This week, the country’s leading thinkers on biodiesel are in San Francisco for the 2009 National Biodiesel Conference and Expo. Some of the highlights include:

One of the more cost effective places to grow biodiesel in the country could be the side of the road, according to Dallas Hanks from Utah State University. He heads up a project called Freeways to Fuel to study the feasibility of planting crops in the 30-foot wide shoulder next to roads.

The key is that the land would essentially be free. In the U.S. there are approximately 10 million acres lining 4 million miles of road that could be planted with oil seed crops, he said. There’s another 1 million acres alongside the 140,000 miles of railroad right-of-ways.

Algae was criticized by some attendees for requiring too much water. An expert at the show said algae could still be four to five years away.