This chapter describes two forms of tidal energy generation, tidal range and tidal stream. Tidal lagoons work on the same principle as tidal barrages and have been proposed as a possible alternative. The main attraction to tidal lagoons is that they offer generation capacities similar to barrages but do not have the same environmental effects. Another method of capturing the energy from the tidal range is through a concept known as tidal delay which is an innovative idea being developed by Woodshed Technologies. In contrast to barrages and tidal lagoons, tidal stream turbines (TSTs) use the kinetic energy of the tide directly, and unlike the impoundment schemes, TSTs allow the water to pass through and around them and do not require the storage of water. The main categories into which most devices fall are horizontal‐axis tidal turbines (HATTs), vertical axis tidal turbines (VATTs), venturi effect devices and oscillating hydrofoils, though other novel designs such as ‘kites’ can be found.
This is a chapter from Wave and Tidal Energy.