Friday 28 October 2011

Disagreement over standards inhibits fast-charging for electric cars

Disagreement over standards inhibits fast-charging for electric cars:


The other issue inherent to electric cars, in addition to their limited range, is how long it takes to recharge them. A “quick” 30-minute recharge could make a big difference for electric car drivers, albeit it’s still longer than a fill-up. And one reason such fast chargers have been slow to appear—other than cost, who pays for them, and how do they become profitable—is that it can be hard to get a bunch of car companies to agree on anything. So when seven automakers agree to a new standard for charging, it sounds like a breakthrough. Except when the rest don’t.



That’s what happened last week when Audi, BMW, Ford, General Motors, Mercedes-Benz, Porsche, and Volkswagen all agreed on a standard plug to use for “fast-charging” their electric cars in the United States and Europe. A “fast” charge can recharge an electric car to 80 percent of its full capacity in about a half hour. Charging any more quickly or fully would damage the battery and dramatically reduce its lifespan. The new plugs will use the standard SAE J1772 120/240-volt plug above two pins for fast charging when it’s available.



But Nissan, along with Mitsubishi, Tesla, and others, already use a different Japanese standard called ChaDeMo. The Nissan Leaf includes a ChaDeMo-compatible charge port on the SV trim level; it is otherwise optional for $700. (The Leaf has the two chargers side-by-side inside the charge port door on the nose.)



There are very few public fast-charge stations installed in the United States, and all so far use ChaDeMo plugs. Now that seven automakers have agreed on a different standard for the United States, Pacific Gas & Electric, which owns the California station, has reportedly shut it down pending certification of the charger by Underwriters Laboratories.



This will leave hundreds or thousands of Nissan Leaf and Mitsubishi i drivers without a fast charger to extend a trip from Sacramento to San Francisco. This inconsistency in charger standards is one of the things that stymied the adoption of electric cars in the 1990s. Back then, with every automaker using a different charger plug, no EV driver could count on being able to use any public charger they encountered. So it was impossible to roll out a compatible public infrastructure.



Now that 240-volt chargers have a standard plug around the world, some cities can begin rolling out these so-called Level 2 chargers in public locations. But it looks like it may be some time before they’ll be able to do the same with DC “fast” chargers.



See our guide to alternative fuels and cars.


Source: Google Reader

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