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What's the best TOU plan w/SDG&E w/solar on house & M3

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I have an M3 that I charge exclusively at home. Just got solar for my house a few months ago. My electricity provider is SDG&E. Currently I am on the EV-TOU-5 electric plan.It was the best plan for me before I got the solar because, even though there is a $16 monthly service charge on that plan, the .09 on super off peak, which is when I charge the M3, more than makes the service charge worthwhile. The comparisons online based on my usage before I got solar for the house shows this plan was, by far, the best one for me.

But with solar on the house, the net metering does not allow that service charge to be paid with generated electricity. Therefore, I would need to pay it with whatever credit I have at the end of my year when the true up occurs. But you only get credit for any over generation of electricity at .03 - .04 at true up. If you take the midpoint of that - .035 - that would mean it would take 457 KWh a month to cover that which is a ton. I'm thinking I should move to another TOU plan that doesn't have a service charge on it. EV-TOU-2 seems like a candidate plan for me. I'm waiting for my first all solar electric bill in the next couple weeks before making any changes. Are there any others out there in a similar situation I am in? What advice might you have? What did you do? Thanks everyone.
 
I am in the exact same position. My first year of solar and first true-up will be at the beginning of June, but I’ve only had the Tesla since March. With the credits I have from the 9 months prior to charging at home, I have a huge credit. However, during the winter months I eat into that credit a bit. Looking at all of that, the EV-TOU-5 might end up looking better next year with the service charge.
In the end I guess it depends if you are a net over-producer or net user at the end of the year (when you include the additional load of charging at home). Over-producer would be better off at EV-TOU-2 because there is no service fee. Net user would probably be better on EV-TOU-5...but not in all cases. So, I guess I’ll just go this year and know I might have to eat the $192 in service fees at the end of it.
I guess my advice...or my plan...is to just see after this year. In the grand scheme of things, $16/month to drive an EV is still way better than what gas would cost. (But the penny-pincher in me would love to pay SDG&E ZERO for my power!)
 
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I can help (have solar, AC, two EVs, and work at SDG&E in the Clean Transportation group)...

I think the most important question to ask from an annual perspective is...Are you a net annual buyer or a net annual seller? With a few exceptions, a net annual buyer does better on EV-TOU5 (because you want to do your buying to charge your EV in the cheaper super off-peak period at 9 cents) and a net annual seller does better on EV-TOU2 (because you avoid the $16 monthly fee of EV-TOU5 and would pay the minimum bill charge of 34 cents per day instead for months when you don't use $10 worth of juice).

My solar system generates slightly more than what I use on an annual basis, and I'm on EV-TOU2.
 
same question with APS in AZ. I Will only have 3.78 kW panels that I'm renting from Tesla so I will be a net buyer. Hoping we don't have to be draconian about the TOU plan (ACs and such, I will continue to charge at night.

Charges for electricity services Amount of electricity used last Aug with minimal charging @ home

Cost of electricity you used
Customer account charge $2.12
Delivery service charge $21.68
Demand charge on-peak - delivery $35.60
Environmental benefits surcharge $4.94
Federal environmental improvement surcharge $0.50
System benefits charge $5.42
Power supply adjustment* $3.25
Metering* $5.83
Meter reading* $2.09
Billing* $2.35
Generation of electricity on-peak* $31.51
Generation of electricity off-peak* $88.68
Demand charge on-peak - generation* $39.16
Federal transmission and ancillary services* $21.52
Peak event monthly discount -$23.82
Federal transmission cost adjustment* $4.94
LFCR adjustor $4.55
Tax Expense Adjustor -$14.21
Cost of electricity you used $236.11
Taxes and fees
Regulatory assessment $0.57
State sales tax $13.52
County sales tax $1.69
City sales tax $7.97
Franchise fee $4.73
Cost of electricity with taxes and fees $264.59
Total charges for electricity services $264.59



Meter reading on Aug 13 43925
Meter reading on Jul 15 41963

Total electricity you used, in kWh 1962
On-peak meter reading on Aug 13 8398
On-peak meter reading on Jul 15 8103
On-peak electricity you used, in kWh 295

(3 pm - 8 pm Monday - Friday)
Off-peak electricity you used, in kWh 1667
(8 pm - 3 pm Monday - Friday and all day on weekends and 10 holidays)

On-peak demand meter reading 8.93
Your billed on-peak demand in kW 8.9
 
I can help (have solar, AC, two EVs, and work at SDG&E in the Clean Transportation group)...

