Still worth getting a Model 3 if Electricity costs more than Gas?

[Dave EV]

SDGE does not seem to provide a chart that show what time of day I am using power, but I can guess that 80-90% of it would be durring peak
...
The Car's power usage would be roughly 630kWh a month which is close to what our home uses for power.

I believe that you can call up SDG&E and ask them to run your last year of usage data on the EV-TOU2 rate.

The key would be how it compares to the other simulated rates you have - if it's similar - then you can switch to EV-TOU2 when you get your Tesla and charge at night at the lowest rate possible.

How many miles are you planning on driving the Tesla? 630 kWh / mo would be good for at least 1800 mi / month and probably 2000-2200 mi / month.

The hourly usage data is available on the sdge.com website. Go to:

My Energy -> My Energy Overview. Look for the little chart titled "When does My Home Use Energy", at the bottom of the box click on "My Energy Use". From there you can view your daily electricity usage or click on a bar chart and view the hourly data for the day. If you click on the disk icon, you can download detailed data for the last year in CSV format - then if you're handy with Excel you can calculate your rates yourself.

Using a Supercharger on a regular basis only makes sense if the Supercharger is some place close to an area where you spend 30-45 minutes doing something else.

 

[shonline]

I disagree about it being dubunked. It's the only thing you said and I didn't think it needed an explaination.

I limit it due to those on this site that search your history and disagree with all your posts based on a disagreement. Eliminates childishness.

@DrivingRockies

The "long tailpipe" theory was contradicted by a 2001 study sponsored by the US Department of Energy showing that a switch to electric vehicles would result in a 35 per cent net reduction in greenhouse-gas emissions. A 2004 study based on official Californian data suggested that the net reduction could be as high as 67 per cent.

These are just two examples of many research projects on the topic.

So, I'm not sure why you feel it has not been debunked, but as I always caution everyone - know your source and how they get paid...

 

[Dave EV]

Might cost a bit to put in a second meter. Then you could charge at $0.22 a kWh.
Getting more solar is the obvious answer. I take it that's not an option?

Both good ideas - a 2nd meter would allow you to get the EV-TOU rate without affecting your home electricity costs. I have one, but in the end (with solar) it actually ended up being cheaper for me to go whole-house EV-TOU2. Actually, I probably should revisit that now that the peak time periods have changed. I might be able to lock in low rates for the house if my solar keeps me below the baseline allowance every month.

BTW - is it really .43/kWh from midnight to 6am? Wow...

That's on one of the regular non-EV TOU rates. You get up to 130% of your baseline allowance at 0.20/kWh cheaper than that, then the price jumps up 0.20/kWh. If you use a lot of electricity, that makes solar a total no-brainer. The baseline allowance is around 300 kWh / month in Escondido.

 

[Glamisduner]

Both good ideas - a 2nd meter would allow you to get the EV-TOU rate without affecting your home electricity costs. I have one, but in the end (with solar) it actually ended up being cheaper for me to go whole-house EV-TOU2. Actually, I probably should revisit that now that the peak time periods have changed. I might be able to lock in low rates for the house if my solar keeps me below the baseline allowance every month.


That's on one of the regular non-EV TOU rates. You get up to 130% of your baseline allowance at 0.20/kWh cheaper than that, then the price jumps up 0.20/kWh. If you use a lot of electricity, that makes solar a total no-brainer. The baseline allowance is around 300 kWh / month in Escondido.

Yea and the power I pay per year above does not include the $250 a month I pay towards my solar loan. So about $4200 a year for power plus whatever I will pay for the EV.

at 237 Wh per mile
* 80 miles
* $.23 = about $5 a day (I round up because I will be using AC and driving over 60). Not bad!

 

[Daniel in SD]

I might be able to lock in low rates for the house if my solar keeps me below the baseline allowance every month.

SDG&E solar customers can only stay on the tiered plan for five years then you get switched over to TOU. At $.22/kwh the payback time is very quick! $3/watt ~= $2/kwh/year / $.22/kwh ~= 9 years. SDG&E has already applied for another 11% rate increase too.

 

[Dave EV]

Yea and the power I pay per year above does not include the $250 a month I pay towards my solar loan. So about $4200 a year for power plus whatever I will pay for the EV.

But you're already stuck paying your solar loan - so that doesn't factor into your decision at all into buying a Model 3.

