Haughtney - I am not denying the central role of new technologies (obviously these are critical) but my point is that technology alone will not fix everything. As energy consumers, we will need to modify our own attitudes and practices. So what is the answer? There is no single answer - it is like winning a world war; it needs the combined resources of everyone over a long and difficult period. The detail of jet fuel substitutes is but one of many highly complex technical aspects. The overall reduction of our fossil fuel addiction is a huge challenge. The good news is that at least these things are being seriously discussed in the mainsteam; unthinkable a few years ago. It is a start. Oh, and no need to make caustic remarks to someone just because their opinion differs from yours!