I finally got on the phone with the LADWP EV department this week. They were very helpful. So helpful in fact that I could hardly get a word in edgewise, and I ended up forgetting to ask about the hard-install vs. outlet-install. Might call back about that.
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The current incentives:
1. Rebate is up to $750 for the cost of the EVSE (does not include labor for install, just the cost of the EVSE itself.) They say it takes 3-6 months to get the $750 rebate once the application is in. Any cost of installing a 240v line in the garage is out-of-pocket.
2. You can get a 2.5 cent/kWh discount on the base rate, and a one-time $250 credit on your bill, if you decide to install an additional main electrical panel with a time-of-use (TOU) meter that is just for the circuit on which the EV is charged. The cost of installing the entirely new, second main panel on your house or garage is out-of-pocket. (So the electricity from the grid comes to one new panel for just the 240V line in your garage, and one old panel that handles everything else for your house).
3. It is also possible to switch from a tiered rate plan (which I am currently on) to a TOU plan. Switching types of plan is free, and LADWP doesn't charge you to switch your existing meter to a TOU meter.
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Regarding #1:
I just had Roy from RG Electric out to give me an estimate on installing a 240V line. I do have a sub-panel in my garage, however the conductor (wire) connecting that sub-panel to the main panel on the house (where I connect to the grid) is only rated for 40 amps. Roy said he said he's been dinged before because when an inspector came to look over the install of an EVSE, the EVSE specs said it was rated for 30-40 amps (even though it was a "30 amp EVSE"), and the conductor coming to the sub-panel in the garage was only rated for 40 amps, so he had to re-do the job with 50 amp conductor because wiring has to be rated for 10 amps above what could possibly drawn. Since then, he always makes sure everything is rated for 50 amps, so there are no issues in having an EVSE that can draw 30-40 amps.
Since my sub-panel is connected to the main panel via only 40-amp-rated conductor, he's recommending just bringing new 50-amp conductor from the main panel on the back of the house all the way to the garage, not going through the garage sub-panel at all. He would use outdoor conduit along the roof (it's a slab house so can't route underneath). Probably a total length of about 80 ft total from main panel to EVSE.
If the cost estimate comes back at under $500, I might do it soon. If higher, then I probably won't do it for a while, as I don't REALLY need Level 2 charging at home with my current ability to Level 2 charge at work for free. Still, it'd be nice to have for added flexibility, and that $750 rebate won't be around forever.
UPDATE 5/15/2014: Estimate for the above came in at $2250. As such I will get a couple more estimates, but if the other estimates are similarly high I will just stick with Level 1 charging at home for the foreseeable future. Level 1 is currently meeting my needs, and it's not worth $2k+ for the added flexibility of Level 2 at home when I have Level 1 & 2 charging available for free at work.
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Regarding #2:
(installing the TOU meter and a second panel). Is it "worth it"? Probably not.
Pluses: If you take this option, you get a 2.5 cent/kWh discount off the base rate on that circuit (8pm - 10 am M-F, All day on weekends). The base rate for a TOU plan is 12.5 cents/kWh, so with the discount I'd pay 10 cents/kWh on nights and weekends. Plus the $250 one time credit on my LADWP bill.
Minuses: The install of the new main electrical panel is completely out-of-pocket. The LADWP guy said he's had customers tell him that installation cost is AT LEAST $1500, with $3000 and up being more typical. In addition, there is apparently an $8/month service fee from LADWP to have a second TOU meter.
Roy from RG Electric come gave me an estimate, and he said that he had done this for another customer for $3k. Both the LADWP guy and Roy told me they thought it wasn't worth the cost of the install just to get the 2.5 cent discount.
Question: How long before the savings from the 2.5 cent/kWh discount covers the cost of the TOU new panel install?
Answer:
At least 7.4 years, as much as 49.8 years, depending on assumptions. UPDATE 5/15/2014: Most likely range is at least 16.3 years, as much as 49.8 years, due to likely $3k cost of separate panel/TOU install. Conclusion: I will probably not opt to get the second main panel installed just to get the discount. There are other things I would do with the ~$3k install cost that would yield greater benefits. (ex: put it toward cost of solar panels, either for electricity or pool heating.)
My math:
For the shortest payback period, I assume:
-Cost of new panel and TOU install: $1500.
(UPDATE 5/15/2014: With a $2250 estimate for just installing a 240V line WITHOUT a new panel for TOU, I think $1500 is a gross underestimate for my situation. Only the analysis based on a $3000 install estimates likely to be close to accurate.)
-I use half of a full charge every day at home.
(My work commute is 44 miles roundtrip, and a roundtrip depletes about 43% of my battery).
So I'd charge 10.5 kWh every day. (21 kWh divided by 2) This is an overestimate, since in reality I charge mainly at work for free, and only need to charge at home on the weekends. The less I charge at home the less I'd be saving with the 2.5 cent/kWh discount, which would increase the payback period. But let's go with this overestimate assumption to get the minimum payback period for someone who has my same commute but is not lucky enough to be able to charge at work for free.)
How much electricity would I use to charge the car every month?
10.5 kWh per day x 30 days per month =
315 kWh/month
How much would it cost to charge the car every month?
Tier 1:
$44.10 per month. @ 14 cents/kWh
Tier 2:
$53.55 per month. @ 17 cents/kWh
TOU base: $31.50 per month @ 10 cents/kWh, + $8 per month separate TOU meter fee =
$39.50 per month.
How much would I be SAVING each month by getting the 2.5 cent/kWh discount?
Compared to Tier 1:
$4.60 per month
($44.10 - $39.50)
Compared to Tier 2:
$14.05 per month
($53.55 - $39.50)
So how long before that savings cancels out the $1500 I spent to install a new panel?
(($1500 cost of install - $250 bill credit) / $4.60 per month) = 272 months =
22.6 years
($1500 cost of install - $250 bill credit) / $14.05 per month) = 89 months =
7.4 years
So at LEAST 7.4 years. UPDATE 5/15/14: THIS IS LIKELY A GROSS UNDERESTIMATE GIVEN $1500 IS UNREALISTICALLY LOW INSTALL COST FOR A SEPARATE TOU METER PANEL IN MY SITUATION.
How long if the new panel cost $3000 to install? (MORE LIKELY)
(($3000 cost of install - $250 bill credit) / $4.60 per month) = 598 months =
49.8 years
(($3000 cost of install - $250 bill credit) / $14.05 per month) = 196 months =
16.3 years
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Regarding #3: (switching your entire house from Tiered to Time-of-Use (TOU)):
The LADWP guy does NOT recommend doing this for anyone in parts of L.A. where it gets hot during the summer (i.e.: everywhere except near the beach), since you'll be using your AC during peak hours, incurring a higher rate than you would if you stayed on Tiered as long as you can stay below Tier 3. Tiered is a better option than TOU for hot regions.
The
current residential electric rates for LADWP are:
Tiered plan (rounded to nearest cent):
1000 kWh at 14 cents/kWh
Tier 2: 17 cents/kWh
Tier 3: 21 cents/kWh
TOU plan:
Base rate (M-F 8pm - 10 am, Weekends all day): 12.5 cents/kWh
Low peak: 16 cents/kWh
High peak: 24 cents/kWh
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