If you have solar, one of your options on your "Pricing Plan Options" should have been the DR-SES - I didn't see that in your earlier list - what is the annual estimate for that plan? DR-SES has the same pricing as the EV-TOU rate plans, so you can use that to figure out the effect of an EV on your annual cost.

SDG&E solar customers can only stay on the tiered plan for five years then you get switched over to TOU. At $.22/kwh the payback time is very quick! $3/watt ~= $2/kwh/year / $.22/kwh ~= 9 years. SDG&E has already applied for another 11% rate increase too.

Good point - My system is coming up on 8 years old now so it's already paid for itself. What I need to figure out is how much more solar I can add as my solar system wasn't sized to offset any EVs. Biggest drawback there is that adding more solar will put me into NEM 2.0 rules.

 

[Glamisduner]

But you're already stuck paying your solar loan - so that doesn't factor into your decision at all into buying a Model 3.

If you have solar, one of your options on your "Pricing Plan Options" should have been the DR-SES - I didn't see that in your earlier list - what is the annual estimate for that plan? DR-SES has the same pricing as the EV-TOU rate plans, so you can use that to figure out the effect of an EV on your annual cost.

That's good stuff right there! Thanks for pointing that out! SES is slightly different rates depending on the sub plan but the ones I am interested in appear to be the same. The EV-SES-GF plan looks terrible anyways.
EV Rates -> https://www.sdge.com/sites/default/files/regulatory/1-1-18 Schedule EV-TOU & EV-TOU-2 Total Rates Tables.pdf

SES Rates -> https://www.sdge.com/sites/default/files/regulatory/1-1-18 Schedule DR-SES Total Rates Table.pdf

That last plan fell off the page but it's showing $1399 for DR-SES, so about $200 more than I currently pay per year. It would still be worth going to the EV-TOU plan or DR-SES for sure once I get an EV. It's that or spend some time at a supercharger every other day. For $200 I think it would be worth charging at home though

I hope these current calculations on the site are realistic.
They show nothing to back them up, and 6 months ago when I checked all the plans that are now more expensive than my current one showed that I would save $100's of dollars a year! So unless I missed out on some killer deal that is no longer available I don't trust them all that much.

Anyways all I can do is assume they are correct for now without spending hours on end trying to figure it all out. is determine that I can charge @ $.23 a kWh so that is in fact the cost of charging, plus roughly an additional $17 a moth to account for the difference in plans based on my current usage and info provided.

Also setting up a separate meter for the vehicle seems pointless as the rates are the same.

 

[SMAlset]

I think when gas prices spike again over $4 like they are expected to, you will be finding a lot of drivers of large SUVs faced with very expensive refueling bills once again. Bad thing is these very expensive vehicles will be hard to trade in if they were recently purchased if owners are over their head on them at trade in time. I know there were stories done in the SF Bay area about this last go round. But I would think rising gas prices will have more people thinking moving to EVs especially if they are on the cusp of looking for a new car.

Californians are about to get whacked with a large increase in gas tax (after many years without an increase), plus rising gas prices due to limited domestic supply, and then of course we have the "summer" blend switch over coming soon.

 

[insaneoctane]

Everything about your situation screams "GO SOLAR", or go "more" solar, so something doesn't quite add up...

Generally speaking, solar pays for itself. Period. If you consider solar in high tariff areas, solar pays for itself quickly. SDGE looks to be so greedy, that having solar seems like an absolute no-brainer. With an EV, that's even more true. SO, every indication is that you should have lots of solar and payback should be fast. Now, you've mentioned your $250 solar loan. I can't help but wonder if that's part of why this doesn't make any sense? How many kW is your current system that you are paying $250/month for? Also, what is/was your expected ROI for your current solar array?

 

[Dave EV]

I hope these current calculations on the site are realistic.

They matched up with my hand-calcs the last time I verified them, so I think they're good.

They show nothing to back them up, and 6 months ago when I checked all the plans that are now more expensive than my current one showed that I would save $100's of dollars a year!

Rates have changed a lot in the last 6 months with the change in TOU periods.

Also setting up a separate meter for the vehicle seems pointless as the rates are the same.

Only makes sense if almost all your house electricity usage is during peak hours and you don't go very far over the baseline usage.

