Chile presents a very suitable scenario for CSP technology, since the DNI exceeds 2000 kWh/m2/year [1] in more than half of the country, from the capital to the north. The objective of this study is to analyze the potential LCOE of solar tower power plants in Chile and to make a comparative site assessment for locations best suited for CSP in Chile. Additionally, also presents a novel method for scaling low accuracy weather data. For the techno-economic optimization, three sites at different latitudes are selected, for which a techno-economic optimization of the solar tower system is performed. The optimum thermal storage capacity is identified, together with two factors introduced in this study: the thermal multiple and the optical multiple. The results show that the introduction of the thermal and optical multiples provides a powerful method for comparative site assessment and plant predesign. The low LCOE obtained for the three locations (0.081-0.057 /kWh), yields a very favorable scenario for solar thermal plants in Chile, not only in the northern parts of the country, but also in regions close to Santiago.