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Renault Zoe uses a fundamentally different charging method

Renault Zoe uses a fundamentally different charging method

I was reading "DUAL CHARGER 22 KW - YESTERDAY'S TECH" which discusses the higher AC charge rate of the Zoe. I just realized that the Zoe uses a fundamentally different charging method which I believe can change how cars are charged. I think this method deserves a topic of it's own.

As I understand it Renault has not added a 43 kW on board charger, they used the existing inverter that drives the cars electric motor. That's why they call it "Chameleon". I assume they disconnect the car motor and connect AC shore power to the inverter output. Power the battery just like regen braking. They have reduced the car weight and increased the charging ability to 43kW.

If Tesla would follow this system they could get rid of the one or two 10kW chargers and increase the possible AC charge rate to 380 hp = 280 kW (P85D 691hp = 500kW). If this system comes into wide use there will not be a need for DC charging stations at all, even superchargers. Why have a 130 kW DC charger when you have a 280 kW charger already in the car. Tesla would just need to have 250 kW AC outlets stations for the travelers.

Another benefit of this system, the inverters are already designed to flow power both ways. You now have a home generator for no additional cost, already plugged in ready to go. Drive to your supercharger, fill up and bring 85 kWh home to keep the lights on. Run your house for free for ever ha ha. Utilities could pay you to power the grid to avoid brownouts and cover peak loading.

Of course major problems exist to make this conversion. The rated frequency of the inverter being one, I doubt the Tesla inverter can efficiently operate at 50/60 hz. Power conversion and motors reduce weight by operating at higher frequency's, operating down in the 60 hz range would come with higher weight in the drive train. Yes, I know the regen braking is limited to 60kW, not sure why, the inverter can operate one direction at 380 hp, should be able to operate in reverse at the same power level. This is however a very interesting concept for charging electric cars, perhaps Model 3 will use this system.

DTsea | November 11, 2014

So you have proposed the ultimate supercharger freeloader scenario: charge on Tesla's dime for free then run your house off the car?????

Have you ever heard of killing to goose that laid the golden egg?

DTsea | November 11, 2014

Oh and sell power tesla paid for by k to utility at a profit?

I hope you are kidding but it is not funny.

DTsea | November 11, 2014

Back to utility

milesbb | November 11, 2014

DTesa
To me bringing home power from a supercharger was an amusing sideline to the possibility of the Car being a home generator. Yes the "ultimate supercharger freeloader", I like your description. Clearly this will never happen, just like charging at 280 kW using the motor drive inverter. With Tesla monitoring of the cars they will always know where and how supercharger power is used, Tesla will turn off access to any abuser. The Goose should be safe. Sorry you did not think the concept was amusing. I live 280 round trip miles from the nearest supercharger so I could bring home maybe 5 KWh if I drove very very slowly, 50 cents worth of electricity for a day's worth of driving.

Storing and reselling power back into the grid at higher rates could be an added value of any electric car battery. The car could be making you money while you are away on vacation. Tesla has battery pack systems and are proposing to do just that.

DTsea | November 12, 2014

Well, lots of people who live in cuties are using superchargers for all their charging so the freeloader scenario is not farfetched (because they live near the SC.)

Since regeneration is limited to 60kW I would imagine inverter-as-charger would be limited to that.