Besides, going whole-house TOU gives you an excuse to look into buying a PowerWall to shift solar production into the evening peak hours.

 

[Glamisduner]

Everything about your situation screams "GO SOLAR", or go "more" solar, so something doesn't quite add up...

Generally speaking, solar pays for itself. Period. If you consider solar in high tariff areas, solar pays for itself quickly. SDGE looks to be so greedy, that having solar seems like an absolute no-brainer. With an EV, that's even more true. SO, every indication is that you should have lots of solar and payback should be fast. Now, you've mentioned your $250 solar loan. I can't help but wonder if that's part of why this doesn't make any sense? How many kW is your current system that you are paying $250/month for? Also, what is/was your expected ROI for your current solar array?

I have a 6-7 Kw system although I think it only produces 5.5 tops.

I was just mentioning that the $250 becase my $1200 a year looked cheap hah. As in to avoid the no big deal your hardly paying anything anyways. The $250 a month extra makes a difference but that's the only reason I mentioned it. I don't remember my ROI but really it depends how long I stay and how long the inverters and panels will last and the whole thing was theoretical based on future rate hikes etc. If I add more solar I have to abide by NEM2.0 rules which I don't think I am fond of (although I'm not sure).

What I'm not clear on is how my NEM plan will work if I switch to TOU. If it is the same then I guess it is not much difference. What sucks is that the peak hours are set in a way such that so that your solar will not cover them. IN other words, while you overproduce you get credit for power at a lower rate than when your not producing during peak hours.

With tiered plan I get credit in Kw hours, and use them as needed. With NEM2.0 and TOU you only get credit at the current rate. So you would be selling power back to SDG&E at say 24 cents a kWh, then they charge you 58 cents kWh while your not producing. It's win / win for them.

They matched up with my hand-calcs the last time I verified them, so I think they're good.


Rates have changed a lot in the last 6 months with the change in TOU periods.


Only makes sense if almost all your house electricity usage is during peak hours and you don't go very far over the baseline usage.

So I might have been better off switching 6 months ago? I ebeleive I would be grandfathered in to Peak hours being 11am-6pm, but at least I'm producing solar durring these hours (was that better than 4-9?) ? My thoughts are they wanted everyone to switch to TOU so they can jack up the rates and that appears to be what happened. However we also just had our first full year with AC and I had checked rates before AC was really being used, so that could be some of it too.


Also I'm not sure where the 5 year thing comes into play?

"Utility customers who installed solar under the original net metering policy will be “grandfathered” in for 20 years from their original enrollment date. After that point, they will also move to NEM 2.0."

 

[liuping]

I am currently hitting Tier 2 power and my bill this month is going to be about $170 + $250 for my solar loan and I don't even have an electric car yet. I'm really having to take a closer look at what a model 3 will cost me and it's not looking good at all at the moment. In the winter my solar does not make nearly as much power as the summer, but in the summer I also have to pay for air conditioning and have higher energy costs (.47 cents per kWh instead of .40 is what it would be to charge the tesla).

TOU-EV2 is most likely the right rate for you given solar and an EV. AC can run all day until 4pm at the offpeak rate now, so it should help keep your peak usage down to a reasonable level.

During summer or winter charging you Tesla after midnight is roughly $0.228 per kWh.

Adding a Powerwall to eliminate peak usage all together is also an option.

 

[Daniel in SD]

I think that the main difference between NEM 1.0 and NEM 2.0 is that NEM 2.0 customers are forced to have a TOU plan after 5 years. It's all ridiculously confusing though. I have an 8kw Sunpower systems and supposedly it has a 25 year parts and labor warranty.
You're correct about producing at $.23 and buying at $.54. You can optimize a bit by running the AC full blast from 3-4pm and doing laundry, running the dishwasher after 9pm. The higher rate is only for 5 months of the year so it's probably not that bad.

 

[insaneoctane]

I have a 6-7 Kw system although I think it only produces 5.5 tops.

I was just mentioning that the $250 becase my $1200 a year looked cheap hah. As in to avoid the no big deal your hardly paying anything anyways. The $250 a month extra makes a difference but that's the only reason I mentioned it. I don't remember my ROI but really it depends how long I stay and how long the inverters and panels will last and the whole thing was theoretical based on future rate hikes etc. If I add more solar I have to abide by NEM2.0 rules which I don't think I am fond of (although I'm not sure).

