This paper presents the first prototype of a new method, for assessing solar surface irradiance, benefiting from advanced products derived from recent Earth Observation missions. This method -called Heliosat-4- is based on the radiative transfer model libRadtran and will provide direct, diffuse components and spectral distribution of solar surface irradiance every 3 km and ¼ h over Europe and Africa. The advantage of the Heliosat-4 method is the simultaneous computation of direct and diffuse irradiances. The outcomes of this prototype of Heliosat-4 method are compared to ground measurements, of direct and global irradiances, made at 4 stations in Europe and Northern Africa. The results show that standard deviation attained by the Heliosat-4 method for global irradiance is fairly similar to that attained by current methods. A significant bias is actually observed and discussed.