At the current stage of unconventional energy sources development, we are looking for newer and newer materials with high application potential. One of the most dynamically developing technology that allows to recover lost thermal energy and convert it into useful electricity are thermoelectric generators. They use the phenomena taking place in thermoelectric materials with semiconductor properties. This project will be concerned research on the thermoelectric properties of high-centropic perovskite materials o general formula ABO3. So-called high-entropic oxides (HEOs - High Entropy Oxides) are a new group of materials consisting of such a large numer of elements occupying randomly one position in the crystal structure. It is then possible to stabilize them by configuration entropy. The key for this type of stabilization is to use a large number of cations (usually five or more) in equal molar amounts. This project will investigate the thermoelectric properties of a number of oxides perovskite highly centropic. This will be done in solid solutions of o formula (Ba, Sr) BO3, the number and type of cations will be modified in position B among the elements Zr, Ce, Hf, Ti, Sn, In, Y, Ho, Sm, Fe and Pr and the content of Sr and Ba. The measurements will concern the Seebeck coefficient S and thermal conductivity κ. In effect, the parameters such as thermoelectric power Pf and temperature thermocouple factor of merit ZT will be obtained. These measurements will be performed in conjunction with planned measurements of electrical conductivity. In the group of compounds mentioned above a large number of cations in one subnetwork causes disorder in the structure. This, in turn, may affect the lower ability to clustered defects and the value of migration entropy. In hence the low phonon component of the thermal conductivity combined with the relatively high electrical conductivity opens up the possibility of designing high-performance thermoelectrical materials.