Chris, I'm pretty sure that the last time the world was at this stage of the cycle, taxes hadn't been invented.
The idea in Tom's link above of using algal bioreactors is nothing new. Some friends from my reseach days helped set up a company in Sussex that was using similar technology but went bust a few years ago.
The algae can be grown in conditions that produce amounts of useable oil, but because of their temperature requirements it's uneconomic in our climate. The alternative is to grow them in med/tropical climates but then the transport costs make it uneconomical and the idea of increasing national fuel security is lost.