There's a lot of interesting breakthroughs in electric cars. New models coming out have greater capabilities than those that came before. There still are advances that will be needed for the electric car to gain widespread acceptance and possibly to replace the internal combustion engine.
The biggest obstacles may be the distance available on a single charge, and the rate of charge. Current electric cars are just fine for those who only use the car for city driving and have a convenient place to plug their car in while parked.
But they may not be an option for those who drive distances greater than can be reached on a single charge. They may still be an option for such people if they have a second car.
They may not be an option for people who live in an apartment and park on the street, or in a parking lot without access to an electrical outlet.
Still, the electic car an option for many, and these early adopters are helping us get to the point where the electric car is an option for everyone. The Tesla's 250 miles on a charge is a great step forward. Future improvements in battery technology will likely allow even more milage on a charge, or allow less batteries to be used, lowering the weight and thus the efficiency of the car.
The charge time of the vehicle is another issue. At 250 miles on a charge, you can drive cross-country if you wanted, but you would need to charge up somewhere. We will need improved on-the-road charge capability. As more electric cars are on the road, I expect that this demand will be met. We will need to charge up our cars, and someone will be there to provide that service. Future electric cars will need to have the capacity to accept electricity faster, and gas stations will need to add electric capability to sell us that electricity.
While the American manufacturers seem uninterested in meeting the demand for electric vehicles, it is encouraging that other companies are willing to step up to meet this demand. Hopefully, the American manufacturers will step up to the plate, once it is sufficiently clear that America is trending electric.
Significant increases in electricity demands would require more electrical production and upgrades on our electric grid. These upgrades to the grid are sorely needed in any case. Alternative energy sources would be a great aid to the environment, but even if the energy were produced by conventional fossil fuels, it would likely involve a net decrease in energy consumption, as it is more efficient to run cars on electricity than on gasoline.
I get decent gas milage on my 91 Civic, and it has a lot of years left (knock on wood). But when it comes time to replace it, I would like the option of an electric car that I can take on a long drive and refuel quickly on the road. There's a decent chance my Civic might last long enough, and I look forward to it. The Tesla Roadster isn't the car that I would buy, it's too expensive, and two seats won't do for me. But many new advances are expensive at first, and suceeding generations of technology become cheaper and cheaper. There's a decent chance my Civic might last long enough, and I look forward to it.