In this paper, thermal performance of a flat-plate volumetric solar collector using a blended plasmonic nanofluid as its heat transfer fluid was investigated. The blended plasmonic nanofluid used in the experiment was manufactured based on three different aspect ratios of gold nanorods (AuNRs), and it was designed to have broad-band absorption over the visible and near-infrared spectrum. The conversion process of solar radiation to heat in the blended plasmonic nanofluid was verified experimentally by measuring the temperature distribution inside the nanofluid under illumination of a tungsten halogen lamp and by comparing it with the simulation result. Through the theoretical investigation of a flat-plate volumetric solar collector, effects of channel depth, channel length, mass flow rate, and the magnitude absorption coefficient of the blended plasmonic nanofluid were characterized in order to establish a basic design. The results of this study will facilitate the development of highly efficient solar thermal collectors using plasmonic nanofluids. (C) 2016 Elsevier Ltd. All rights reserved