NOVELTY - A system for producing biodiesel (58) from algae (26) comprises: feed biomass source connected to depolymerizing reactor (32) configured for forming algal feed from biomass source; algae growth reservoirs (2, 6) including carbon dioxide source and mixing mechanism configured to circulate oil-producing algae within the reservoirs; algal feed separator (34) for directing a portion of feed to reservoirs; and oil extraction bioreactor (14) connected to reservoirs and configured for biologically rupturing algae cell bodies and oil vesicles of oil-producing algae to form algal oil and residue.    USE - As system for producing biodiesel and bioethanol from algae (claimed). The oil-producing algae include green algae such as Ankistrodesmus, Botryococcus, and Chlorella; blue-green algae such as Oscillatoria and Synechococcus and golden-brown algae such as Boekelovia.    ADVANTAGE - The system produces biodiesel from algae in a highly efficient and energy-positive manner, meaning the energy produced in the form of fuels is far in excess of external input energy, because very little fossil energy is used. Moreover, algae growth requires none of the heavy machinery, expensive fuels, or chemical fertilizers and pesticides required by conventional agriculture. Further, the algae can be processed near the growth ponds, eliminating transportation costs. The biodiesel produced by the system has the following advantages. The biodiesel formed is atmospherically carbon-neutral. In other words, all carbon released in combustion and/or fermentation was previously removed from the atmosphere during growth. Algal oil contains little or no sulfur, so production of biodiesel using the present system reduces sulfur emissions, even compared to ultra low sulfur petroleum diesel. Because of better combustion efficiency, biodiesel produces about 20% less carbon monoxide upon use by a consumer. Biodiesel burns more efficiently which results in a smoother-miming engine. The equivalent cetane number of biodiesel is higher than petroleum diesel, reducing diesel noise and knock. Biodiesel produces less soot, reducing particulate emissions by up to 75% and nearly eliminating the black smoke often associated with diesel engine exhausts. The alkyl esters or alkanes in biodiesel contain chains with none of the ring structures found in petroleum diesel. These petroleum ring structures or aromatic hydrocarbons give diesel fuel and diesel exhaust its characteristic smell. The smell of biodiesel fuel and biodiesel exhaust is cleaner and lacks most of the familiar diesel aroma. Biodiesel also has a higher flash point near 150 degrees C compared to petroleum diesel at 70 degrees C, so it is safer to store and handle. Biodiesel breaks down about four times faster in the environment, so spills are less enduring. Biodiesel has higher lubricity so fuel injection systems and other engine components can have a longer life. Further, the biodiesel can be mixed with petroleum diesels during the transition to 100% biodiesel fuels. Importantly, conventional diesel engines do not need to be modified to use biodiesel.    DETAILED DESCRIPTION - A system for producing biodiesel (58) from algae (26) comprises: a feed biomass source operatively connected to a depolymerizing reactor (32) configured for forming an algal feed from the feed biomass source; algae growth reservoirs (2, 6) including a carbon dioxide source and a mixing mechanism configured to circulate an oil-producing algae within the algae growth reservoirs; an algal feed separator (34) operatively connected to the depolymerizing reactor and the algae growth reservoirs, where the algal feed separator is configured for directing at least a portion of the algal feed to the algae growth reservoirs; and an oil extraction bioreactor (14) operatively connected to the algae growth reservoirs and configured for biologically rupturing algae cell bodies and algae oil vesicles of the oil-producing algae to form an algal oil and algal residue. The system further comprises a fermentation sub-system (40) for forming ethanol and/or ethyl acetate. The system comprises a nitrogen-fixing algae source (8) operatively connected to the algae growth reservoirs; a fermentation reactor operatively connected to the algal feed separator; a fermentation separator operatively connected to the fermentation reactor for separating a member selected from a carbon dioxide (CO2) product (46), an alcohol (36), an ethyl acetate product (38, 44), and/or a biomass residue (42); a CO2 recycle line operatively connected from the fermentation separator to the algae growth reservoirs; and a biological agent source (12) operatively connected to the oil extraction bioreactor.    DESCRIPTION OF DRAWING(S) - The figure shows a process flow diagram of a system for production of biofuels from algae.    Algae growth reservoirs (2,6)    Cultivation sub-system (10)    Oil extraction bioreactor (14)    Depolymerizing reactor (32)    Feed separator (34)