A set of equipment for generating electric energy for vehicles equipped with a chassis and tyres preferably intended to power a cooling unit of the vehicle, which comprises: - at least one generator assembly, - a battery, - a control unit connected to the battery, wherein the at least one generator assembly comprises: - an axle and a wheel arranged on one of the ends of the axle, wherein the wheel is intended to make contact with the upper portion of one of the tyres of the vehicle such that when the vehicle moves it causes a rotational movement of the wheel and therefore of the axle; - an electric generator connected to the axle which transforms the rotational energy of said axle into electricity, and attached to the control unit and the battery in order to store the electricity generated by the rotation of the axle; characterized in that the at least one generator assembly further comprises: - a drive mechanism, configured to move the wheel between a resting position wherein it is separated from the tyre, and a working position wherein it is in contact with the tyre, such that it is kept in the working position until the electric generator is at 100% charge and the wheel moves back to the resting position, wherein the drive mechanism comprises: - a support intended to be linked to the chassis of the vehicle, - a movable plate attached to the support, - a cover supporting the electric generator, and which is in contact with the movable plate, - a drive element, attached to the movable plate, so as to move the movable plate with respect to the support, integrally with the cover and the wheel, from the resting position to the working position, and - a solenoid valve, connected to the control unit, which enables the passage or exit of pressurised air to the drive element. - at least one generator assembly, - a battery, - a control unit connected to the battery, - an axle and a wheel arranged on one of the ends of the axle, wherein the wheel is intended to make contact with the upper portion of one of the tyres of the vehicle such that when the vehicle moves it causes a rotational movement of the wheel and therefore of the axle; - an electric generator connected to the axle which transforms the rotational energy of said axle into electricity, and attached to the control unit and the battery in order to store the electricity generated by the rotation of the axle; - a drive mechanism, configured to move the wheel between a resting position wherein it is separated from the tyre, and a working position wherein it is in contact with the tyre, such that it is kept in the working position until the electric generator is at 100% charge and the wheel moves back to the resting position, wherein the drive mechanism comprises: - a support intended to be linked to the chassis of the vehicle, - a movable plate attached to the support, - a cover supporting the electric generator, and which is in contact with the movable plate, - a drive element, attached to the movable plate, so as to move the movable plate with respect to the support, integrally with the cover and the wheel, from the resting position to the working position, and - a solenoid valve, connected to the control unit, which enables the passage or exit of pressurised air to the drive element. - a support intended to be linked to the chassis of the vehicle, - a movable plate attached to the support, - a cover supporting the electric generator, and which is in contact with the movable plate, - a drive element, attached to the movable plate, so as to move the movable plate with respect to the support, integrally with the cover and the wheel, from the resting position to the working position, and - a solenoid valve, connected to the control unit, which enables the passage or exit of pressurised air to the drive element.