Cheaper to charge at 240 than 120?

Discussion in 'Prime Plug-in Charging' started by stevepea, May 12, 2017.

  1. stevepea

    stevepea Senior Member

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    Sadly, I only have 120V at my house, not any 240V outlets (houses in this tract are early 1960s era). A neighbor has 240V in his garage, but looking at it, it was obviously installed after the house was built (but before he bought the house).

    A friend today thought it would be much cheaper charging if you have 240V than 120V, because you only need to charge for 2 hours instead of 5.5 hours. Is that right? It sounds strange, because even though it's faster, don't you need the same amount of energy to charge the battery, whether delivered at 120 or 240?

    So what I'm asking is... is it really cheaper (and by how much?) to charge at 240V than 120V? Or is my friend mistaken? If my price is 16c/kw, and 240V charges twice as fast as 120V, does that mean my 240V charges would only be 1/2 the cost as when charging at 120V? Doesn't seem right, but I don't know.

    Also, especially considering the small size of the battery (and that I don't drive that much -- maybe 7k-8k a year at most now) I probably would never make up the difference in the cost to install a 240V outlet in the garage, right? (which I've seen online could easily cost $2,000)...

    Not concerned about speed, just about cost. Is it cheaper charging the Prime at 240V than 120V, or about the same (just different timeframe?) Thanks!
     
  2. Lee Jay

    Lee Jay Senior Member

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    The difference is small. You'd never make up the cost of a charger and the cost of running 240V electrical service to your garage to run it.

    2 hours versus 5.5 hours is fooling your friend because he doesn't realize the faster one is spinning your meter two and a half times as fast while it's charging.

    Look at it this way. Which coats more, a gallon bucket filled by your hose at full blast or the same bucket filled by a trickle of water from the sink? Same bucket = same cost for the water no matter how fast or slow you fill it.
     
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  3. DavidA

    DavidA Prius owner since July 2009

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    It is all about turn around time. 2 hrs. vs. 5.5 might be important for some of us and it could allow two sets of EV-only errands on the same day while charging after the first run. For me it is about security. I'll be charging outside, 5 feet from the street that dozens of high schoolers frequently walk to and from each day. I don't want to baby sit the car any longer than necessary.
     
  4. HPrimeAdvanced

    HPrimeAdvanced Senior Member

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    Steve, 240V or 120V charging should cost the same; please see other post regarding this. The charger cost is much cheaper than what you quoted. I live in Anaheim and got charger for about $500 + $600 for certified electrician to install, including all his materials, tubing, and 240V outlet to my existing panel in my garage. He ran about 30 feet of tubing. That's not all! Anaheim gave me a check for $1000 as an incentive after the installation. I provided photos and invoices for the project. Net cost: $100 !!.
    I keep saying it, I love this car!
    If your city does not provide a similar incentive here in California, check the state incentive program for chargers.
    Good luck!


    .
     
  5. Prodigyplace

    Prodigyplace Senior Member

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    They thought you installed a public charging station? :LOL:
     
  6. David Beale

    David Beale Senior Member

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    Hey, he's a member of the public. ;)
     
  7. HPrimeAdvanced

    HPrimeAdvanced Senior Member

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    No sir, seriously, the incentive is to promote private charger installations to encourage people to use EV and PHEV cars in our area. I had to furnish photos, remember, of my charger INSIDE my private garage. The charger has to be a Level 2, 240V unit. Yup, I LOVE this car!

    .
     
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  8. priuscatprimeguy

    priuscatprimeguy Senior Member

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    Ok, time to move your car out, I'm coming over to charge my car:D
     
  9. Prodigyplace

    Prodigyplace Senior Member

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    You must be desperate, driving from Michigan to California for a charge. Who said the Prime was green? :LOL:
     
  10. fotomoto

    fotomoto Senior Member

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    "Based on the data analyzed in this study and the expected conditions of residential charge events, Level 2 charging would likely yield approximately 2.1% efficiency gains. Under the assumptions used in Figures 2 and 3, this would amount to an estimated 119 kWh energy savings annually and 928 kWh energy savings over the lifetime of a vehicle. At minimum the cost of a Level 2 EVSE retrofit and installation would be over $500 and the total value of kWh savings at current prevailing energy prices in Vermont would be around $150. "

    https://www.veic.org/docs/Transportation/20130320-EVT-NRA-Final-Report.pdf

    Add in the additional savings from the federal tax credit (still available?) and any state/local incentives for purchasing/installing a home charger and the fuel savings from more EV driving via quicker charges and, yes, the level II EVSE might pay for itself over its lifetime. :whistle:
     
