Amid a fair amount of hype, a Virgin Airlines 747 has flown from London to Amsterdam using biofuels (BBC

| AP in USA Today | Bloomberg in the NYT). Not, when it comes down to it, very much biofuel – 20% of the fuel for one of the four engines, which sounds like 5% overall to me. And given that as far as I know Virgin doesn’t normally fly empty jumbos from Heathrow to Schipol, this ends up sounding like quite a lot of old-fashioned jet fuel being burned for no particularly good reason.

According to a rather breathless BBC backgrounder (“This short flight may prove to be a giant leap forward for the aviation industry” ) the biofuel used was sourced from coconut and babassu oil, an allegedly sustainable source but not one likely to be able to fuel all of Virgin’s fleet (none of the stories I’ve seen bother to say how big that fleet is, or what its biofuel needs might be). While the Virgin Green Fund has a biofuels company, Gevo, in its portfolio, this biofuel came from Imperium Renewables of Seattle, a concern that looks like it’s in a poor way according to the venture capital blog written by John Cook and hosted by the Post-Intelligencer (which I continue to believe has pretty much the best name of any newspaper ever).

Seattle interest is also explained by the fact that home-town team Boeing is involved (there was a nice post at Wired’s Autotopia on this at the time of the announcement); Virgin is running biofuel tests on a 747 with GE engines, and Air New Zealand is running them on jumbos with Rolls Royce engines. Why they’re doing tests on 747s rather than 777s (newer) or 737s (far more numerous) is unclear to me; maybe the risk of failure is high enough that you’d rather see it taken on one engine out of four, as in a 747, than one out of two? Meanwhile various sources note that Airbus has been experimenting with synthetic fuels, though not biofuels, in an A380.

There was at one time talk of doing the flight using biofuels not from oil crops but from algae – “snazzier scum-sourced juice”, as The Register puts it piquantly – but this didn’t transpire. Maybe in the future. We have a nice feature on next generation biofuels in this week’s Nature that will tell you more about Gevo, algae and a whole lot more. (And if you really want low emissions flight we also have a feature about the quixotic plans to circumnavigate the earth in a solar powered plane.)

Pretty much all of the stories include green spokespeople denouncing the flight as a stunt (which it clearly is). There’s a lot of green antipathy towards biofuels (much of it warranted) and towards flying, so the fact that the combination of the two goes down poorly is hardly a surprise. Personally I think it would be easier to offset aircraft emissions with direct capture of CO2 – yes, it’s expensive, but this is a high-cost sector of the economy. The fact that Branson has an interest in direct carbon capture might suggest that he, too, has had thoughts in this direction. (Damn; thought I’d get through the post without giving him a namecheck…Now that I’ve failed, let me at least direct you to the excellent New Yorker profile of him by Michael Specter – abstract only online, alas; 14 May last year if you have back issues lying around)