Solar electric vehicle (SEV) is an emerging transport utility, which primarily uses solar energy for its propulsion. It is regarded as an ideal solution for clean and sustainable transportation. This article presents an approach to investigate the reliability and availability of a SEV facilitated with a standby plug-in option. A composite reliability model is developed in Markov framework incorporating the stochastic failure and repair characteristics of all critical electrical systems of the vehicle, namely, power supply system, energy storage system, motor-drive system, controllers, and energy management system. A new probabilistic index is proposed to determine the availability of power generated by the photovoltaic modules mounted on the SEV. This index can be treated as a useful parameter for designing area-specific reliable SEV models. The reliability improvement due to the standby plug-in facility is also examined. The study quantitatively justifies that a SEV with a plug-in facility is much more reliable and effective than a regular plug-in EV. The article also illustrates some novel concepts which can support further research on new reliability design and maintenance of a SEV.List of Symbols and Abbreviations: G, Solar irradiation; G std , Standard solar irradiation; G ref , Reference solar irradiation; T max , Maximum temperature; T min , Minimum temperature; α, Temp. coefficient of PV arrays; P max , PVG capacity; P mup , minimum useful power; r sw , reliability of the changeover switch; R PVG , Reliability of the PVG; A PVG , Availability of the PVG; λ PVS , FR of the PVS; μ PVS , RR of the PVS; λ PVG , FR of the PVG; N i , No. of SEV at i th CS; U i , interruption time per year at i th CS; λ c , FR of the converter system; μ c , RR of the converter system; R CS , Reliability of the CS; A CS , Availability of the CS; λ CS , EFR of the CS; R PSS , Reliability of the power supply system; r SW , Reliability of the change-over switch; Q, truncated matrix; λ 1 , discharging rate of battery; μ 1 , charging rate of battery; λ B , EFR of the battery; μ B , ERR of the battery; A B , Availability of the battery; λ CC , EFR of the charge controller; μ CC , ERR of charge controller; A CC , Availability of charge controller; A ESS , Availability of the ESS; λ ESS , EFR of the ESS; μ ESS ,