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Thermoelectricity, which is the direct conversion of heat into electricity, is the term that indicates the physical phenomena resulting from the motion of charge-carriers under the action of temperature gradient [1]. The electronic properties of the layered BaFAgCh (Ch = S, Se, Te) were investigated using the full potential linearized augmented plane wave (FP-LAPW) method [2] as implemented in the Wien2K code [3] with the TB-mBJ [4] functional to model the exchange-correlation potential. The FP-LAPW band structure and the semi-classical Boltzmann transport theory were used to study the charge-carrier concentration and temperature dependences of the thermoelectric parameters, including Seebeck coefficient, electrical conductivity, thermal conductivity and figure of merit [5].  The potential of the BaFAgCh (Ch = S, Se and Te) compounds as thermoelectric materials in the carrier concentration range 1x10¹⁶ - 1x10²⁰ cm^-3 was assessed . The obtained results show that the values of the thermoelectric parameters for the p-type compounds are larger than that of the n-type ones. Seebeck coefficient value along the c-axis is found to be higher than its value in the ab-plan. However, electrical conductivity (σ), electronic thermal conductivity () and figure of merit (ZT) are found to be higher in the ab-plan. This can be  attributed to the fact that the charge carrier effective masses along the c-axis are larger than those in the ab-plan. The optimal charge carrier concentrations and temperatures that yield the maximum values of the figure of merit for the title compounds were calculated.