Across California, University of California scientists are studying potential biofuel crops. Putnam has four research trials under way, testing varieties from Ceres and Mendel Biotechnology, Inc.  He said switchgrass and miscanthus the top contenders so far in his trials.

“The yields of switchgrass under irrigation have been quite high,” Putnam said. “It is an efficient crop for converting solar energy into biomass under warm weather condition.”

Switchgrass does have relatively high water needs. Putnam said scientists are looking into whether the crop can be grown under deficit irrigation to save water and still produce the biomass.

“The key issue with biofuels is not necessarily the total water requirement, but the water use efficiency and amount of biomass produced per unit of water,” Putnam said. “Even if a crop has high water use, if it produces a large amount of biomass, it may still be the best option.”

Steve Kaffka and UC Cooperative Extension advisors are involved in research on winter annual oilseeds such as canola, camelina and meadowfoam as potential biofuel feedstock crops.

“Recent economic modeling we have done suggests that at current market prices, canola is a competitive crop in California, but outlets have not yet developed for the seed,” Kaffka said. “Currently, petroleum prices are too low to support the use of canola for biofuel feedstocks, but that is changing rapidly. “

The director of the UC Kearney Research and Extension Center, Jeff Dahlberg, sees opportunities for California production of sorghum as a biofuel crop.

"Sorghum is one of the few crops that span all the different renewable fuel options," he said. "You can use the grain to convert into ethanol. We have sweet sorghum, a specialty sorghum which is very similar to sugar cane. You can press the juice out and convert it into ethanol. And, we can produce a lot of biomass."

Dahlberg previously served as research director for the National Sorghum Producers and the research director for the United Sorghum Checkoff Program in Lubbock, Texas. He currently is lead investigator on a $984,000 U.S. Department of Energy grant to study the composition of sorghum and its potential for cellulosic conversion to biofuel. In addition to continuing this research at Kearney, Dahlberg is interested in developing a center for on-farm green technologies at the Central California research station.