It's dangerous to assume, as the saying goes.

And a lot of assumptions about why people buy electric cars are wrong--including that they only do so because they're "green," meaning to help the environment.

Now a new attitudinal survey shows this isn't much true for Tesla owners and fans.

A study by (via AutoblogGreen) compared and contrasted Toyota Prius hybrid owners and followers to those for the Tesla Model S.

Just not so green?

The Prius people, it said, are "keenly interested in Eco-friendly subject matters and Social Change."

The Tesla folks? Here's what said:

Environmentalism is not a substantial area of interest in the Tesla Model S Interest Graph.  This may indicate that Tesla interest is driven by the technological or aspirational aspects of the brand rather than it’s [sic] environmental benefits.  

This is supported by the fact that, while the Tesla audience is 8.5 times more likely to be interested in fuel efficiency than the general population, Prius fans are 4x more likely to be interested than the Tesla folks (34x general population)

Many motivations

This only reinforces the point that there are several different motivations to buy a plug-in electric car, among them early adoption of new technology, energy security, and lifetime cost of ownership.

Yes, there's the green thing too--but it's far from the only motivation.

We'd like to see more data on Tesla Model S buyers as the car spreads beyond its Silicon Valley stronghold.

Meanwhile, Tesla Motors CEO Elon Musk underscored the point yesterday, on a call following yesterday's Tesla earnings report.

In response to an analyst's question about the luxury sedan sector, he discussed the variety of trade-ins and cars replaced by the Model S.

From Odyssey to...Model S?

Musk pointed out that no single car model represented more than 10 or 11 percent of the vehicles replaced when buyers opted for the Model S.

While "premium sedans and hybrids are the big ones," they're far from the only models.

2012 Toyota Prius Plug-In Hybrid, production version road test, San Diego, CA, Jan 2012

2012 Toyota Prius Plug-In Hybrid, production version road test, San Diego, CA, Jan 2012

You might have expected the Toyota Prius to dominate, or at least represent up to half the total--as it did, for example, among Nissan leaf intenders.

Not so.

The Prius was only 10 percent or so of the total, followed by the Mercedes-Benz E-Class (a mid-size luxury sedan) and the Nissan Leaf (a compact electric hatchback).

Then there were several unexpected vehicles: The Honda Odyssey minivan, Volvo XC90 large sport-utility vehicle, and Volkswagen Jetta compact sedan each represented 4 percent of trade-ins, followed by the Honda Civic compact sedan at 3 percent.

It's an "incredibly wide variety of cars traded in for the Model S, Musk said, and specifically "not just large luxury sedans."

In other words, remember what happens when you assume.

[hat tip: Brian Henderson]


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