Simple geography: Switzerland is landlocked. It has no coastline, no ocean access, and no tides.
Tidal barrages require a large tidal range (difference between high/low tide) in an estuary or bay connected to the ocean. Switzerland's waters are lakes (Geneva, Constance, Maggiore) and rivers (Rhine, Rhône, Aare, Ticino)—all freshwater, non-tidal.
Swiss Renewable Focus Instead: Hydropower (60%+ of electricity) from alpine dams/run-of-river, solar, wind (growing), geothermal (exploring). World-class pumped storage (e.g., Nant de Drance). Tidal is physically impossible.