I think the most important question to ask from an annual perspective is...Are you a net annual buyer or a net annual seller? With a few exceptions, a net annual buyer does better on EV-TOU5 (because you want to do your buying to charge your EV in the cheaper super off-peak period at 9 cents) and a net annual seller does better on EV-TOU2 (because you avoid the $16 monthly fee of EV-TOU5 and would pay the minimum bill charge of 34 cents per day instead for months when you don't use $10 worth of juice).

My solar system generates slightly more than what I use on an annual basis, and I'm on EV-TOU2.

I have AC as well as solar and the EV. What you say here confirms exactly what I have been thinking, so that makes me feel good. I'm guessing I will be a net seller because if I extrapolate out the last 6 days left in my current (and first full month of net metering) billing period, I should generate about 165% of average monthly usage based on my trailing 12 months of KWh usage. But I also realize that the days are longer now, I'm using no AC yet, and assuming I move to the EV-TOU-2 plan, which is what I have been guessing is where I will land, there is a .55 during summer for on peak. But I still think I will be a net seller for the year. Based on your experience with your electric generation history so far, do you agree? I am waiting for my first full month under net metering before I decide.
 
Eddie, do you have a Powerwall or other solar battery? I ask because having storage to shift your usage away from peak rates changes the calculus quite a bit. For me, I’ve basically never pulled power from the grid during peak (4-9) because the Powerwall supplies me during this period. If you don’t have storage, then that higher peak cost might make EV-TOU-5 more practical for the entire year.
 
eddieb3,
If you have only been a net metering customer for 1 month, I'm assuming that your solar PV system is about that old as well. When you were working with your solar contractor, did they provide an estimate with your paperwork on how many kWh you would generate annually? Did you tell them you wanted the system to match your annual consumption, or some percentage of that?

It's tough to extrapolate your annual production with one month's worth of real data, because there is such variation over the year. The Spring time is typically when you would over generate the most since the sun is pretty strong and you're not using much AC.

Sounds like you know what your consumption is for a typical year, so we'd just want to figure out what your generation will be and then go from there....How many panels did you get?
 
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Eddie, do you have a Powerwall or other solar battery? I ask because having storage to shift your usage away from peak rates changes the calculus quite a bit. For me, I’ve basically never pulled power from the grid during peak (4-9) because the Powerwall supplies me during this period. If you don’t have storage, then that higher peak cost might make EV-TOU-5 more practical for the entire year.
Nope, no power wall.
 
eddieb3,
If you have only been a net metering customer for 1 month, I'm assuming that your solar PV system is about that old as well. When you were working with your solar contractor, did they provide an estimate with your paperwork on how many kWh you would generate annually? Did you tell them you wanted the system to match your annual consumption, or some percentage of that?

It's tough to extrapolate your annual production with one month's worth of real data, because there is such variation over the year. The Spring time is typically when you would over generate the most since the sun is pretty strong and you're not using much AC.

Sounds like you know what your consumption is for a typical year, so we'd just want to figure out what your generation will be and then go from there....How many panels did you get?

It’s an 8.75 kW system. Electric generation is estimated at 13,613 kWh. My trailing 12 previous months usage was 11,729. Twenty-five 350 kW panels. We will probably use more electric because we will use AC more than before solar. But on the other side, 30% - 40% of the usage is charging the EV which would cost .193 on the EV-TOU-2 plan while the generation of kW with the solar panels will all happen using higher rates.
 
Ok, sounds good. From all you've told me, I would try the EV-TOU2 rate the first year and see how that goes. You can always switch to EV-TOU5 after the first year if you think you'll be buying more energy.

Another point to keep in mind...You're buying and selling in any given day. Yes, EV-TOU5 has a great price for charging in super off-peak. But that's also the super off-peak price you'll get for your generated energy until 2pm on weekends and in March-April from 10am to 2pm. So EV-TOU5 does mean a reduced selling price for a percentage of the time over the year that EV-TOU2 doesn't have (because the super off-peak isn't as low).

There is a tool on the SDGE website within the MyInfo section that will estimate what the best rate is for you. The only thing is that it bases its recommendation on your past 12 months worth of history, which you don't have in place yet.

So my recommendation would be to try EV-TOU2 for the first year and then as you get towards the end of it, run the tool and see if any other rate would be better for you...

Another point: If you switch your rate, it usually happens at the end of your next billing cycle. So depending on when you apply, the change takes place at the next billing cycle and then you don't get the first bill on that rate until the next billing cycle after that...

Sounds like you are in good shape with your solar PV system and your EV....Congrats!
 
Ok, sounds good. From all you've told me, I would try the EV-TOU2 rate the first year and see how that goes. You can always switch to EV-TOU5 after the first year if you think you'll be buying more energy.

