Here's a tidbit to tuck under the hat: Biodiesel and renewable diesel aren't the same thing. Here's a note from Solazyme, the algae fuel makers:

"The molecules in biodiesel are primarily FAMEs (fatty acid methyl ester), usually obtained by transesterification. Renewable diesel is hydrocracked and refined, and is nearly molecularly indistinguishable from standard diesel that comes out of the pump. Also, ASTM does recognize the difference. Solazyme’s biodiesel meets ASTM D6751 specs, whereas the renewable diesel meets ASTM D975 specs."

So there you have it. (Transesterification, by the way, is the process of removing esters from oil. It's what the guys who make biodiesel out of drippings from the deep fat fryer at Long John Silver's do.) Solazyme, by the way, won a second contract from the Navy this week, this time to deliver 1,500 gallons of jet fuel made from algae. Earlier, the company signed a contract to deliver 20,000 gallons of renewable diesel to the Navy. It's also making a soy milk substitute from algae.

On other algae notes: Parc is experimenting with a chamber that might be able to easily separate algae from water. De-watering is one of the big problems for most algae companies (except Solazyme, which has a dry algae process).