Anyone who watches even a little television knows that automakers take advertising seriously—and do a lot of it.

The seemingly-never-ending stream of commercials keeps their brands in the public eye, and helps them sell cars to the subset of viewers in the market.

But if you think that electric cars are generally not represented in that stream of ads, you're correct.

DON'T MISS: Nissan Leaf ads poke fun at Tesla Model 3 reservation queue

The auto industry simply doesn't put much effort into advertising electric cars, according to a new analysis of ads from the Sierra Club.

That conclusion is based on 2015 advertising data shared with the conservation group and other by Northeast States for Coordinated Air Use Management.

Data was compiled by CompetiTrack and Motor Intelligence, two companies that track advertising activity.

2017 Ford Focus Electric

2017 Ford Focus Electric

Analysis showed that automakers tend to run fewer ads for electric cars than comparable gasoline models.

In a straight comparison of two versions of the same car, Ford advertised gasoline Focus models in about 4,750 instances on cable and broadcast TV to national audiences, but only advertised the Focus Electric about 200 times.

Mercedes-Benz advertised the C-Class sedan about 1,400 times nationally, but didn't advertise its B250e electric car to a national audience at all.

ALSO SEE: Top Electric-Car Advertisers: Nissan And, Surprise, Kia--Chevy Not So Much (Dec 2014)

Granted, both the Ford Focus Electric and Mercedes B250e are low-volume models that are only sold at certain dealerships.

But what about a car that is sold nationwide, and is in fact the best-selling electric car globally?

According to the data, Nissan only advertised the Leaf about 1,750 times to nationwide to broadcast and cable TV audiences in 2015, compared to about 3,500 times for the Sentra compact sedan.

2017 Chevrolet Volt

2017 Chevrolet Volt

The Chevrolet Volt plug-in hybrid is another fairly high-volume model, but it only appeared in nationwide TV advertising in about 200 instances, while the Chevy Cruze appeared about 700 times.

However, Chevy did advertise the Volt nearly 800 times to California audiences, playing to the state that accounts for more plug-in car sales than any other.

MORE: Electric-car shopping far too hard; dealers, carmakers can improve, says report

Conversely, Volkswagen spent nearly twice as much on TV ads for its e-Golf in the Northeast than it did in California. It did not advertise the car at all nationally.

The e-Golf is only sold in a handful of states deemed by VW to be sufficiently electric-car friendly, a group that includes California and most of the Northeast.

2017 Volkswagen e-Golf

2017 Volkswagen e-Golf

The analysis of ads follows a Sierra Club survey that found dealerships aren't particularly enthusiastic about selling electric cars.

After visiting a total of 308 dealerships in the 10 states that have adopted California's stricter emissions standards, volunteers noted issues such as lack of inventory and sales staff that appeared unfamiliar with electric cars.

The enthusiastic promotion of electric cars by automakers and dealers is essential to widespread adoption.

Because even if electric cars are widely available, fewer people will be inclined to buy them if no one is making the persistent sales pitch that they're out there and available.

[hat tip: Brian Henderson]


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