Advantages
The use of underwater sails as an energy converter is a radically new solution for exploiting tidal streams. A tidal sail power plant uses a number of submerged sails affixed to cables, which span the tidal stream at a specific angle. The sails are moved by the tidal flow back and forth between two stations, driving a generator that produces electricity. Tidal sail power technology differs in a fundamental manner from any other proposed method of renewable electricity generation, and offers three basic key advantages compared to rotary converters:

- The effective catchment area of tidal currents per generator is determined by the total sail area exposed to the tidal flow and can therefore be made larger than that of a rotary system.

- The sails can span across any depth, as only the end stations moorings or mountings need to be fixed near the shore.

- The sails move slowly (at speeds less than the current) and horizontally, so that the mechanical stresses and friction are minimised.

These key features are rooted in the basic principles of the new technology and based on the underlying physics. Combined with its overall simplicity, they enable significant efficiency and cost advantages for sails over all other proposed solutions for capturing tidal stream energy. The power plants will be fully submerged installations, with no surface elements, and will be constructed in a modular fashion by combining several units (strings).