My net cost (HELOC payments / total annual kWh production) came to $0.158/kWh. I have PG&E, so this represents a significant savings from year 1. You, not so much.
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Merrill
Merrill
I also have PG&E and have 4.1kw solar array, the most I could fit based on my roof and exposure. I have E-7 TOU on the solar and it works very well for me given that I get credit in the summer due to the expensive per kw charge from 12 to 6. I went with a second meter for the EV and with E9b rate of 5.5 cent off peak 12midnight to 7am. I have had my car for 1 year and 10200 miles and my cost to charge was $150. I did 5 superchargers during that time. My ICE car would have been around $2200.
This is the first I have heard of any kind of subsidy. I didn't even get to the point where we talked about cost for trenching, the PG&E guy just said "it's significant" and I moved on based on that. I'm sure they were under no real incentive to tell me "oh by the way we'll eat part of that" - so I'm actually going to go back. An electrician friend will do the actual wiring for me at cost (with all appropriate permits etc) so that's no big deal, IF we get the right amount of power up to the house. What you describe with a single panel with two meter sockets is exactly what I was considering. PG&E charges (I think) $100 for another meter but am not sure.
I agree with the comment about smart meter technology being able to do this without all the hoop-la. These days there is no reason why we can't have some kind of setup like this with a sub-metered breaker or something like that.
I am going to download your model. I created my own, but I am only a mid-level modeler and am under no delusion that my Excel-fu is perfect. The one bug in the ointment is that we went solar in September 2013, so last summer's usage does not have any solar gen in it. When I modeled I used some assumptions.
I think I paid about $3,500 for utility trenching for about 40 feet. This included preparation for gas and electric, but may have also included the separate parallel trench for water. In addition, PG&E charged me about $2,500 for the new service including the cost of the conductors from the pole to the meter. This may have included the construction temp power install and removal and gas pipe install as well. I don't recall exactly. Remember, mine was all new construction, not upgrade.
There is another rate change effective 5/1/2014 that I haven't entered in the spreadsheet. E-9A Summer Peak is up to $0.57678/kWh starting at 200% of baseline. Schedule EV also had a change on 5/1/2014, but the Winter rates all went down while Summer Off-Peak went down and Part-Peak and Peak went up.
Guys, I just got my first full month's Socal Edison bill since getting the Tesla and it is BRUTAL. Usually my bill is ~ $30/mo. For May, it was $195! I've been going over the numbers and different plan options, but it looks like the plan I'm already at (regular residential -- Schedule D) is the cheapest. Does anyone want to double-check my math for me?
Rate options:
Electric Vehicle Rates | Rates | Your Home | Home - SCE
My usage (rounding high for worse-case scenario):
10am-6pm: 3.5 kwH (This is the highest I've gone -- with the A/C on when it's 101F out)
6pm-12am: 0.7 kwH
12am-6am: 0.7 - 5.4 kwH (I charge the Tesla every 3rd day which is where it reaches 5.4 kwH)
I knew that I would be paying more for for electricity, but currently, the cost of driving the Tesla vs my old hybrid Prius is surprising me. I think what's really costing is that I'm popping into Tier 4, but not sure how I can get the usage down. We already have HE appliances, most of our lights are LEDs, etc. Not running the A/C during hot days isn't an option since I work from home and there's also an infant at home.
Rate options:
Electric Vehicle Rates | Rates | Your Home | Home - SCE
My usage (rounding high for worse-case scenario):
10am-6pm: 3.5 kwH (This is the highest I've gone -- with the A/C on when it's 101F out)
6pm-12am: 0.7 kwH
12am-6am: 0.7 - 5.4 kwH (I charge the Tesla every 3rd day which is where it reaches 5.4 kwH)
I knew that I would be paying more for for electricity, but currently, the cost of driving the Tesla vs my old hybrid Prius is surprising me. I think what's really costing is that I'm popping into Tier 4, but not sure how I can get the usage down. We already have HE appliances, most of our lights are LEDs, etc. Not running the A/C during hot days isn't an option since I work from home and there's also an infant at home.
$165/month extra for charging is definitely a LOT! On the other hand, I do not understand your break-down numbers. If you only spend 5.4 kwH to charge up the Tesla, that does not fill it up, even if you mean 3x that amount (split to the 3 days), it still only covers a small portion of the battery capacity of 85kwh.
On the site you linked, I see Regular residential (Schedule D) listing 31c/kwh, while "The Home & Electric Vehicle Plan" lists only 10c/kwh for midnight to 6am range, so you should definitely get that plan. At 10c/kwh your full Tesla charge would be about $9 for evey 3 days, so for a full month about $90 in worst case (if you use up all charge every 3 days).
