rookie questions - new owner in Los Angeles

nishy1 said:

Guys,
I'm a bit (very!) confused about the charging installation process. Can someone help educate a total luddite?

The FACTS - have a P90D being manufactured in Fremont - expect delivery in 7-10 days - car has a single charger. I typically drive from 20-100 miles per day and rarely do long road trips.

I am thinking of installing the regular NEMA 14-50 mobile connector as i'll never get the benefit of the HPWC and won't really need to buy another connector. Would welcome comments on that.

However, where i'm most confused is the process:

1) I spoke to my local electrician (who has a day job wiring high end homes but does this kind of thing on his own on the weekends) and an electrician recommended by Tesla. Apparently i need a 40/50amp double breaker for my fuse panel since there is no space. The 40amp will power my AC unit, the 50amp will be for the tesla. The tesla recommended electrician will charge about $1200. The local guy will charge $125 ph and thinks its 5 hours max.

2) I then spoke to LADWP, my local utility. They said i need to do a few things:

- file an EV service request form
- call the local rep to see if there are any service modifications required
- choose between a Time of Use (TOU) meter or a flat discounted rate
- get a permit from LADBS
- get an inspection so i can get the $750 rebate.


Am i missing anything? Any advice for me here? Does the cost make sense? Do you recommend the TOU meter?

thanks all...this stuff is so confusing to me. i'm just not a science guy!

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I used to be a science guy. Hands on, did my own construction, wiring, reading up on rules and learning new languages like kWh instead of gallons.

Since I don't live in LA, I cannot comment well on #2, but I will give my worthless opinion anyway.

You only need a 14-50 outlet. Go for the guy who does this in his spare time. Don't waste your money. He should know what he's doing and do a good job. They will likely charge you for a TOU meter, which may not pay for itself, but that's just a decision. Not critical.

Nothing wrong with filling up your circuit breaker box or using half size breakers, if the electrician friend thinks it's good. You will likely be doing timed charging at night, in order to get the better rate.

LADWP probably has good advice. You should get a discounted rate, and a TOU meter will charge you correctly, but the flat rate is a lot easier, while maybe being more in the power company's favor. As to not driving it much, well, good luck on that. I found that my miles went up quite a bit, over 80,000 miles in 3 years. Of course, trips are supplied by Tesla.

I don't know where you are getting a $750 rebate from. If that pays for the permit and the install, go for it.

In Monterey, so the utility is PG&E. But the scary stuff sounds similar. They said they have to check your meter, they got to see if the service can handle it, etc. When I explained I am using an existing circuit, my billing schedule changed and we got a nice letter saying all good. In my case the rate is "EV-A", it is not a separate metered panel. Rates are in the link below and are around 10 cents between 11:00 pm and 7:00 am, 22 cents until mid afternoon, and 42 cents from something like 2:00 to 9:00 pm. Use the car's charging timer, which is remembered by GPS, and it will take care of itself, as long as you plug it in when you park it. Tessie is scheduled for 11:30 pm post evening electrical activity. Set your amp's on the charger to no more than the lower of your circuit breaker, or 40 amps, which is the remote chargers limit. That too will be remembered by GPS location. Nice set once, and forget, http://www.pge.com/tariffs/tm2/pdf/ELEC_SCHEDS_EV.pdf

I use a 30 amp electric dryer circuit which I route to the garage. Tessie charges at about 21 miles per hour, with the remote charger that came with the car. Our monthly electric for Tessie is about $33, and about 75% of our electrical consumption. TOU is required to do the different rates by Time of Use. I did the electrical work myself. My driving is potentially lower than yours, commute is about 20 miles round trip. 2013 P85+

You need to understand clearly the rate structure(s) offered by the monolithic LADWP before you finalize your electrical installation. Do you want two meters (one for the house and one for your Tesla?) Do you want time-of-use for both or only the Tesla that can charge almost 200 miles from midnight to six AM? Do you really want time-of-use if you keep just the one meter? Do you have room in your existing panel, or do you have to have a larger or second panel? You don't say whether you live in the Palisades or in Northridge, so summer air conditioning use might or might not be significant.

