"Lower carbon fuels, such as celluosic biofuels, could abate between 100 and 370 megatons of emissions, though this potential is highly dependent on innovation rates and near-term commercialisation of these technologies"
With the kicker about the US Auto industry that:
"Improved fuel efficiency could provide 240 to 290 megatons of abatement"
For me that is the key finding in Reducing Greenhouse gas emissions how much and at what cost, a new report from McKinsey & Company
Of course going along these routes is going to cost some people more than others, but then again, so is not following a route to reduce carbon emissions, McKinsey seems to be saying in its report.
The cost, by the way, seems to be around $50/ton if there are no automtotive fuel efficiency savings.