AbstractIn this study, the effectiveness of electrospun poly(ethylene glycol) (PEG) nanofibers as polymer electrolytes for dye‐sensitized solar cells (DSSCs) is evaluated. Regular PEG nanofibers are electrospun at an applied voltage of 15 kV, using a polymer concentration of 13 wt% and tip‐to‐collector distance of 20 cm. Subsequently, the photovoltaic effect in DSSCs containing PEG‐nanofiber electrolytes with different I2 concentrations is analyzed. On reducing the concentration of I2 in the PEG‐nanofiber electrolyte, the short‐circuit photocurrent density (Jsc) of the corresponding DSSC increases significantly. A high power‐conversion efficiency of 5.93% is recorded (by a solar simulator under AM 1.5 illumination) for a PEG‐nanofiber‐based DSSC containing an I2/tetrabuthylammonium iodide (TBAI) molar ratio of 0.25. Additionally, electrochemical impedance spectroscopy is used to analyze the charge‐transfer resistance of the TiO2/PEG‐nanofiber electrolyte interface in the fabricated DSSCs; the electrolyte uptake, ionic conductivity, and charge‐transfer resistance values are investigated as a function of the molar ratio of I2/TBAI.