In this work, we studied the influence of the irradiation energy on the electric power of a monofacial solar cell in frequency dynamic regime under monochromatic illumination. After solving the minority charge carrier continuity equation in the presence of irradiation energy, we establish new expressions for the minority charge carrier density and electrical parameters such as photocurrent density, photovoltage and electrical power. Starting from these equations, we have represented the profiles of some electrical parameters such as the electrical power finally to highlight the effect of the irradiation energy on the latter.