Among the renewable energy sources currently available, photovoltaic energy is considered one of the energy sources with the greatest capacity for growth in the short and medium term. This great growth potential is due to the operation and composition of photovoltaic panels composed of photosensitive semiconductors, which when in contact with solar radiation generate electricity thanks to the photoelectric effect. Carrying out a detailed analysis of efficiency and energy quality in a photovoltaic system is vital to achieve a correct assessment of the feasibility in the technical and economic aspects. It is for this reason that the main objective of this research work is to present an analysis of the efficiency and energy quality of three photovoltaic systems, through the decay function, which allows simulation of the performance of a photovoltaic system over time, taking into account maintenance problems. Non-optimal operating conditions and the effects that pollution can have at the time of energy generation in the photovoltaic panel, the correct analysis of the data obtained, in addition to a correct implementation of a maintenance plan, translates into an increase in energy production, significantly improving the energy production of the panel by 15% thus, maintaining optimal energy quality levels, presenting a distinguishing factor of less than 5%, in addition to improving the efficiency of the system by 8%.