We need a massive gasoline tax and we need rebates for early adopters of new technology. Why? Well, we need stable gasoline prices so that manufacturers know that demand for high fuel economy cars will be there and it's a safe business bet to pour resources into them. We also need expensive gasoline to get the single-passenger SUV commuter vehicle to die. The fact that Canada has fewer for them than the US shows that higher gasoline prices work.
Rebates for EV's can work, but they need to be well thought out. Just saying "EV" is not the way to do it. It needs to be for vehicles that can show a certain full-stream emissions and energy consumption below a certain point. Remember the rebates for Hummers in the US? We don't need some version of that happening.