Although electric cars aren't exactly new, the first ones having been built in the late 1800s, they've taken a while to catch on. In recent times, consumers were limited to odd-looking vehicles that couldn't go far or fast---except for those few individuals with enough money to buy the luxury Tesla sports car.

That's changing with the upcoming introduction of mainstream electric cars like the Nissan Leaf, and mostly electric ones like the Chevy Volt. This weekend, the San Francisco Bay Area Green Drive Expo offered a chance to see some of the latest in this technology and to learn more about what's coming.’

Why has it taken so long for electric cars to become mainstream and within the reach of the average consumer? The answer isn't simple, as revealed in the documentary Who Killed the Electric Car?While it's tempting to blame the oil companies, and they've certainly played a large role, widespread deployment of the electric car has also been stalled by other factors, such as consumers' skepticism. Chelsea Sexton, featured in the documentary and now an electric-car advocate, discussed some consumer worries in her keynote:

Issue: Range anxiety, by far the most pervasive consumer fear, prevents many from feeling comfortable with the idea of an electric car. One man in the audience, who was sure he represented the views of most people, claimed he needs 200 - 300 miles per charge. The fact that 90% of our daily driving is well under the 80 - 100 miles a day that most manufacturers promise doesn't always quell range anxiety. Add to that the reality that you might not get the full range if you're running the air conditioner or heater, listening to music, and have a carful of passengers, and many might still hesitate to buy an electric car.

Answer: If range is really an issue, consumers have options like the Chevy Volt, whose gas engine kicks in when the battery is drained, or established hybrids like the Toyota Prius. For some two-car families, it makes sense to use an electric car as their second car. Or we have the choice to wait till the technology improves. Battery range is currently increasing about 7% a year, and this could speed up.

Issue: Performance is another worry; some people think electric cars aren't as sturdy or reliable as their gas-powered counterparts.

Answer: The cars on the horizon (and even some past models, like GM's EV1) perform beautifully and are well constructed, and people love driving them. The issue is not the technology but consumer adoption.

Issue: Electric cars might be inconvenient.

Answer: It's easier to plug in your car at night than to make a trip to the gas station.

Issue: Electric cars won't cut pollution if we're getting the electricity to run them from coal.

Answer: Numerous studies have shown that even with coal-generated electricity, electric cars can cut emissions by 40%. In areas like California that have many alternative energy sources, we can cut emissions by as much as 90%.

Issue: Discarded batteries, with their toxic contents, are a source of pollution.

Answer: When a battery can no longer be used by a car, it still has 70% - 80% energy left for other uses, such as solar energy storage. We currently pollute more with discarded double-A's than we would with car batteries. And we can extract lithium from old batteries for reuse. In addition, battery technology is likely to change to use different materials, as it has already.

Issue: We lack the necessary infrastructure for car charging.

Answer: Most people charge their cars at home. Building too much infrastructure before it's needed could lead to vacant charging stations, creating a misperception that there's a problem.

Issue: Many cars charging at once in the same area could lead to blackouts.

Answer: If cars are charged at off hours, instead of at peak-usage times, this shouldn't be an issue. Chargers can be equipped with timers to allow for this, and electric companies can provide financial incentives to those who charge at off hours.

Issue: Electric cars are expensive.

Answer: Incentives and rebates for new electric cars can bring the price well within the reach of many consumers. And drivers will save money on gas, since the electricity needed to charge a car battery is much cheaper.

These issues and others need to be addressed by good marketing. Early adopters, prevalent in the audience at the Green Drive Expo, are crucial in showing that electric cars are a viable alternative. People have different reasons for wanting electric cars---financial, technical, environmental, sometimes even a coolness factor. But as Sexton noted, "I don't care what brought you to the table---I care about the table." We need to get electric cars on the road and make them mainstream. And now we're finally taking real steps in that direction.

The energy collective