Effective absorption and utilization of incident solar thermal energy in present basic solar collector is primary concern for energy efficient and optimum design due to heat absorption on surface and indirect transfer of heat to fluid medium. Poor absorption ability and transport properties of generally used conventional heat transfer fluid such as water, also limit the heat absorption and transfer efficiency of solar collector. Recently, Stable suspension of nanoparticles into conventional base-fluids has been used that improves the light absorption and thermo physical characteristics of the base-fluid which also results into an upside in the effectiveness of the solar collector. This novel fluid can be utilized for efficient absorption and heat transfer in solar collector. The present paper introduces the idea and design of Direct Absorption Solar Collector (DASC) and use of nano fluid as heat carrying fluid in order to experimentally analyse the developed DASC. The paper also discusses the experimental performance study on this new type of direct absorption solar collector for evaluating the effects of different Alumina nanoparticles concentration in Al2O3-water nanofluid used as a heat carrying fluid. Experimental instantaneous efficiency was calculated for three varying concentrations of Alumina nanoparticles, 10 ppm, 50 ppm and 100 ppm in actual outdoor condition. The results indicated the enhanced efficiency of DASC with Al2O3 nanofluid in comparison to base fluid water. The efficiency enhancement was 22.1%, 39.6% and 24.6% for 10 ppm, 50 ppm and 100 ppm concentration respectively. The promising results will provide potential development of nanofluid based DASC for efficient utilization of solar energy than a conventional solar collector © 2019 Elsevier Ltd.