Abstract: The invention relates to a rack storage system comprising a storage rack (1) with storage shelves (12a, 12b) having storage spaces (17) for articles in rack stages (16) lying one above the other with a rack aisle (15) extending in between. Several guide tracks with first and second guide rails run along the rack aisle (15) (27, 28). First and second conveyor vehicles (3a, 3b) can be moved on the guide tracks, each of the conveyor vehicles (3a, 3b) having a drive motor (65a, 65b) and an electronic control unit (66a, 66b) and being controllable independently of one another. The first guide rail (27) is equipped with a first contact line arrangement (67) and the second guide rail (28) is equipped with a second contact line arrangement (68), each of the contact line arrangements (67, 68) comprising dedicated contact lines (69, 70).