The electrical properties of an n(+)-p-p(+) structure-based single-crystalline silicon solar cell were studied by impedance spectroscopy, I-V and spectral response. The impedance spectrum is measured in dark, under different intensities (14, 43, 57, 71, 86, 100mW/cm(2)) of illumination and wavelengths (400-1050nm) of light. Under dark and at low intensities of illumination (<50 mW/cm(2)) the impedance spectra show perfect semicircles but at high intensities the semicircles are distorted at low frequencies. It is found that illumination provides an additional virtual R(1)C(1) network parallel to the initial bulk R(p)C(p) network observed under dark conditions. The value of virtual resistance R(1) depends on the illumination wavelength and shows an inverse relationship with the spectral response of the device. (C) 2009 Elsevier B.V. All rights reserved.