges(NBCs) and
I am worried about that they might change the NEM2.0 rule in the future.
So Is it better to have one meter with connected EV charger and charge it at off peak hour?
Does anyone get same situation(2 separated accounts one for EV, one for home)?
Thanks.

Kevin

[Ampster]

To answer your question I would need a lot more information about the rate plans that are available and your consumption patterns and forecast. For example , how much your house consumes (in kWhr) and when it is consumed relative to the rate periods of peak, mid peak and off peak? How many kWhrs you might be charging your EV? A simple rule of thumb is to divide miles driven by 3 to get kWhrs unless you are also using remote charging. What size system you are thinking of installing and an what is a reasonable estimate of annual production based on location and installation.

I assume you are in California? Do you mean SCE instead of SEC? Most people I know with solar and EVs use a single meter. I tried a pilot program for a separate EV charging meter and it did not work for me. Your mileage may vary depending on the above assumptions.

For my planning purposes i am assuming rates are going to go up, there is going to be a larger fixed component to rates and the time periods favorable for solar generation are going to continue to shift. NBCs don't effect me as much because the majority of my net consumption is at off peak rates. To me all of my assumptions about the future of pricing has led me to conclude that self consumption in California may be more economical than currently is the case. If you have the resources you may consider upgrading your service panel and separating critical loads so you have the flexibility of adding load shifting batteries when prices come down.

[J.P.M.]

Who is your POCO ?

Do you have PV now ?

What is your lowest per kWh rate and at what time(s) ?

What did your POCO say/suggest/mandate when you called and asked them ?

I'm not sure it's possible to maximize profit from solar power usage. Minimize the cost of providing electrical power to a residence maybe.

[Ampster]

......
I'm not sure it's possible to maximize profit from solar power usage. Minimize the cost of providing electrical power to a residence maybe.

If one defines profit as the return on capital employed it is possible to maximize profit. Perhaps that is what the OP meant? I agree it is not possible to maximize profit on USAGE.

[J.P.M.]

If one defines profit as the return on capital employed it is possible to maximize profit. Perhaps that is what the OP meant? I agree it is not possible to maximize profit on USAGE.

I'm not going to get into the usual waste time with you by quibbling about when/how employing/spending assets to reduce an expense turns into revenue or how those two things contribute to making a profit.

But, I will say that since most definitions of profit, at least by inference if not definition are with respect to a business activity, and this appears to be a residential application - not a business - I'd suggest the word "profit" may be inappropriate.

Still, I was incomplete in my last post.

I should have added : "... in a residential application operating under an NEM agreement with a power provider".

Since the OP is concerned about future changes to NEM 2.0, I inferred that's' what he's operating under now, or plans to operate under in the future. Whether or not the OP currently has PV or is considering it, or considering some change(s) in his current setup was unclear to me from his post.

In any case, and with respect to what looks to me to be your confusion about the difference between minimizing an expense, or maximizing a revenue, and how all that works to realizing/maximizing a profit, I'd say given that at least part of the idea behind NEM - at least everything I've seen/read/heard on the subject, and at least with respect to residential applications - is to provide a workable way to offset some portion of electric bills via onsite alternate energy generation with an interface with the grid rather than to enable for profit power production, the word profit may be a less than fitting word.

As for maximizing revenue, I'm not sure how many homeowners bought their residence with the idea that the property is a revenue producing enterprise in the first place.

Take what you want of the above. Scrap the rest.

[Ampster]

I'm not going to get into the usual waste time with you by quibbling about when/how employing/spending assets to reduce an expense turns into revenue or how those two things contribute to making a profit.
.......

Don't take it so personal. This is not about you.

I wasn't confused at all. I was agreeing with what you were saying about profit on USAGE. That is why I emphasized USAGE so readers would understand I was distinguishing between profit on that and profit on GENERATION, or as you prefer, Inverting from DC.

