A niche market in the EV world is Electric Plug-In Conversions, converting a run-of-the-mill hybrid (e.g. a used Prius) to a plug-in hybrid.
Minnesota's local converter ReGo Electric Conversions is holding an open house bright and early August 9, 2011 from 7:00 A.M. to 11:00 A.M. at 5925 Nicollet Ave South.
They tell me a conversion is $4995. This is a factor of 10 cheaper than a Chevy Volt. Still, at what price of gas ($/gal) is this economical?
They claim to recover about 2/3 of the cost at $3.50/gal (which is around the average so far this year). It'd require going up to $5.50 or $6.00 to recover the whole cost.
Of course, the average cost for a new car in 2010 was $29,217, according to the Detroit Free Press. A base Prius runs somewhere around $23,500, so even with the extra batteries, it's only an average vehicle cost.
Expect to see a $5,000 tax credit for conversions in the offing sometime soon...