We have PG&E, and we live in the Central Valley. We also have a modest 4,500-watt solar display. We could have signed up for the EV-A rate (referenced above) but that is strictly time-of-use, and we would get clobbered from June-September (it is 105 today) running our HVAC at 40+cents per kWh. We can opt for EV-B which is a separately-metered installation, and is time-of-use, but of course we charge in the wee hours at 10 cents.

Once you determine which situation fits your needs the best (and you might not have an option) then you can decide how to go about it.

For the record, we had an electrician who did moonlight work install the 14-50 plug. We had room on our 200A panel, so just put in a 50A breaker, and installed the wire and plug. We do not have an EV-rate, just the usual tiered structure with baseline, etc., and net electrical metering. This worked best for us.

Good question, but most of all, enjoy your new Tesla! You won't regret it!

nishy1 said:

The FACTS - have a P90D being manufactured in Fremont - expect delivery in 7-10 days - car has a single charger. I typically drive from 20-100 miles per day and rarely do long road trips.

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I realize this is more about the installation, but I just wanted to note that an old dryer outlet would be enough if you wanted to wait on dealing with this. I charge my P90D (single charger) on an old dryer outlet and get about 16mi/hr, which means it takes about 6.25hr to charge 100 miles.

I have PG&E E-6 SmartRate TOU, which starts at 9pm, and ends at 10am, which gives me more than enough time to charge. As a side note I recently did a test drive of range from 90% to 10% with range mode off, and it was 207.9mi. At 16mi/hr I can charge 208mi in the 13 hours I'm off peak. Anyway, regarding the plan and a separate meter. I thought about this and I'm waiting to see what my power looks like for a couple months before I decide. I've talked to a couple people that said their rates when down by switching to EV-A, but when I looked at it, based on my usage and patterns, it would cost me 20% more per year. That may change after having the car charging for an entire month, but it might also not be the best plan.

I just wanted to share this because it seems like there's a lot involved by your description and you might be able to give yourself some more time to figure things out.

Sounds a little too complicated. I live in OC and Edison is my electricity company. All I did was have an electrician come and install a 15-50 outlet. He took care of the permit with the city and it was all done in a day.
What could make it more complicated is if LAWP has an EV plan similar to Edison. They offer a lower rate to just charge your EV regardless of the time. But it requires a separate meter. That's expensive. So I chose a plan where electricity is cheaper at night but all through the same meter. That works perfectly fine as I only pay 10ct per kWh at night which is when I charge my car anyways. The separate meter only makes sense if you plan on charging a lot during the day.

nishy1 said:

Thanks man and thanks everyone. How many kW does it take to charge the car?

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Going from 21.23mi rated to 271.94mi rated, it added 77.72kWh. There's some loss, but I don't know how much so it's hard for me to say what the power required to add that many kWh was.

nishy1 said:

Thanks man and thanks everyone. How many kW does it take to charge the car?

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I think you may be mixing up kw and kwh. Don’t worry too much about it; lots of people do it often, but you should probably learn what they are and how to use them, because if you ask questions using the wrong term, you may not get the answer you’re looking for.
Kw (kilowatt) is a unit of power, which is a speed of energy delivery. A regular wall outlet is about 1kw. The 14-50 outlet for charging your Tesla is about 10kw.
Kwh (kilowatt hour) is a unit of an amount of energy. So that would be how much energy got put into your car’s battery or how much energy you buy from the electric company.

So as to your question, if you meant kw, the car can charge on many different kw levels—no particular one needed.

If you meant kwh, then it depends on how far you drove that day as to how much energy you need to put back in that night. For ballpark numbers, about 3 miles is close to 1kwh. So if you drove 60 miles, that would be about 20kwh that would be needed to refill. That would take about two hours on your 50A outlet.

nishy1 said:

Thanks man and thanks everyone. How many kW does it take to charge the car?

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Your P90D battery has about 85kWH of useful energy when fully charged. A few kWh are always maintained by the cars firmware to prevent damage to the battery and you cannot use it to drive the car.
If you drive it to the point where the range displayed is zero or very close to it (not recommended!) then you will have to put about 85kWh worth of electricity back into it during charging.

LADWP rebates are only valid if you install a stand-alone TOU meter (exclusive to an EV). There is a $250 rebate if you install the meter and circuit.

