Fast Charging an EV: AC/DC Questions and Renault's Answers

Very interesting, Thanks Laurent and I especially liked all the photos.

Problem for the US market is AC Propulsion will SUE anyone trying to do that here... Yes I understand that, since the car has to have regeneration anyway, why are we duplicating hardware when it already exists? Several "Generalists" have asked why we don't do this automatically, and, its an OBVIOUS, very reasonable question.

Answer: Because they'll be tied up in Law Court.

Tesla, having to date the largest batteries and most powerful electric motors out there, uses substantially one or for $1500 more (and even this ignores how you are going to get the juice to the side of the car), TWO seemingly redundant chargers to work, on ostensibly the most modern call going (MT's Car of the Year). They do this "somewhat silly " thing because they don't want to be Sucked Dry by AC Propulsion who has the patent. I've said before this idea isn't patentable since its so obvious as mentioned. But Tivo has patents on trivially obvious things also. So we have to work with the Hand of Cards that we've been dealt.

Another USA issue is Your fast charger Juice (63A, 230Y/400 3 phase),nor the American or Canadian Analogue, is not that common around here. Granted a small easily solvable problem.. But it is another straw for the Camel's Back.

@Gorr

Its even worse than you mention due to that horrid J1772 standard which looks like we have to live with for decades to come. Even when the hardware matches, the car and charger dock don't due to this horiddly written, non-standard Standard.

Thanks very much, Laurent, for what is the best explanation I've read so far regarding the Renault charging system . . . and to other here for commenting and providing clarity on certain points.

gorr asks . . . "What do you do if you want to charge it with solar power? Solar is dc, so from dc to ac then ac to dc and then from the dc battery to ac motors for the wheels. All that works but, sadly, all have a different incompatible recharging standards."

It's true, gorr, that there are a variety of different EV charging standards out there and this is a source of ongoing frustration (sounds as if Renault really has it well thought out, though) and, yes, there are typically multiple DC-to-AC and AC-to-DC conversions going on between charger and rotating motor, whoever's system you're examining . . . but a little clarity, perhaps regarding solar PV.

Yes, solar PV is DC. In it's purest form, those panels would be directly charging a bank of stationary batteries, probably either 12V or 24V. Those batteries would be powering devices in a small home . . . lights, refrigerators, etc. All those devices would have be 12 or 24V DC in nature. This was how it was done in the early days of solar . . . completely autonomous and off the grid. Trouble is, you were totally dependent on having those panels collect enough sunlight-generated electricity to keep those batteries charged and the you had to be frugal enough not to run them down before the sun came up again. These off grid PV systems can still be found in remote and rural areas, where power lines simply don't run.

Almost all urban residential solar PV installations today, however, tie the DC output of the panels to the pre-existing AC fuse/breaker box by way of an inverter . . . hence, a grid-tied system. It's possible to employ banks of backup batteries, but most grid-tied PV systems dispense with this. You are, thus, dependent on power coming into the house from your power utility. So, even if you have massive numbers of PV panels on your roof - and you're operating a grid-tied system with no battery backup - a power outage will take away all your electricity until the problems are attended to by the utility company.

The flip side of this, though, is that under more typical circumstances, you may producing more electricity with your panels than you are using at any given moment. You then have an opportunity to "sell back" the electricity you make to your utility company. Also . . . all the devices in your house can be just like any other modern residence: AC powered. You don't have to worry about sourcing specialized "off grid" 12 or 24V television sets, light bulbs and the like.

Think of a grid-tied home PV system as a sort of Plug-in EV, like a Chevy Volt. On a sunny days, your power will be almost exclusively generated by what your panels are putting out. But the "gasoline" automatically kicks in when it's cloudy or rainy. You then start getting most (or all) of your power from what's coming in from the grid.

Getting this discussion back to EV charging from your solar PV panels: It would require a very large array of panels and consistently sunny weather to do this with an off grid system. I don't know of many off-grid homeowners who are also EV owners. An urban home owner with a slightly smaller panel array that's tied to the grid, though, can comfortably plug in the EV with confidence that charging the car - even if the sun isn't shining at that particular moment - is probably going to be possible. Indeed, that EV charging scenario might be happening at night. The next day, which might be particularly sunny, might find the homeowner back to generating more PV-generated power than he's using. This offsets what was used to charge the EV the night before.

@Fernando M

Not to seem dumb but I'm not sure what point they were trying to make by the link. The 20 kw (that's a bit of a dream since its only at 250 volts, uncommon here. 19.2 kw @ 240 (still rare to be that much at 80 amp drain), and a more reasonable 16 kw @ 200 volts for commercial installations), is not considered by Tesla S to be a fast charge.. Its still a slow "level 2" charge by their standards.

