A wind system for converting wind energy including at least one kite that can be driven from ground immersed in at least one wind current and a vertical-axis wind turbine placed at ground level. The wind turbine includes at least one arm connected through two ropes to the kite, the kite configured to be driven through the turbine to rotate the arm and convert wind energy into electric energy through at least one generator/motor system operating as a generator that co-operates with the turbine. The ropes are configured both to transmit mechanical energy from and to the kites, and to control the flight trajectory of the kites. A process produces electric energy through such a system.