A dual hybrid system, including an improved parabolic trough solar collector (CSP) and a biodiesel generator was designed and constructed in this study. The biodiesel was produced from 1st and 3rd generations of biofuel by means of the heat loss of CSP. In order to increase the efficiency of heat transfer of CSP with a working fluid, an optimization was performed with some nanoparticles in concentrate range of 1500-3500 ppm. The results showed that thermal conductivity coefficient of the fluid increased by enhancing the volume percentage. This led to an increase in the outlet temperature from the collector and caused better efficiency of CSP and therefore a better performance of the biodiesel transesterification reactor. However, the best working fluid was consisted of a water-based CuO nanofluid (efficiency of 66.42% and the rate of temperature of 1311.1 degrees C/min). Due to different outlet temperature, various experiments were conducted to produce fuel from rapeseed oil. The best efficiency results (74.54%) as well as the lowest finished costs (69 cents) occurred at temperature of 60 degrees C. Then, biodiesel was produced from chlorella oil at this temperature with an efficiency of 81.4% and total production cost of 143 c. (C) 2018 Published by Elsevier Ltd.