  11. HPrimeAdvanced

    HPrimeAdvanced Senior Member

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    You are all cordially invited to share lunch, for ourselves and our Primes at my house; just give me a yell when you're comin' by, Har, har
    If you want a party, I'll arrange to play with my band, A Choired Taste!
    Come on down, kids
    I would love to see my neighbors' faces when a bunch of Primes show up, although I do live on a cul de sac, and it might get a bit crowded! It would be fun to meet all you heretofore "anonymous" folks!

    .
     
  12. stevepea

    stevepea Senior Member

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    Thanks, folks. That's what I figured. No worries, just wanted to make sure.
    HPAdv, thanks for the invite! One of these days, might take you up on it and drop by!
    I did quickly look into incentives, but nothing available. Seems the only two cities that have/had incentives were Anaheim and Burbank (lucky you live in Anaheim!) And Calif now will only let you "borrow" the funds (not give), which you pay back by them attaching extra $ to your yearly property tax bill.

    Edit: looks like the AQMD does have a small incentive: $250 (+250 more if you're low-income) towards a level 2 240V charger -- only as long as funds last, and if you're in their jurisdiction (ie, LA/OC/Riverside/San Bern). Have no idea if they're still doing it, or if all funds are gone or not. Left a message to try to find out for others, but for me at this point, doesn't make sense to install the 240V.

    Edit 2: Heard back from AQMD. The rebate program is still valid for those in LA/OC/Riverside/San Bern, but it's $250 off the cost of the CHARGER (you pay all labor/installation costs yourself) and you have to submit documentations to them showing everything. Link below for others interested:

    Residential EV Charging Incentive Pilot Program
     
    #12 stevepea, May 12, 2017
    Last edited: May 12, 2017
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  13. HPrimeAdvanced

    HPrimeAdvanced Senior Member

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    Bummer! Anaheim does provide all utilities to residents and maybe because in or near Anaheim, we have Disneyland, Knott's Berry Farm, the Convention Center, Anaheim Stadium, The Pond, and a whole bunch more stuff going on, they have the tax base and resources for our relatively small (347,000 people) population to afford doing this sort of thing. My offer stands, Welcome All!!

    .
     
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  14. CharlesH

    CharlesH CA HOV Decal #5 on former PiP

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    The $500 rebate I got in Roseville, CA, was specifically for a installing a home 240V charging station. In addition I got $300 for the car itself.

    Regarding the question about efficiency of 240V charging vs 120V charging; that is actually a reasonable question, since one has to consider overhead in the charging process, not just the total amount of energy put into the battery. It takes a certain amount of power to operate the charger electronics and do the voltage conversion, and that will be a factor of time. I will defer to others for the actual numbers.
     
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  15. PT Guy

    PT Guy Active Member

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    Pennies...or maybe fraction of pennies for the parasitic draw of the charging station.

    A full electric charge saves me about 1/3rd gallon of gasoline, but costs me about the same for the electricity as 1/6th gallon of gas. At that rate how long will it take to pay off a Level 2 charging station? (Hint...I won't live that long.)
     
  16. CharlesH

    CharlesH CA HOV Decal #5 on former PiP

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    I agree that the power usage of the charging station is negligible. I was talking about the energy consumed by the charger, which is in the car.
     
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  17. SaraBBrown94

    SaraBBrown94 Active Member

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    I had a guy that is pretty knowledgable tell me it's cheaper to use the 240 because using the 120v would charge you twice as much as if the car was using both outlets at the same time. He said it had something to do with how the electric meter records your usage.

    Posted via the PriusChat mobile app.
     
  18. Lee Jay

    Lee Jay Senior Member

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    When it comes to electrical things, I wouldn't trust that guy to turn on a light switch.
     
  19. William Redoubt

    William Redoubt Senior Member

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    Please post location and hours of operation!
     
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  20. William Redoubt

    William Redoubt Senior Member

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    Ironically, the phrase, "not the brightest bulb in the bunch" also is related to electricity. If this assertion were true electric utilities would not allow 240 volt loads.
     
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