•The proposed method is simple, inexpensive and suitable for small PV systems.•The photodiodes are useful to detect partial shading and irradiance changes.•Whole-year MPPT simulations have been conducted to evaluate every method.•The PV model can calculate the output curves under complex shading patterns.•The proposed method overcomes the standard ones regardless the climatic conditions. Maximum Power Point Tracking (MPPT) is needed in a photovoltaic system to ensure the operation in the Maximum Power Point (MPP), maximizing the generated energy. Many MPPT techniques have been developed. Perturbation and observation, as well as incremental conductance, are by far the most widely used because of their simplicity. However, they have some weak points and problems that affect their efficiency, especially under rapid irradiance changes and partial shading. This paper proposes a novel MPPT method which can be implemented in PV (photovoltaic) inverters and charge controllers. The most innovative feature is the presence of photodiodes as irradiance sensors. Thanks to irradiance measurement, the proposed method can recognize problematic scenarios and execute specific algorithms to prevent malfunction under these situations. The MPPT method has been theoretically analyzed; efficiency results are shown in comparison with standard techniques, which verify its feasibility.