The up-to $750 rebate applies to a Tesla HPWC or similar EVSE equipment. You will not receive the $750 rebate if you install a NEMA 14-50 outlet.

This info and more can be found here:

https://www.ladwp.com/ladwp/faces/wcnav_externalId/r-sm-rp-ev?_adf.ctrl-state=9lr0pxqmw_4&_afrLoop=1094482468798234

Cheers,

nishy1 said:

I thought that the nema plug qualified as a category 2 charger.

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In the general sense of the term, you are correct that a 14-50 plug is level two because it charges at around 9.6kW on a 240-volt system. However, the LADWP clearly indicates on its fact sheet questions and answers that only J1772 plugs are eligible for the rebate.

The NEMA 14-50 plug is a common plug found in many RV parks and other places where campers go. I am guessing that they don't want a guest parking in your driveway with his RV and getting electricity at the cheaper rate. The J1772 can only be used by electric vehicles.

cpa said:

The NEMA 14-50 plug is a common plug found in many RV parks and other places where campers go.

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NEMA 14-50 is also used for stoves, ovens, cooktops and other appliances, so of course LADWP is not going to give a rebate for installing it, even though you are unlikely to plug in a stove or oven in your garage.

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rookie questions - new owner in Los Angeles

If you have a south or west facing roof, it would be well worth getting solar panels installed. I plan to install a 4.8 kW solar array when I order my Tesla and expect that it will provide about 7,000 kWh per year, enough free power to cover 12,000 miles per year of an S85 plus 90% of our household electricity use. We live near the coast and do not need AC, so you would need a larger array to cover your usage, but the idea is the same and the savings no doubt much greater since you would be in a higher rate tier than I am.

Although our $60 per month electric bills are not enough for a leased solar system to pay out, a purchased one (after 30% Federal tax credit if installed before end of 2016) for us figures out to a 13% return on investment - tax free! Where else can you get that kind of investment yield? And the bonus is that your carbon footprint will be zero, so whether you are concerned about reducing CO2 emissions or reducing your consumption of non-renewable resources, it is a win.

cpa said:

I am guessing that they don't want a guest parking in your driveway with his RV and getting electricity at the cheaper rate. The J1772 can only be used by electric vehicles.

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I have actually seen an adapter that plugs into an EV plug J1772 and has a 15-50 on the other end to power an RV.

nishy1 said:

So if I get the power wall the DWP basically pays for it?

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Power Wall or the HPWC? They're two different things. The $750 LADWP rebate will cover the current cost of the HPWC, not including the sales tax.

NOTE: To qualify for the EV rebate ($250 and/or $750), you will need the circuit and any outlet/EVSE installation inspected and approved by the LADBS. Any licensed electrician can coordinate this for you.

The second bullet item on your list from LADWP (seeing if any service modifications are needed) can be important if your house is older, or if your electric service is smaller than 200 amps...

I work for the local utility here and sometimes if this step is skipped, we end up seeing low voltage issues later (especially if other appliances are running when the car charging is taking place). Since you're going to be dealing with LADWP anyways, I would recommend not skipping that step and having them check on your service to make sure it is capable of handling the additional load...

nishy1 said:

Thanks guys

RandyS - just waiting for them
To call back. They're not exactly speedy. That said there are literally 5 tesla's on my block - and the houses were all built in 1998.

@txacoli - my bad i meant the hpwc. I think what I took from your message was that he regular umc cord into a nema outlet doesn't afford me a discount but paying the extra 750 for the hpwc will effectively be free because the DWP pays for it.

One thing - does anyone know if the tou meter costs a lot on a monthly basis? I read there is a service fee.

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Correct. There is no $750 LADWP rebate for a NEMA 14-50 install, but you should be able to get the $250 for the circuit and TOU meter installation.

I originally had a NEMA 14-50 installed when the HPWC was more expensive. When Tesla decreased the price of the HPWC to $750, I swapped out the 14-50 for the HPWC. The initial circuit for the 14-50 is on a 50 amp breaker, so I can only charge up to 40 amps on the HPWC. No worries, as I only have the single charger in my car.

Yes, there is normally a $8.00 LADWP monthly service fee for a TOU meter, but that fee is waived when the meter is exclusively dedicated to an EV.