I remember seeing some comments here that since a level 2 charger charges more quickly, some electricity is saved relative to a level 1 charger. Is that correct? Anyone know how much less electricity a level 2 charger uses to charge the Clarity PHEV?
I don’t have a quantifiable amount for you, but I don’t think the efficiency gain of the Level 2 charging is big enough to make a significant difference. (Nor is the charging rate fast enough to significantly affect battery health.) It’s mostly for the convenience of shorter charging times that let you charge between trips if driving a lot in one day and for staying in the lowest cost rate if you’re on a TOU rate plan. Some Level 2 EVSEs also have apps to track kWhs and cost which was one reason I paid for a Level 2. And one is my favorite quotes: “A difference that makes no difference is no difference.”
I have both level 1 and level 2 chargers here at my home. If there is a difference in power usage between the two that does not go into the car's battery, I can't think of a way to measure it. And what @KentuckyKen quoted.
The other advantage of a level-2 charger is that preconditioning is much more robust with the level-2. This was my primary motivation for buying the charger; in cold weather it makes a huge difference. I already had the 220v plug in the garage. Remember that the charger isn't really a charger in the sense that it is just a means of delivering voltage to the charger that is in the car. The efficiency of that circuitry is unlikely to vary much with the difference in voltage. You're not going to save any significant money on electricity by switching to a level-2 charger, but if you need to charge in less than 12 hours then that's a strong motivation.
I really don't think it is enough to make a difference either, but the losses from the meter to the car (including the EVSE itself) should be half as much with level 2 as level 1 for the same amperage (16A level 1 vs 16A level 2). Losses per hour are the same but the level 2 will charge in half the time. If you compare 16A level 1 to 32A level 2, then the losses for level 2 are just slightly less, but of course level 2 charges a lot faster. Losses per hour for the level 2 are 4 times that of the level 1, but the level 2 will charge in like 1/5 of the time of the level 1. But I agree that this is probably counting pennies.
I would assume that the perception is there erroneously,.. and that any difference is on a micro level,. likely barely measurable. The error in the assumption would be understandable. Because most electric motors can benefit from the higher voltage of 240, it is often assumed that motors wired 240 are more efficient. Again, this is not really true from an electrical consumption stand point, or power generated, but for a motor that can be wired either way, wiring it 240 will mean the additional voltage will help get the motor started faster. (start up demand is much higher than continuous running) Therefore a motor wired 240 is "better" than wired 120. This idea has been assumed to mean that better equals more efficient. None of that would apply to the power running to you car's charger. Where 240 is ALWAYS "more efficient" is in power loss due to length of run/wire gauge. By doubling the hot leads, you can move twice as much amperage through a specific gauge cable because you have doubled the number of conductors.
Thanks @MNSteve, I forgot about Level 2 making preconditioning so much better. I only used my OEM charger for a few times before I got my ChargePoint so I’ve been taking the superior Level 2 preconditioning for granted. I feel sorry for those who have to precondition in extreme temps with just the OEM Level 1.
