Oil crops are harvested for the valuable oil, and with the addition of alcohol, can be chemically converted to biodiesel, which consists of long chain alkyl esters. The process is relatively easy and yields a product that is usable in unmodified diesel engines. Problems from gelling (especially typical under cold temperatures) and contamination of water have occurred. For more information on biodiesel visit the National Biodiesel Board's website here.
Rapeseed is one of the most popular oil crops for biodiesel production because it produces more oil per unit of land than other conventional biodiesel feedstocks. However, due to the high cost of production of biodiesel because of planting, management, harvesting, and grinding of seeds, rapeseed may not be an economically feasible option. Canola is the most frequently used and recognizable cultivar of rapeseed and has a large market as a vegetable oil noted for it's high level of omega-6 and omega-3 fatty acids.
Soybean, a popular rotated crop in New York, can easily go from a cash crop to a biodiesel crop depending on the market and need of the farmer. Soybeans produce a high quality biodiesel, but yield lower oil per acre than other oil crops. New York farmers are familiar with their management which allows them to be easily integrated into the state's renewable energy plan.
The castor oil plants produce a seed which is 40 to 60 percent oil. Typically cultivated in tropical regions, the castor oil plant is not usually grown in New York. Research to investigate the adaptability of castor oil plants to the Northeast and the feasibility of their use as a bioenergy crop is being investigated at Cornell University's Agricultural Experiment Station in Geneva, NY.
Algae, aquatic photosynthetic organisms, can produce large amount of biomass. They specifically produce relatively high amounts of lipids which can be converted to biodiesel. These efficient microorganisms require little input or physical space, unlike typical oil seed crops. Algal biofuels are currently quite a hot topic and are being researched by many organizations around the world including Cornell University.
Other oil crops that are headlining popular press articles at the moment include jatropha and palm seed. These crops, like many others, are suited to a more tropical climate than New York state.