I agree we need to reduce carbon emissions from all angles. And hopefully not wreck the economy in the process. I read both links and found the "drop in fuels" concept appealing. But not many details about what specifically drop in fuels are or how they are produced. I will do some looking around for more information. It would be awesome if you could pour something in your tank that would take the place of gasoline wthout the carbon footprint at a comparable cost. Almost sounds too good to be true. I think we have to be careful of solutions marketed as beig such that turn out to be rebranded petroleum. Pig with lipstick.