Tesla has officially launched their long-awaited “Supercharging” network last night to a star-studded crowd in Southern California. (We assume it was star-studded since our invitation got lost in the mail.) The EV network promises to enable Model S and Model X owners to charge 150 miles of range in 30 minutes. What about your Roadster? Sorry, you aren’t invited to this charging party. Have a Tesla and a LEAF? You’ll have to be satisfied with separate but equal charging facilities as the Tesla proprietary charging connector restricts access to Tesla shoppers only. Is this class warfare or do we parallel the computer industry where connectors come and go with the seasons?
What’s the big deal with charging? Let’s go over the Model S’s charging time chart and you’ll understand. From a regular 120V wall outlet the Model S will gain 4-5 miles per hour of charging and consumes about the same amount of power as a space heater. Charging at 41 amps, the car gains 31 miles per hour and consumes as much power as TWO average electric clothes dryers. Charging at 81 amps (a service that many homes with older wiring or smaller services cannot support) the Model S gains 62 miles an hour and consumes more power than an average home’s A/C, dryer, washer, stove, oven, lights and small appliances put together. With a range of 300 miles and a 10 hour charge time at the 41A rate, it’s easy to see why fast charging stations are appealing. Tesla’s Supercharger’s specs are yet to be revealed, but by the numbers it is apparent the system is delivering a massive 90kWh charge which is likely 440V DC at around 200A. An hour of charging at that rate is 70% of the power that my home uses in an entire month.
Is this a Tesla issue? No, it’s an EV issue. If you expect your EV to drive like a regular car, modern EVs are a delight. If you expect your EV to refuel like a regular car, we’ve hit a snag. But it’s more complex than that, you see, only three of the four Model S trims support DC fast charging and the only other EVs on the market with a DC charge port are the Nissan Leaf and Mitsubishi i-MiEV. Except they don’t use the same connector or the same standard. Oops. Adding more complications to the mix are the EVs with no DC charge connector like the RAV4 EV, Volt, Prius Plug-In, Accord Plug-In, Focus, Active E and Coda while the new Chevy Spark is rumored to début a third standard: the SAE combo plug.
Of course, if you think of your car like you think of your cell phone, this makes sense as the phone you bought last year wont use the same charger as the phone you buy today. If you think of this in car terms however it’s like buying a new car and finding out that most of the gas stations have a nozzle that won’t fit your car.
Back to those Tesla charging stations. Tesla opened the first four in Southern California and announced two more stations will go online in October with stations in Las Vegas, Northern California and Oregon by summer 2013 with the 100 station network being complete by 2015. If that network sounds familiar then it should, because the recent settlement in the California vs NRG lawsuit means there will be 200 new CHAdeMO stations in California over the same time frame in addition to the 8 already installed and the 75 commercial stations planned or under construction. It isn’t just California on the CHAdeMO bandwagon however, the Department of Energy claims there are over 113 CHAdeMO stations in the USA and a 1,200+ unit installed base in Japan.
What does this mean to Tesla owners? Until Tesla creates a CHAdeMO to Tesla charging adapter cable (much like they have a J1772 to Tesla cable for use at public AC charging stations), Tesla owners will be restricted to regular AC charging or the smaller Tesla only charging network. On the flip side, Tesla is promising the Tesla charging stations will be free to Tesla owners, positioned next to trendy restaurants and you won’t have to mix with the Leaf owning rabble. You can also feel superior because Tesla’s newer standard charges 80% faster than the 50kWh CHAdeMO connector.
What does this mean to LEAF and i-MiEV owners? It means this is just the beginning of a standards battle. If you bought an EV before this raft of new J1772-connector-toting models, you know what I’m talking about. While CHAdeMO has the lead now, depending on what standard the rest of the industry supports this could change rapidly.
What about the rest of us? If we continue to build more battery electric vehicles and continue to develop batteries that are more and more power dense, you can expect even the snazzy Tesla charging connector to be outdated on a few years. If you expect an EV SUV to deliver 300 miles of electric range, AWD, decent performance, mild off-road ability and Range Rover quality luxury trappings, then expect it to have a battery that is 50-100% larger than the Model S’ massive 85kWh pack. This means you have to either take all the charging rates and nearly double them, or you have to develop a charging method that charges 50-100% faster to keep the same performance.
Of course, just like LEAF owners experience battery degradation caused by repeated use of DC quick charge stations, Tesla owners should be mindful that batteries don’t last forever and the faster you charge them the shorter their life will be.