So what does it cost you per "fill up"

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foxwiz

Member
Joined
Jun 17, 2013
Messages
24
Location
Agoura Hills, CA
I was trying to figure out what a full charge would be on my vehicle. I am Southern California Edison territory and the tiers are different. Tier 1 is .13 per kWh, Tier 2 is .16 per kWh, Tier 3 is .27 per kWh, and Tier 4 is .31 per kWh. So I guess it depends on how much electricity you use during the day. I have people home during the day so laundry gets done, air-conditioning is used so I am guessing that I fall in Tier 3 or Tier 4.

The commute for my vehicle is between 40 and 50 miles per day which would use maybe 20 kWh. At 31 cents per kWh, that would be $6.2 per day.

My car gets about 17 MPG and driving 50 miles a day with gas being $4.29 for premium, I would use just under 3 gallons, say $12.66 per day. So my savings would be half. Not as great as I would have thought.

SCE has a plan to add a dedicated meter at the house for charging during the evening between 9 PM and 10 AM for .11 per kWh, but that would take an electrician to install a new panel on the side of the house. I could be coughing up $1k - $2k for an electrician. Ouch.

What are your savings?
 
I just looked at the SCE rates and one thing stands out to me regarding their "Home & Electric Vehicle Plan (TOU-D-TEV)" - the Peak time is 10am-6pm M-F and there are only two tiers, above and below 130% of baseline. Tier 2 Summer Peak usage is billed at 47 cents/kWh. That will really jack up your bill even though your EV charging at "Super Off Peak" is only 9 cents. If you have had a SmartMeter for a full year, SCE should be able to tell you which rate plan will give you the lowest bill. I would try to get them to give me an annual estimate with and without a dedicated meter to see how long it will take to pay off your electrician's bill.

For comparison, see the thread Understanding PG&E E9A Electric Vehicle Electric Rates.

Anybody in SCE territory with an EV should get a small solar PV system. Their rate plan is VERY conducive to solar. Think about it this way - solar will generate more than 80% of its energy in their peak time of 10am to 6pm. This is a quick and dirty calculation assuming you can always charge between midnight and 6am.
EV usage: 50 miles/day @ 3mi/kWh = 16.67kWh/day @ $0.09/kWh = $1.50/day
PV Peak Gen Required: $1.50/day @ $0.47/kWh = 3.2kWh/day *7/5 = 4.48kWh/weekday during 10-6 period.
PV DC Size Required: 4.48kWh @ 5.75h DC rating/AC kWh X 80% = 0.97kW DC Watt rating.

So, for Summer Season in SCE territory, you only need 1kW DC PV solar system to earn enough savings on your bill to pay for your EV driving. This is a tiny system - only 4 panels. Winter is not so exaggerated because the peak rate is less, the EV overnight rate is slightly more, and the solar generates less AC kWh per DC Watt, so if you only want to offset your EV, probably 2.5kW is enough throughout the year.

Now that I think about it, this analysis is exaggerated because it assumes that you are already on this rate plan, when in fact your are on a non-time of use plan. In any case, the hours that SCE uses for their whole home plus EV rate is much more conducive to solar than PG&E because we only get to count 2pm-9pm generation as peak. My solar is below 50% power at 4:30pm and dropping fast.

Long story short, TOU rate comparisons are not easy without real data from your house. My spreadsheet linked in the PG&E E-9 thread can be easily adapted to the SCE rate schedules. The tables for TOU hours and tiered rates just need to be adjusted - no logic changes should be required based on my quick perusal of the SCE rates.
 
After a couple of weeks, I have decided to get a second panel from SCE and I have gotten some quotes from electricians that put the install cost under $1,000 so I think that this will be a go. We will charge at night and if the occasional day charge happens then we just pay more for electricity.

Can you elaborate on the solar system that you purchased? Why did you go that route, and do you generate enough electricity to have the excess purchased by the utility? I will look into solar but maybe I could get a system that would handle all the household needs. We have a two story with two separate air conditioners. Our electric bills are high.
 
foxwiz said:
...

Can you elaborate on the solar system that you purchased? Why did you go that route, and do you generate enough electricity to have the excess purchased by the utility? I will look into solar but maybe I could get a system that would handle all the household needs. We have a two story with two separate air conditioners. Our electric bills are high.

These days are are myriad of options on solar but based on your description of your electric bills a solar PV system would be a no brainer for you. You can be saving money from day 1. You don't need any cash up front either (although if you have some that is just earning meager interest then you might want to put it into solar).

The basic principle is this, solar is cheaper than most of the electricity that you can buy today. If you finance the system then you simply trade your utility bill with a payment to your financier. The payments should end up cheaper than your electric bill. Most of the PV companies these days can you satellite pictures of your house to come up with a proposal without having to visit your house ahead of time. If your usage allows you to use time of use (TOU) then you can potentially save even more.

You don't want to generate more electricity that you consume, the amount of money that utilities pay for it makes it not worth it financially. The only reason to do is it you want to have the satisfaction of generating more than you consume. That's perfectly fine as long as you know that going in.

For some background. I have 13.5 kW of PV supporting to EVs. I've been driving electric cars for over 10 years. Our house uses an air source heat pump (w/ natural gas backup) for heat (and the last few days for cooling). We also have pool (which most people don't realize are big energy hogs). The PV was installed in two phases, the most recent one was installed by Solar City. If you want to use a referral here is my link: http://share.solarcity.com/a/clk/1hx7hC

arnold
 
foxwiz said:
After a couple of weeks, I have decided to get a second panel from SCE and I have gotten some quotes from electricians that put the install cost under $1,000 so I think that this will be a go. We will charge at night and if the occasional day charge happens then we just pay more for electricity.

