Most bio-diesel is currently being made from food crops.
That’s bad. Using edible fats to power vehicles just makes no sense to me. You can’t feed petroleum or coal to people, so let’s reserve the food crops for feeding people and animals, eh ?
What gets me about the whole electric vehicle and plug-in hybrid vehicle vs. CTL is that nobody ever questions the ultimate end point. You can’t fly fighter jets, bombers, or even passenger jets on electricity yet, but you could on CTL. Not sure about bio-diesel in jets, but I don’t like the idea of burning edibles anyway.
It doesn't have to be that way. 70% of Earth's sun absorbing surface is unused saltwater. Most people don't know this but all the energy in petroleum originally comes from saltwater algae. With bioengineering it should be possible to create super-algae that can be converted efficiently into bio-diesel and alcohol fuels. It's a bit silly to consider but the oceans are so vast we could breed whales to eat the algae/plankton mix then swim their oily selves to the coasts for conversion to fuel. Most of our transportation fuel use is near the coasts. The good thing about making our own petroleum is it would create a CO2 closed loop system allowing nearly unlimited economic expansion. Saltwater algae or some kind of saltwater plant seems to me to be the most promising direction.
About plug-in hybrids: why not embed electric lines in the road beds of highly traveled freeways and use induction to transfer the power? The hybrids then would not need heavy batteries which would noticeably increase mileage. When the car brakes it could sell the power back to the grid. These cars could be hooked up into virtual trains boosting freeway lane capacity by 10. We'd get all the benefits of commuter trains with the personal freedom of automobiles.