My Nissan Leaf Forum

Or if they figure out how to use the motor windings, as part of the charging circuit (the way that AC Propulsion has figured out, used in the BMW Mini E), they could get up to nearly a 18KW onboard charger...

I have no need for a 6.6kW charger, but if it means no more hump in the trunk I'd definately want one for that reason only.

Sorry, you will not see this happening, even though it is elegant, simply because there is no Galvanic isolation.

-Phil

Consider what the transformer sees. Out of a group of homes, how many are drying clothes at the same time? How many are baking at the same time? How many ,even, have their central AC compressor running at the same time? Compare to an EV where, absent a strong TOU incentive, most everyone is going to plug in when they get home, for a constant multi-hour charge, which is going to be superimposed on what was already the peak load.

I don't agree; most people will charge at off-peak for cheaper rates using timers. This will be the dead of night when A/C loads are lowest and nothing else is happening. The minimum I typically have seen deployed in the last 30 years is a 25kva transformer per 4 houses, and many are now 40 kva or more. There are some areas with really old infrastructure, but EV rollout isn't going to happen all at once, so the utilities will have time to slowly upgrade.

-Phil

I put an end timer of 8am on my car. I don't have TOU, but I'd rather load the grid when it can best be utilized.

I agree almost exactly except for the last statement "Compare to an EV where, absent a strong TOU incentive, most everyone is going to plug in when they get home". I don't do that and I don't have any TOU incentives and have solar to cover the Leaf to boot. I think in the 2 months I've been driving my Leaf I've only done that twice. A couple of other times, it would have been really nice to have used 6.6KW (or QC) so I didn't have to drive my ICE car.

I think the average EV owner is sophisticated enough to know that isn't the best way to load up the grid and at least for the Leaf the timers are very easy to set and forget once you get used to them. If the Leaf didn't have timers, I'd use the one built into my EVSE. Don't sell us short.

I think a far bigger worry is the amount of new and existing AC units running at peak load that we are going to see as things continue to warm up. I don't think EV peak load will be a worry for decades compared to other loads. I'd love to see EV adoption ramp up to the point it did become a worry, and as you mention, a strong TOU incentive will change most folks behavior w/o any change to the grid other than smart metering.

Note, I said "absent a strong TOU incentive"...

Imho, the average EV owner today is a very different thing than the average EV owner under mass-adoption. Today it doesn't matter to the grid when *we* are charging. When there are a EVs in California, it will start to matter and those owners are not all going to have the same sensibilities as the early adopters.

This is a self-regulating problem. If the "non-sensible" EV owners start all charging at peak times, the utility will have no choice but to implement high peak rates, then their wallet part of their brains will adjust said behavior, either that, or they blow their (and their neighbors) transformer fuse, and are without power for a few hours at a time over and over until the utility upgrades it! =)

-Phil