[kevinpal]

To answer your question I would need a lot more information about the rate plans that are available and your consumption patterns and forecast. For example , how much your house consumes (in kWhr) and when it is consumed relative to the rate periods of peak, mid peak and off peak? How many kWhrs you might be charging your EV? A simple rule of thumb is to divide miles driven by 3 to get kWhrs unless you are also using remote charging. What size system you are thinking of installing and an what is a reasonable estimate of annual production based on location and installation.

I assume you are in California? Do you mean SCE instead of SEC? Most people I know with solar and EVs use a single meter. I tried a pilot program for a separate EV charging meter and it did not work for me. Your mileage may vary depending on the above assumptions.

For my planning purposes i am assuming rates are going to go up, there is going to be a larger fixed component to rates and the time periods favorable for solar generation are going to continue to shift. NBCs don't effect me as much because the majority of my net consumption is at off peak rates. To me all of my assumptions about the future of pricing has led me to conclude that self consumption in California may be more economical than currently is the case. If you have the resources you may consider upgrading your service panel and separating critical loads so you have the flexibility of adding load shifting batteries when prices come down.

Hi Ampster, J.P.M
Thank you for your reply.

Sorry for less information. The annual energy consumption is
HOME: 7095kWh
EV: 3741kWh
TOTAL: 10836kWh

The majority of my net consumption is at off peak based on my home bill.
I usually charge my car after 9pm that's when rate gets lower.
Screenshot_2019-11-16 home pdf.png

I already installed 5.280kW system size. The utility company is SCE(Yes. I live in California).
So I should have just one meter with home and EV? I am not exactly sure but the reason I have completely separated account is
because of my property limitation. I have detached garage and they could not wire between house and garage for EV?
I am talking to solar company right now. They have not submitted the NEM aggreement to SCE yet. They are figuring out right now.
The problem is that they said that the solar can supply power for both home and EV bc EV is connected with sub-panel but it looks like that the EV is physically separated account(getting a line independently from main bc I see a line coming to my garage from the utility pole )so the solar system is not connected at all. That's what I am guessing now.
Can you tell me why your separated account did not work, please?
Thank you.

-Keivn

[Ampster]

..........
So I should have just one meter with home and EV? I am not exactly sure but the reason I have completely separated account is
because of my property limitation. I have detached garage and they could not wire between house and garage for EV?
I am talking to solar company right now. They have not submitted the NEM aggreement to SCE yet. They are figuring out right now.
The problem is that they said that the solar can supply power for both home and EV bc EV is connected with sub-panel but it looks like that the EV is physically separated account(getting a line independently from main bc I see a line coming to my garage from the utility pole )so the solar system is not connected at all. That's what I am guessing now.
Can you tell me why your separated account did not work, please?
Thank you.

-Keivn

The answer to your question of why my separated account did not work is simple. I was NOT getting credit on the separated account for the power I was generating on the regular account. As I mentioned it was a pilot program and the cost was only $45 for the JuiceNet box that measured the EV charging and sent the data to SCE, That box was easy to install and it gave me useful information about my charging and that is one of the reasons that I signed up. A lower rate was offered and I erroneously assumed it would be a subset of my main account based on the description of the pilot program on another forum. That poster figured out his mistake at the same time I figured it out. The lesson is I should have verified what I read on the Internet from an anonymous poster. That was four years ago and since then I have moved to another home and purchased a full Clipper Creek EVSE with JuiceNet firmware. . It not only gives me consumption by vehicle but I can program it from my phone and vary the charging rate depending on my NEM strategy.

I have mentioned what I think the outlook is for rates. As fixed charges become more prevalent I think having two meters could be costly. In your case the cost of running cable to your separate garage has to be weighed against the prospective savings of having it all on one meter.

