"People are choosing hybrids over similarly priced small- and medium-sized conventional cars, which are not far behind hybrids for fuel efficiency and emissions," Chandra said. "The reductions in carbon emissions are therefore not great."*
"Our estimates indicate that two-thirds of people who buy hybrids were going to buy them anyway. So for the majority, rebates are not changing behaviour — they are subsidizing planned purchases."
And the higher the rebate, the more inefficient it becomes. "When B.C.'s rebate jumped from $1,000 to $2,000 in 2005, the actual cost of reducing carbon emissions more than doubled."