To build an affordable photoelectrochromic energy conversion unit for self-powered smart window applications, the attractive multi-color Ag/V2O5 electrochromic counter electrode (CE) is coupled with a co-sensitized photoanode TiO2/CdS/PbS. V2O5 based devices are well-known for providing smart solutions when a voltage is applied but in this kind of configuration, the quantum dot sensitized solar cell (QDSC) drives the chromatic switching, with sunlight as the natural stimulus. The key objective in coating silver nanowires (AgNW) over the V2O5 film is to enhance the electrochromic as well as electrochemical performance of the device. AgNW impart good electrical conductivity to the layered V2O5 structure making it a promising CE and the transparency of the hybrid film in the visible-light region together with the plasmonic effect contributes to a better optical contrast. The PECD with Ag/V2O5 CE shows a transmission modulation (ΔT) of 31.1% with 45.8 cm2 C-1 coloration efficiency, which is significantly improved than with just V2O5. As compared to the liquid junction photoelectrochromic assembly, the individual films have a much higher ΔT (45.1% at 655 nm). The 5.21% power conversion efficiency (PCE) of the TiO2/CdS/PbS−S2−−Ag/V2O5 QDSC based PECD is a marked rise over that without both AgNW in the CE and PbS near infrared light harvesting QDs at the anode. This work attempts a detailed analysis of the photoelectrochromic and photovoltaic outputs of this novel PECD design with the hybrid film. Display omitted •Self-powered photoelectrochromic device of TiO2/CdS/PbS//Ag/V2O5 is demonstrated.•Highly conducting, plasmonic Ag nanowires enhance optical contrast of the PECD.•Improved electrocatalytic activity of Ag/V2O5 over V2O5 yields superior solar efficiency.•Reversible green to black switching under solar irradiance is demonstrated.•Competitive photocoloration efficiency (∼17%) achieved with low cost components.