In the beginning, the use of Tesla's nascent network of Supercharger DC fast-charging sites wasn't going to be free.

Not for owners of the less-expensive Model S 40 and 60 versions, at least: if they wanted to use the Supercharger network, they paid a $2,500 fee up front.

But demand for the lower-range versions of the luxury electric sedan was low, and eventually Supercharger access was simply bundled with every Model S.

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Enter the Model 3, the 200-mile, $35,000 electric car that Tesla Motors hopes to produce in huge volumes starting in the second half of 2017.

A shareholder at Tesla's annual meeting yesterday—who had put 150,000 miles on his Model S in a single year—asked how the Supercharger network could handle demand once hundreds of thousands of Model 3 cars were on the roads.

Tesla CEO Elon Musk responded, according to The Wall Street Journal, that the "obvious thing to do is to decouple" the cost of using the network "from the cost of the Model 3."

Tesla Motors Supercharger network in the U.S. - map as of March 2016

Tesla Motors Supercharger network in the U.S. - map as of March 2016

In other words, Model 3 buyers would likely have to pay a similar fee up front to that once charged to lower-end Model S buyers.

In Musk's words, "it will not be free long-distance for life unless you purchase that option.”

The CEO didn't provide any details of the cost to be charged to Model 3 buyers for unlimited use of the Supercharger network.

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That information will presumably become apparent once features, options, and pricing for the various Model 3 versions are revealed closer to the car's on-sale date.

The Supercharger network has no payment mechanism; Tesla owners can simply drive in and plug the cable into their cars without any validation on their part.

Musk added that such a cost would "still be very cheap, especially in comparison to gasoline," a claim immediately attacked by at least one Tesla skeptic.

Tesla Supercharger site with photovoltaic solar panels, Rocklin, California, Feb 2015

Tesla Supercharger site with photovoltaic solar panels, Rocklin, California, Feb 2015

Anton Wahlman, an investor who frequently criticizes the company, its cars, and its management, noted that a 50-mpg Toyota Prius using gasoline at a price of $2.33 per gallon costs less than $0.05 per mile to run.

Assuming a Model 3 delivers about 3 miles per kilowatt-hour at highway speeds, and the nationwide average price per kwh is $0.13, that comes out between 4 and 5 cents per mile as well.

The per-mile math changes, naturally, if gasoline costs go up—and it changes radically if Supercharging is paid for with a flat one-time fee, as it was three years ago.

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Each owner will have to decide, of course, whether free Supercharging over the life of the car is worth what will likely be a four-figure fee. We'd expect most Model 3 buyers to opt in, though.

Tesla has demonstrated the potential of DC quick-charging to make long road trips possible in 200-mile electric cars far better than any other maker.

It's an advantage that we suggest most Model 3 customers won't want to pass up.


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