@Modern Marvel Fan

"....What I am surprised is the fact that NO EVSE maker has came out with an "universal" EVSE that can take in any input A/C power range. ..."

The GE DuraStation (by far the most popular EVSE in WNY) has a 30 ampere output at anything from 104-125, and 190-255 volts (the control transformer in the unit must be set for either range). But I think you'll agree this is a pretty wide range. What I don't understand is home come VEHICLE onboarchargers don't accept 277 volts. Maybe because its only available in the US and Mexico?

They should figure out one standard for every electric plug-in cars sold in north-america.
As of yet this is not done and it apear as some electric cars are introduce on the market that it add many different recharging standards. I won't buy any electric plugin car till there is just one recharging standard.

Tesla is building free superchargers that are incompatible with even their smallest battery cars. they will lose almost a billion dollar and few will utilize them , this compagny is in danger to go bankrupt anytime.

Please follow the easiest route. The electric grid is 110 volt ac and then is move up with 110 volts increment to 220 volt ac, 330 volt ac, 440 ac, etc, up to 750 000 volts ac in the highest of electric lines. So you just have to plug ac voltage to the car and the charger is inside the car already adapted to all the circuitry of the car. for fast charging 440 volts ac directly pluggued to the car seam a very good efficiency.

Please scrapp any fast chargers already installed or on their way to be installed like the new sae protocol, chademo, tesla supercharger, etc. Use a simple electric wire that come from the grid and plug it directly into the electric car where the charger is inside.
That cost way less as if 5 electric car show-up in the future at the same time into a fast recharging station, all it will take for the station is just 5 ac 440 volts 60 hertz electric wires. That cost 40 time less then 5 superchargers or 5 sae chargers or chademo.

@Benjamin Nead

Glad someone is finally thinking longterm about minimizing numbers of different standards. I dont like the combo J1772 thing since it apparently uses different wires for either Ac or Dc and therefore one pair is always unused. This makes the cable heavier than it need be.

My own 150 kw fast charger Idea (2 # 4, 1#8 formed in an outer shield, and 2 # 18 controls) is probably the heaviest most small women would want to deal with assuming a 25 foot cord.

@Martin Winlow

Ok man, this is taking political correctness to a bit too much of an extreme. I in no way denegrate women by saying there is such a person. On another blog someone used such a woman as a typical example of why what I wanted to do was impossible. Incidentally, since the US General Electric Company is actively marketing the 3 phase 400 volt 32 amp DuraStations all over the UK and is offering no remotely similar products (other than 100% single phase) for the North American market, obviously there are EV's available in this market that can utilize it (there are *NONE* in the North American market) all your information given to date regarding no 3 phase being available has therefore ostensibly been incorrect.

I think the current state of technology means that a 100% EV is not going to meet the needs of most Americans as an *only vehicle*. However most American households have multiple vehicles, and as a second or third vehicle a 100% EV works perfect. Drive the EV on all the local trips around town, and use the ICE for road trips...

There are a few families who can make an EV work as an only car, and if a family doesn't do a lot of road trips - they can always rent a car when they do need the long range occasionally.

But right now, EVs make perfect sense if they can be used as the around the city car...

@Martin Winlow

That was what we'd call here a left handed apology. There was no sexist remark made, period. There was nothing in the slightest condescending about any statement I've made. Why this is important is we shouldn't 'train' people in politically correct speech.

I'm of Brtitish Extraction, but Britain is pretty far gone. I at one time listened to the BBC, and find almost all the presenters Insulting and boorish, and in general much too self-important. Like the USA, there is almost no investigative journalism going on, and all your polititians have sold out, as have ours. We have little Freedom of Speech left, (you have less), and our Constitution has been allowed to become pretty much a Dead-Letter.

I don't comment on this much, but as regards EV's it looks like fewer and fewer of us Americans are going to be able to afford them. The Deindustrialization of the United States is Continuing, which is a crying shame since Wealth is generated on the factory floor. The current energy boom in the US will at least retard the economic decline by 5 - 10 years.

. The news of all the layoffs at Boeing was basically sequestered until after our election. Not so surprisingly, Russia Today, RT.COM does a better job reporting the state of our cities than our own Lame Stream Media, although Frontline and the BBC did pick up an independently produced film on "Poor Kids", which is a microcosm of our future 3rd worldism.

So, no offense Mr. Winlow, I'm going to keep talking in the manner I'm talking. I talk this way to encourage other casual viewers of PlugInCars.com to continue to be UNAFRAID of speaking their minds. Liberty is rather like a muscle. If you don't use it you lose it. We don't have much left, so its time to get exercising.

@Benjamin Nead

We're friends but please don't trivialize a serious subject. If I can put up with your Global Warming statements you can put up with my Liberty ones.

The Black Helicopters are all in Austin, Tx for Formula One.