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stopcrazypp
Well-Known Member
Do you mind telling what your baseline allocation is (in kWh, specify Summer or Winter) or ideally your baseline region number (5,6,8,9,10,13,14,15, or 16)? It'll be helpful (can simply just make a spreadsheet to calculate the cost of all the options).
You can find it here under the "Baseline Allocation Chart and Baseline Region Map" section by looking up your location in the map or by region.
https://www.sce.com/wps/portal/home/residential/rates/residential-plan/
And I'm assuming you don't want to install a second meter for the EV only (or is it also an option)?
And as a basic check on math, you said the peak at night is 5.4kWh every 3 days, but that seems extremely low. That only adds up to ~54kWh per month for the EV, which is only good for about 140 miles of travel.
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Sorry, bad phrasing. The 5.4kwH is per hour. It looks like the Tesla uses that from 1am-5am, so 5.4 * 4(hours) = 21.6kw
Yeah I was playing around with numbers for the Home & EV plan, which is great for the 10c/kwh off peak rate, but the on-peak rates for regular usage during the date is 28c, so a big jump than what I was already paying. Since I can't decrease my day usage any more than I have, the numbers don't make it any cheaper.
I'm in region 9, so baseline numbers:
basic: 13.3(summer) 10.8(winter)
all electric: 12.3(summer) 15.4(winter)
I'm really surprised at people who say charging the Tesla only added $30 to their monthly bill. I don't think I drive that much considering I have a 0 mile commute.
If you are using 21.6kW a day, that about 60 miles a day driving. that a lot for someone with a 0 mile commute.
Solar is definitely the way to go. Get a system at least large enough to keep you down in the lower tiers or, if you switch to Time of Use rates, to cover the Peak rates times. Then you pay only the lower rates for charging your car.
Yes but that's 21.6kW per 3 days (I only charge it every 3rd day) so the 60 miles of driving is for 3 days. Mostly it's running errands, going to lunch, etc. I don't want to consider solar since the payoff (including upfront costs) won't be until 10-15 years after, no? Also, the way the roof of my house is pitched, its style, and where the sun hits -- solar panels would look so ugly on it, which is a silly but major concern for me.
I was lucky, the south faces roof area on our house faces away from the street.
I have a different way of looking at payoff costs. Since we saved money the from day we switched it on, I consider it as having a 0 year payoff time. There are no up front costs after federal taxes credits, and the money we were paying to SDG&E was more than the cost of the loan + interest. The electricity rates when up quite a bit last year, so we'll save even more this year.
San Diego is nearly perfect for solar (crazy high electric rates, combined with mild weather and lots of sun). I don't know what it's like where you live.
jcaspar
Member
I want solar but cannot seem to get it to work financially. We use about 14,448 kWh per year. Base price is .09 per kWh for first 700 kWh, 0.18 after that. EV rate is .06 so car is cheap. Average monthly bill is 151$ before the car, about 16$ more with the car (about 1000 miles per month). Assuming a 5% increase in electricity cost per year and the cost of the system it seems it would take 15 years to break even, assuming I would have made nothing on the install cost otherwise. Maybe panels are just too expensive yet for my electricity cost? System was quoted at about 35,000$ after rebates.
I agree. It's much harder to justify at those rates.
Here in San Diego our rates are much higher. On tier rates, the lowest tier (the first 336kWh), is $0.15, but tier 4 (everything after 672kWh) is $0.37. In order to get the "cheap" EV rate of $0.16 super off peak (12-5am), you have to sign up for time of Use rates, which has at $0.44/kWh rate during the day.
What do realtors say about residual value of the equipment after x years that can be captured in the home's appraisal/price? Seems to be often overlooked in these calculations. At some stage, and perhaps already in parts of California, some kind of "green" equipment will come to be expected by home purchasers.
That's the problem. With the rate I'm currently at (residential), there is no "cheapest period." Usage during any time of day is the same rate. When I exceed a certain amount of kwh, I get bumped up to the next tier, which is more expensive. Without the car charging, I usually stay at tier 1 (cheapest). With car charging, I end up going to tier 4. The tiers are calculated as total usage each month, so it's not like I can back off on certain days or hours.
Call Edison and see if they will recalculate your last bill on the Home & EV Plan so you can compare. If they can't/won't do it, see if you can download your SmartMeter data. From that, I have a spreadsheet that can bin the time periods and calculate the energy charges from the tiers. I don't have the SCE rates in the spreadsheet because I'm in PG&E territory, but it's designed to be easy to modify.
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ChriZ
Member
You need to change to the Home & Electric Vehicle Plan (TOU-D-TEV) plan. This would give you the same pricing for super off peak even at 2 tier which is the max tier. I use a similar one for PGE which is similar to all you can eat during off hours plan. My bill has only gone up $40 a month from $60 to $100 average now.
