The year 2012 is looking like a huge one for the introduction of electric vehicles. This includes cars that are fully electric, like the Nissan Leaf, and those that are plug-in hybrids, much like the Chevrolet Volt, which operates as a plug-in electric but also has a gasoline engine.

In this year's State of the Union address, President Barack Obama reaffirmed his desire for there to be 1 million advanced-technology vehicles on U.S. roads by 2015.

Anyone could be forgiven for thinking that electric vehicles have gone mainstream. But, in reality, we are not there yet.

"They are plausible because they are already in the market. They are feasible because you can charge them up overnight at your house," said Michael Omotoso, senior manager for global powertrain at J.D. Power and Associates.

If you can sense a "but" coming, you are right.

"We expect commercial success to be very limited for the first 10 years, because we don't have the infrastructure yet," he said.

A J.D. Power study in late October titled "Drive Green 2020: More Hope than Reality?" found that future global demand for hybrid and battery electric vehicles "may be overhyped."

The company estimates that only 20,000 of the 12.5 million vehicles expected to be sold in the U.S. this year will be pure battery-driven electric vehicles. That number has since been reduced to 15,000. (Nissan sold 452 Leafs through the end of March.)

J.D. Power expects 12,000 plug-in hybrid vehicle sales this year. (Through the end of March, Chevrolet sold 1,210 Volts.)

Several other studies and surveys have looked at some of the issues that could hinder widespread acceptance of electric vehicles despite the interest in them.

One out in February — "Plug-in Electric Vehicles: A Practical Plan for Progress" — by a panel working with Indiana University, noted that without another global spike in oil prices, consumer demand might be limited to enthusiastic early technology adopters and relatively affluent city dwellers because of uncertainties about the new technology.

Early adopters who were the first to buy conventional hybrids 10 years ago will be the first to buy electric vehicles and plug-ins, Omotoso said.

He thinks it will be more than 10 years before mainstream buyers start buying electrics and plug-ins.

Adding more models in more segments should help increase sales of electric vehicles, much the way it did with conventional hybrids, Omotoso said.

"The first few years, we only had the Honda Insight and the Toyota Prius, and that's why hybrid sales were very small," he said. Now that there are hybrids in all market segments, sales have increased.

A study undertaken by the Center for Automotive Research in Ann Arbor, Mich., estimates sales of electric vehicles, plug-ins and fuel-cell vehicles will nearly double, from 77,000 in 2012 to 140,000 in 2015.

A Consumer Reports survey late last year summed up some of the concerns of those mainstream buyers. In fact, 94 percent of the 1,713 adult vehicle owners surveyed by Consumer Reports National Research Center find electric cars and hybrids lacking in some way.

Of those surveyed, 66 percent cited a high purchase price as the chief disadvantage; 60 percent were worried about inadequate refueling or recharging infrastructure; and 58 percent worried about limited driving range.

When it comes to range anxiety, the all-electric Leaf, which never uses gasoline, can go 100 miles on a single charge. Consumer Reports' April issue, though, found the range severely restricted by electric heaters that gobble up kilowatts during cold weather. During a cold snap, the magazine reported, the Leaf averaged 65 miles on a single charge.