The present paper presents a very simple energy yield model fitted using the annual DNI and the latitude as main inputs, considering a solar tower CSP plant, with 100 MW of net energy output and 6 hours of thermal storage. Furthermore, a mask of suitable areas for CSP power tower installations in Chile is also shown. The mapping of solar radiation components has been calculated from multi-regressive models based on ground based measurements, existing maps of solar resources and atmospheric parameters. An analysis of the available data bases in Chile is also done in order to obtain useful information for the development of the work.