[kevinpal]

The answer to your question of why my separated account did not work is simple. I was NOT getting credit on the separated account for the power I was generating on the regular account. As I mentioned it was a pilot program and the cost was only $45 for the JuiceNet box that measured the EV charging and sent the data to SCE, That box was easy to install and it gave me useful information about my charging and that is one of the reasons that I signed up. A lower rate was offered and I erroneously assumed it would be a subset of my main account based on the description of the pilot program on another forum. That poster figured out his mistake at the same time I figured it out. The lesson is I should have verified what I read on the Internet from an anonymous poster. That was four years ago and since then I have moved to another home and purchased a full Clipper Creek EVSE with JuiceNet firmware. . It not only gives me consumption by vehicle but I can program it from my phone and vary the charging rate depending on my NEM strategy.

I have mentioned what I think the outlook is for rates. As fixed charges become more prevalent I think having two meters could be costly. In your case the cost of running cable to your separate garage has to be weighed against the prospective savings of having it all on one meter.

Thank you for your reply.
Yes. I am not even sure if it is eligible to apply credit to my second account.
I will look into how much it would cost to run a cable to my garage and go from there.
Thank you.

-Kevin

[Ampster]

.........
I will look into how much it would cost to run a cable to my garage and go from there.
Thank you.

-Kevin

If you are into doing some of the grunt work look at some of the posts by @bcroe. I am too old to be digging ditches but trenching machines can be rented cheap and casual labor is plentiful in California. I don't like to pay electrician rates to cement conduit together and put it in a trench. There may be a lot of reasons in the future that you may want a sub panel in that garage anyway. That could be especially true if you are planning to stay there a while.

[kevinpal]

If you are into doing some of the grunt work look at some of the posts by @bcroe. I am too old to be digging ditches but trenching machines can be rented cheap and casual labor is plentiful in California. I don't like to pay electrician rates to cement conduit together and put it in a trench. There may be a lot of reasons in the future that you may want a sub panel in that garage anyway. That could be especially true if you are planning to stay there a while.

Yes. I think that's why they installed EV meter separately bc digging ditches and running cables cost a lot. But I will look at @bcroe's post.
Thank you.

[Ampster]

Yes. I think that's why they installed EV meter separately bc digging ditches and running cables cost a lot. But I will look at @bcroe's post.

You think that is why? Did some of this get done before you were involved? Running lines from the pole to a separate meter can also be expensive.

Do you have a rough plot plan or some aerial view that would give the readers a better sense fo the layout? A real value of forums like this is to learn from the mistakes that others make.

I am not suggesting that there were any mistakes made on your property but depending on where one is standing there may be a different view on how to solve a problem.

[kevinpal]

I think so. Actually SCE run the lines to my garage when I installed EV. but I only paid for permission fee.
I think they are happy to to do that bc they can make more money by adding EV account.
This is my property layout. The problem is that the ground between my house and garage is all concrete. The red lines are the power lines.
house.jpg

[Ampster]

Well, that makes it more expensive to consolidate the two meters. Thanks for the plot plan.

There is a NEM tariff with SCE that allows you to aggregate two meters with contiguous parcels. I an using it on some commercial property I have on SCE meters in Hermosa Beach. It doesn't save me anything on the fixed charges but at least my solar generation credits offset most of the charges on the other account. Look on SCE's website for Virtual Net Metering.

As to the original question. Perhaps your installer gave you an estimate of annual production. I would guess in perfect conditions you might generate between 6,000 to 7,500 kWhrs per year which will not offset your consumption. To see what your existing system might produce and model what additional solar might contribute go to PV Watts. Do you have more south facing roof area on either building?

[bcroe]

Yes. I think that's why they installed EV meter separately bc digging ditches
and running cables cost a lot. But I will look at @bcroe's post. Thank you.

With all the hassle of renting, hauling, scheduling, and cleaning up trenchers, I finally just broke
down and paid 3 grand (free delivery) for my own, to be used at my convenience. This is 18 inch,
but now a 24 inch is the same price. Mine was not self propelled, but I fixed that with a winch
which pulls it along just fine. Bruce Roe

Trench2.JPG