The CuFeO2 semiconductor, a delafossite compound with a lower band gap, has electronic and optical properties of interest for absorbing solar radiation in solar converters. In order to evaluate its potential the optical properties and their decomposition into atomic contributions are obtained using first-principles. Both ferromagnetic and antiferromagnetic spin alignments are considered. According to the results the structure, the Fe-Cu transitions makes almost no contribution to the absorption. Then, by using the absorption coefficient, the maximum absorption efficiencies, voltages, and currents of the solar conversion are found. The results indicate it as being a good candidate for solar cells but it does not generate enough output voltage for water-splitting.