Abstract: A solar electric generator comprises a concentrator of the sun radiation consisting of a system of lenses which focalize the sun radiation into a vessel of which the bottom--that is the wall opposite to the radiation inlet--comprises a thermoionic stage, that is a high temperature electron emitter and a collector which are separated by a low pressure gaseous mixture. At thermal contact with the receiver of the thermoionic stage, a thermoelectric stage is provided, that is a plurality of couples of semiconductor material bars, one of the P type and the other of the N type. One of the ends of each couple is in contact with the collector of the thermoionic stage and the other end is in contact with a heat draining means for transferring the heat from the thermoelectric stage to the atmosphere.The electrical output from said two stages is taken out of the generator and suitably transformed to meet the user's requirement.