Can you elaborate on the solar system that you purchased? Why did you go that route, and do you generate enough electricity to have the excess purchased by the utility? I will look into solar but maybe I could get a system that would handle all the household needs. We have a two story with two separate air conditioners. Our electric bills are high.
The important thing to understand about residential solar installations in PG&E and SCE areas is that they are based on Net Metering with an Annual True-Up. This means that your solar system is saving you money at full retail price by deducting the kWh generated from your kWh used. In some other areas, you have a separate meter on the generation (solar) and the utility pays you a different rate for your generation than they charge you for your usage. What, when and how they pay you is based on a Feed-In Tariff. Anyway, for PG&E and SCE with the Annual True-Up, you don't pay for any of the energy you use until the end of a full year from your interconnection date. The idea is that your bill should be negative in the summer and positive in the winter and you pay the final net amount. Remember, just because your energy charge for a given month is $0 or negative doesn't mean that you generated more than you used, especially with an EV. See my example here for what my house, with solar, would be on SCE EV TOU whole house rate.

PG&E E-9A & SCE TOU-D-TEV Rate Comparison

You will see there that I had a net usage of 310kWh and if I was in SCE territory my solar would earn me a Peak time credit of -$77.25, Off Peak cost $34.19, and Super Off Peak cost (mostly EV charging) $34.19 for a total net energy charge of -$18.28. My total generation for that period was 720kWh, so the energy charge for my total usage of 1030kWh on SCE Residential Rate D (4-Tier Residential Plan) would have been about $242. Putting my total PV system on my Home Equity Line at 4.5% APR costs me less than $125/month (10 year fully amortized). So, you can see that this is a no-brainer to avoid $200-$300 electric bills.

So, I highly recommend PV solar and don't get the extra meter for EV charging. Use the $1,000 for a deposit to get a solar system going.
 
PG&E E-9A & SCE TOU-D-TEV Rate Comparison

You will see there that I had a net usage of 310kWh and if I was in SCE territory my solar would earn me a Peak time credit of -$77.25, Off Peak cost $34.19, and Super Off Peak cost (mostly EV charging) $34.19 for a total net energy charge of -$18.28. My total generation for that period was 720kWh, so the energy charge for my total usage of 1030kWh on SCE Residential Rate D (4-Tier Residential Plan) would have been about $242. Putting my total PV system on my Home Equity Line at 4.5% APR costs me less than $125/month (10 year fully amortized). So, you can see that this is a no-brainer to avoid $200-$300 electric bills.

So, I highly recommend PV solar and don't get the extra meter for EV charging. Use the $1,000 for a deposit to get a solar system going.[/quote]

It looks like going solar could be the way to go. One problem I am still questioning, we may be in our house for a maximum of 10 years so I need to figure out if paying for the system within that time works. I do have a Home Equity line, but we did our kitchen two years ago so I don't have that to use. More investigation is needed. Thanks for the reply.
 
foxwiz said:
miimura said:
PG&E E-9A & SCE TOU-D-TEV Rate Comparison

You will see there that I had a net usage of 310kWh and if I was in SCE territory my solar would earn me a Peak time credit of -$77.25, Off Peak cost $34.19, and Super Off Peak cost (mostly EV charging) $34.19 for a total net energy charge of -$18.28. My total generation for that period was 720kWh, so the energy charge for my total usage of 1030kWh on SCE Residential Rate D (4-Tier Residential Plan) would have been about $242. Putting my total PV system on my Home Equity Line at 4.5% APR costs me less than $125/month (10 year fully amortized). So, you can see that this is a no-brainer to avoid $200-$300 electric bills.

So, I highly recommend PV solar and don't get the extra meter for EV charging. Use the $1,000 for a deposit to get a solar system going.
It looks like going solar could be the way to go. One problem I am still questioning, we may be in our house for a maximum of 10 years so I need to figure out if paying for the system within that time works. I do have a Home Equity line, but we did our kitchen two years ago so I don't have that to use. More investigation is needed. Thanks for the reply.
If you have equity, you could ask for a credit line increase from the same lender. Alternatively, you could re-fi just the equity line with a different lender. Obviously I don't know your financial situation, so I have no way of knowing if that would be advisable for you.
In any case, your house should be worth more with solar when you go to sell it. However, I don't have any hard data that shows that normal home buyers understand solar and are willing to pay more for the house than they would without solar. If you have any friends that are real estate agents, I would pick their brain to see if they feel that there is a real increase in selling prices with existing solar. This is probably hard to quantify and people who have installed solar are less likely to sell.

One more thing. I just realized that I quoted a bill of $242 without solar but I used the Residential Rate D when I should have used the same TOU-D-TEV rate plan because the usage did include EV off-peak charging. However, I don't have TOU data for just the generation portion, so I cannot make an accurate estimate of the energy charges in that condition. So, you know, grain of salt.... This info is worth what you paid for it. ;)
 
foxwiz said:
One problem I am still questioning, we may be in our house for a maximum of 10 years so I need to figure out if paying for the system within that time works.
Don't forget that adding solar increases the value of your house and makes it easier to sell. If you are not done paying off the loan by the time you sell, you will get your money back anyway. :)
 
Important Update. As of January 2015, many EV owners are receiving letters from Southern California Edison informing us that the utility is cancelling the TOU-D-TEV rate plan. Their proposed alternatives will undermine the effectiveness of solar systems purchased by EV drivers. Why EV Owners with Solar Systems are having their investments compromised so soon and before we can recoup our investment is baffling. What is going on at the CPUC and the State of CA to allow this to happy? Please visit http://www.protectourrates.com to become educated and to let our State representatives know about this issue!
 
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