NOVELTY - The method comprises producing electric-power in an oxyfuel power plant by combustion of a fuel with oxygen to obtain carbon dioxide, obtaining the oxygen from algae cultivation, feeding the obtained carbon dioxide to the algae cultivation, harvesting algae and obtaining algae oil and algae mass, fermenting the algae mass to ethanol and remaining algae mass, refining the algae oil and the ethanol to biofuel, processing the remaining algae mass to fish fodder, farming fish, feeding the fish with the fish fodder, and recovering sediments from the fish farm.    USE - The method is useful for combined generation of electric power and biofuel from algae mass, where the biofuel and electric power are useful in car and aircrafts.    ADVANTAGE - The method allows economic and easy generation of electric power and biofuel from algae mass with less energy consumption and high yield.    DETAILED DESCRIPTION - The method comprises producing electric-power in an oxyfuel power plant by combustion of a fuel with oxygen to obtain carbon dioxide, obtaining the oxygen from algae cultivation, feeding the obtained carbon dioxide to the algae cultivation, harvesting algae and obtaining algae oil and algae mass, fermenting the algae mass to ethanol and remaining algae mass, refining the algae oil and the ethanol to biofuel, processing the remaining algae mass to fish fodder, farming fish, feeding the fish with the fish fodder, recovering sediments from the fish farm, recovering nutrient salts from the sediments, adding the nutrient salts to the algae cultivation, obtaining water produced from the combustion of fuel, adding the produced water to the algae cultivation and additional carbon dioxide to the algae cultivation, obtaining nitrogen rich water from the fish farm, and adding the water to the algae cultivation. The method further comprises compressing the oxygen from the algae cultivation together with recycled exhaust prior to the combustion. The combusted fuel is biofuel. The additional carbon dioxide is obtained from an external process. An INDEPENDENT CLAIM is included for an energy production system.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic view of an oxy-algae, power and food producing system.