What I'm not clear on is how my NEM plan will work if I switch to TOU. If it is the same then I guess it is not much difference. What sucks is that the peak hours are set in a way such that so that your solar will not cover them. IN other words, while you overproduce you get credit for power at a lower rate than when your not producing during peak hours.

With tiered plan I get credit in Kw hours, and use them as needed. With NEM2.0 and TOU you only get credit at the current rate. So you would be selling power back to SDG&E at say 24 cents a kWh, then they charge you 58 cents kWh while your not producing. It's win / win for them.



So I might have been better off switching 6 months ago? I ebeleive I would be grandfathered in to Peak hours being 11am-6pm, but at least I'm producing solar durring these hours (was that better than 4-9?) ? But I think they automatically just adjust them anyways? My thoughts are they wanted everyone to switch to TOU so they can jack up the rates and that appears to be what happened. However we also just had our first full year with AC and I had checked rates before AC was really being used, so that could be some of it too.

Your rates dictate everything, but I can tell you when I first installed solar I was also on a tiered plan. It only took me a few months before I did the calculations and compared to TOU which was a HUGE advantage for me. I can't do the calculations for you, but I can spell out the process I used:

1. Download the HOURLY data for your last 12 months (I had installed a TED energy monitor device, so I didn't need to rely on my power company to provide this, but I think they do now)
2. Use online software (PVWatts I think?) to estimate your hourly PV production. You may have actual hourly data which would be better (I didn't have hourly PV data yet when I did mine)
3. Excel that sh!t. I ran a 12 month, by the hour spreadsheet that compared TIERED rates vs TOU rates (yes, I row for each hour, so 8,760 rows minimum). This allows you to compare, by the hour, what get exported vs imported and rates

I did this to compare several TOU plans available to me and let me tell you, I went from hitting tier-2 with solar to having $500 credit at the end of my true-up period. So, my rates allow me to SERIOUSLY leverage TOU with my use profile. You just won't know your situation until you do your own comparison. DO NOT TRUST SDGE TOOL, they don't know how much solar you make, only how much you export. I suspect your high off-peak rates mean you won't find a way to get rich here, but I'd definitely do the analysis!

 

[McRat]

Read the specs on your inverter. On many inverters you can increase the number of panels to about 120% of the rated AC max output. ie - If you are 10kW, you can run 12kW of panels to it.
If the orientation or shadowing never reaches full rated power, you can also add some for that as well. Check with the mfr first.
But if your Permission To Operate is based on 10kW AC, there is really no great need to refile to bring the system to its full rated power that was planned out. It's basically tuning the system.

 

[Glamisduner]

They matched up with my hand-calcs the last time I verified them, so I think they're good.


Rates have changed a lot in the last 6 months with the change in TOU periods.


Only makes sense if almost all your house electricity usage is during peak hours and you don't go very far over the baseline usage.

Your rates dictate everything, but I can tell you when I first installed solar I was also on a tiered plan. It only took me a few months before I did the calculations and compared to TOU which was a HUGE advantage for me. I can't do the calculations for you, but I can spell out the process I used:

1. Download the HOURLY data for your last 12 months (I had installed a TED energy monitor device, so I didn't need to rely on my power company to provide this, but I think they do now)
2. Use online software (PVWatts I think?) to estimate your hourly PV production. You may have actual hourly data which would be better (I didn't have hourly PV data yet when I did mine)
3. Excel that sh!t. I ran a 12 month, by the hour spreadsheet that compared TIERED rates vs TOU rates (yes, I row for each hour, so 8,760 rows minimum). This allows you to compare, by the hour, what get exported vs imported and rates

I did this to compare several TOU plans available to me and let me tell you, I went from hitting tier-2 with solar to having $500 credit at the end of my true-up period. So, my rates allow me to SERIOUSLY leverage TOU with my use profile. You just won't know your situation until you do your own comparison. DO NOT TRUST SDGE TOOL, they don't know how much solar you make, only how much you export. I suspect your high off-peak rates mean you won't find a way to get rich here, but I'd definitely do the analysis!

I thought I was the only person confused! I was pretty lost when I got the letter in the mail.

