The suitability of the Ag+↔Na+ ion exchange process was tested for the production of luminescent cover glasses with down-shifting properties suitable for solar cells. The photoluminescence properties were investigated as a function of the preparation parameters (i.e., Ag salt bath concentration, post-synthesis annealing temperature and duration). The performance of the samples was tested by measuring the output power of a Si solar cell covered with the treated glass slides and exposed to a solar simulator radiation; the photoluminescence quantum yield of the best performing samples was also estimated.