Illustrative embodiments of systems and methods for powering lighted shelves in refrigerator appliances are described. In one embodiment, a refrigerator appliance may comprise a cabinet having a temperature-controlled compartment defined therein, a shelf ladder disposed at least partially in the temperature-controlled compartment and providing a plurality of shelf mounting positions, the shelf ladder comprising an electrical bus including first, second, and third conductors, the second conductor configured to supply power at a first current level when electrically coupled to the first conductor, the third conductor configured to supply power at a second current level when electrically coupled to the first conductor, and a first adjustable shelf carrying a first lighting device, the first adjustable shelf being removably mountable in one of the plurality of shelf mounting positions such that the first lighting device is electrically coupled between the first conductor and the second conductor.