I commend you for the time you spent figuring it all out! I was super busy when they announced it getting married etc so I didn't have the time or even understand how to calculate all those things. Actually I still don't as I don't have an easy way to find out what I have produced historically. I always wanted to get on of those devices that plug into the network, but I had 2 different inverters. One has bleutooth only and one is Ethernet. I wanted the Ethernet one for both inverters but I could never figure out the parts to order to switch it over so nother ever came of getting a monitoring device (I still don't know which parts to order to do this and I'm an IT and networking kinda guy). I asked on several forums and no one would tell me just to "call my solar installer" which I did do, but he never got back to me maybe calling him like 10 times and they are now no longer in business. Nothing but frustrations with the whole solar thing, my worst experience with contractors ever!

I'll have to look into PVWATTS when I have time to spend figuring out the schematics for my solar (Contracts never gave me the final copy so I may end up going up on the roof to estimate).

Read the specs on your inverter. On many inverters you can increase the number of panels to about 120% of the rated AC max output. ie - If you are 10kW, you can run 12kW of panels to it.
If the orientation or shadowing never reaches full rated power, you can also add some for that as well. Check with the mfr first.
But if your Permission To Operate is based on 10kW AC, there is really no great need to refile to bring the system to its full rated power that was planned out. It's basically tuning the system.

I'm guessing SDGE could tell me this permission to operate? I don't really know what it is.

 

[Sandiegodoug]

Sdge said I could increase system by 10%
And stay in nem 1. Also said I can get a 200.
bill credit per ev. Plan to add 4 south facing panels. They told me not to change to tou

 

[McRat]

...
I'm guessing SDGE could tell me this permission to operate? I don't really know what it is.

Among your documents related to the solar, is one called a PTO - Permission to Operate. This is issued after the building inspector (called the AHJ, authority having jurisdiction) has signed off the final inspection, and the utility has approved all submitted docs. Technically, you are not allowed to turn on the system except for test purposes until you are issued this PTO. It is the date your Net Energy Metering (NEM) takes effect. If you turn on your solar power before the PTO is issued, any surplus power you produce is wasted, it reads 0 kWh any time your production exceeds your electrical usage. Not that I would know...

The PTO gives you permission to operate at a noted kW number. I read that to mean as long as I do not increase the AC Inverter size, I can fine tune the DC side as I see fit as long as it complies with the building code. Panel in the shade? Relocate. Panels aren't producing as estimated? Increase DC rated size.

Before adding panels, you look at what your existing panels are doing:



The irregular shape due to air conditioners and skylights and shadows. You can see that adding panels to the right side is going give me the best bang for the buck.

 

[Glamisduner]

Read the specs on your inverter. On many inverters you can increase the number of panels to about 120% of the rated AC max output. ie - If you are 10kW, you can run 12kW of panels to it.
If the orientation or shadowing never reaches full rated power, you can also add some for that as well. Check with the mfr first.
But if your Permission To Operate is based on 10kW AC, there is really no great need to refile to bring the system to its full rated power that was planned out. It's basically tuning the system.

Among your documents related to the solar, is one called a PTO - Permission to Operate. This is issued after the building inspector (called the AHJ, authority having jurisdiction) has signed off the final inspection, and the utility has approved all submitted docs. Technically, you are not allowed to turn on the system except for test purposes until you are issued this PTO. It is the date your Net Energy Metering (NEM) takes effect. If you turn on your solar power before the PTO is issued, any surplus power you produce is wasted, it reads 0 kWh any time your production exceeds your electrical usage. Not that I would know...

The PTO gives you permission to operate at a noted kW number. I read that to mean as long as I do not increase the AC Inverter size, I can fine tune the DC side as I see fit as long as it complies with the building code. Panel in the shade? Relocate. Panels aren't producing as estimated? Increase DC rated size.

Before adding panels, you look at what your existing panels are doing:

View attachment 277750

The irregular shape due to air conditioners and skylights and shadows. You can see that adding panels to the right side is going give me the best bang for the buck.

Yea PTO I get it, I just don't know what was written we are allowed to operate at in the document. I had allot of problems trying to get the documentation from the installers because they took it with them once we had PTO, and it was weeks before they came back to give me the docs (I think they lost some of them). There's some more space on the roof to add panels but it might be diminishing returns due to shading from trees.

 

[insaneoctane]

@Glamisduner , sorry to ask such a basic question....Have you already made your house as energy efficient as it can be? How many kWh do you consume on an average day (don't count solar production)?