It's now clear that much greater numbers of plug-in electric cars will be sold in coming years and decades than have found buyers to date.

With battery costs falling faster than expected, and toughening regulations in China requiring higher volumes of electric cars, the onus is on the world's carmakers to step up and sell them at a profit.

But how fast will the transition take place?

DON'T MISS: When will major buyer demand for electric cars arrive? Poll results

Cars with plugs today make up roughly 1 percent of the global auto market, which is closing in on 100 million new vehicles a year.

At some point, the industry expects a "hockey-stick curve" as battery prices fall enough to make electric cars with 200 miles of range price-competitive with gasoline vehicles of similar size and features.

That may not happen until 2025 or later, by some estimates, but it's now likely visible on the far horizon. As we enter the 2018 model year, remember, the cars of 2025 are only one full model cycle away.

We were curious to see how optimistic our Twitter followers were on the pace of that change.

We asked when they expected global sales of electric cars to be equal to those of gasoline and diesel models.

The survey results suggest that participants are ... well ... very optimistic.

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More than one-third (38 percent) of survey respondents said sales of electric cars will equal those of gasoline cars by 2025.

Even assuming that encompasses both battery-electric and plug-in hybrid models, that means an increase in sales of those cars by 50 times in just seven model years, from 1 million to 50 million.

Almost another third (30 percent) of participants said it would happen by 2030.

2017 Tesla Model S

2017 Tesla Model S

The remaining two choices were far less popular: just 15 percent said it would happen by 2035, while 17 percent didn't expect it to happen until 2040.

Predicting the future is always tough, given unpredictable external events, politics, advances in technology, and many more factors.

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But given that automakers who launch new models this year or next likely have five- to seven-year product cycles already mapped out for them, count us among those who think that 2025 is overly aggressive.

That's just our 2 cents; your mileage may vary,.


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