It makes plenty of sense economically, but we Americans do not understand amortization of costs. Two examples: cell phones and electric cars. In the former case, people feel they are getting a great deal on a free phone but in fact the carrier is merely splitting the cost over the term of your contract (this is the principal reason for contracts and the early-termination fee, I think). In the latter case, you pay a large sum up front, but consider that gas costs about $4 a gallon, so let's consider a more reasonable example:
Chevy Malibu = $20,000
Gas for 36K miles over 3 years (standard lease term) = (36000 / 22-30 mpg) * 4 = $4800 - $6500
Converted Chevy Malibu (aka "Volt") = $27,000 - $30,000
Electricity to power, assuming no fuel and 40 miles / 16 kWh charge = $1440 (= $.10/kWh)
So the Volt has a higher TCO (Total Cost of Ownership), but not by much. Extending this to 8 years, the expected warranty life of the Volt, the TCO becomes:
Malibu = $ 32,800 - $37,000
Volt = $ 33,840
So even if fuel prices stay low (they won't), you are only paying a slight premium for the Volt over the life of the vehicle. We can only assume that electric cars will become cheaper over time as well, whereas the gas guzzler really won't, bringing greater price parity.
So using the above numbers, is it worth $125/year to cut emissions and dependence on foreign oil? I think so! You can easily save $125/year in energy costs by switching to CFL's, putting better insulation on your hot water heater and in your attic, and making your next file/print server a VIA-based Mini-ITX system.