Another point to keep in mind...You're buying and selling in any given day. Yes, EV-TOU5 has a great price for charging in super off-peak. But that's also the super off-peak price you'll get for your generated energy until 2pm on weekends and in March-April from 10am to 2pm. So EV-TOU5 does mean a reduced selling price for a percentage of the time over the year that EV-TOU2 doesn't have (because the super off-peak isn't as low).

There is a tool on the SDGE website within the MyInfo section that will estimate what the best rate is for you. The only thing is that it bases its recommendation on your past 12 months worth of history, which you don't have in place yet.

So my recommendation would be to try EV-TOU2 for the first year and then as you get towards the end of it, run the tool and see if any other rate would be better for you...

Another point: If you switch your rate, it usually happens at the end of your next billing cycle. So depending on when you apply, the change takes place at the next billing cycle and then you don't get the first bill on that rate until the next billing cycle after that...

Sounds like you are in good shape with your solar PV system and your EV....Congrats!

Thanks for the advice. Kinda forgot about the super off peak going til 2 PM on weekends and holidays. Didn't know about the 10 AM - 2 PM thing during March and April. When I look at the TOU plans here: Time of Use (TOU) | San Diego Gas & Electric I don't see anything that defines what peak, off peak, etc. times are. Do you know where I can find that on the site?

I think I will change to the EV-TOU-2 plan.Was going to wait until I saw my first full bill, but if it takes the bill after the next one before it changes, I'm going to do it now. Thanks again!
 
same question with APS in AZ. I Will only have 3.78 kW panels that I'm renting from Tesla so I will be a net buyer. Hoping we don't have to be draconian about the TOU plan (ACs and such, I will continue to charge at night.

Charges for electricity services Amount of electricity used last Aug with minimal charging @ home

Cost of electricity you used
Customer account charge $2.12
Delivery service charge $21.68
Demand charge on-peak - delivery $35.60
Environmental benefits surcharge $4.94
Federal environmental improvement surcharge $0.50
System benefits charge $5.42
Power supply adjustment* $3.25
Metering* $5.83
Meter reading* $2.09
Billing* $2.35
Generation of electricity on-peak* $31.51
Generation of electricity off-peak* $88.68
Demand charge on-peak - generation* $39.16
Federal transmission and ancillary services* $21.52
Peak event monthly discount -$23.82
Federal transmission cost adjustment* $4.94
LFCR adjustor $4.55
Tax Expense Adjustor -$14.21
Cost of electricity you used $236.11
Taxes and fees
Regulatory assessment $0.57
State sales tax $13.52
County sales tax $1.69
City sales tax $7.97
Franchise fee $4.73
Cost of electricity with taxes and fees $264.59
Total charges for electricity services $264.59



Meter reading on Aug 13 43925
Meter reading on Jul 15 41963

Total electricity you used, in kWh 1962
On-peak meter reading on Aug 13 8398
On-peak meter reading on Jul 15 8103
On-peak electricity you used, in kWh 295

(3 pm - 8 pm Monday - Friday)
Off-peak electricity you used, in kWh 1667
(8 pm - 3 pm Monday - Friday and all day on weekends and 10 holidays)

On-peak demand meter reading 8.93
Your billed on-peak demand in kW 8.9

Wow having solar now in Phoenix area is such a ripoff now. We have a 6kw solar system but we got it back in 2013 so we are grandfathered in for the net metering plus no on demand charge. Our bill last August was $134.80 that was for 2208kwh off peak and 307 on peak. We produced 947 off peak and 227 on peak but we had excess on peak kWh built up so no charge for on peak charges. Actually we haven’t paid for on peak charges since we have had solar panels. We are under SRP and we lease our panels ($114/month). So this was our biggest bill for the year so $245 for the hottest month in Phoenix for a 3000sq ft house is pretty good. If we got solar now our bill would be so much higher with how SRP and APS charges for on demand peak charges which in my opinion has ruined residential solar here in Arizona.
 
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Wow having solar now in Phoenix area is such a ripoff now. We have a 6kw solar system but we got it back in 2013 so we are grandfathered in for the net metering plus no on demand charge. Our bill last August was $134.80 that was for 2208kwh off peak and 307 on peak. We produced 947 off peak and 227 on peak but we had excess on peak kWh built up so no charge for on peak charges. Actually we haven’t paid for on peak charges since we have had solar panels. We are under SRP and we lease our panels ($114/month). So this was our biggest bill for the year so $245 for the hottest month in Phoenix for a 3000sq ft house is pretty good. If we got solar now our bill would be so much higher with how SRP and APS charges for on demand peak charges which in my opinion has ruined residential solar here in Arizona.

yeah I'm just hoping it will take the edge off and 3.8Kw will atleast power the AC so I don't have to supercool and worry about 3-8pm
 
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