In recent years, considerable growth in demand for alternative energy sources justifies the investments made in the construction of wind farms, since wind energy appears to bring the least impact on the environment. Wind energy is generated from wind action, a source of renewable energy, totally clean and inexhaustible. Wind towers are built in huge parks with a defined distance between them. The higher the wind towers are, the better their performance, since we have the maximum use of the wind which is stronger and less turbulent at great heights. The materials used in the manufacture of wind towers are basically steel, reinforced concrete and prestressed concrete. The towers are usuallyin most cases, with circular or annular section. However, we should pay attention in a special way on the foundation of the wind tower, which should be designed and detailed to ensure the integrity of the structure as a whole. In this context, this dissertation aims to present the calculations required for the preliminary design or design verification of the foundation of wind turbines. Preliminary design and design evaluations were reviewed and evaluated to obtain a better understanding of the functioning of such structural elements. A spreadsheet was created using the Excel program, which performs the calculations of its foundation through analytical solutions. For the purpose of proving the accuracy of the worksheet results, some examples are presented and calculated from the created spreadsheet, and checked and compared to results obtained from an independent finite element analysis program. Stability and dynamics aspects of circular plates are also discussed.