Most Promising for Tidal

The Delta Stream Turbine
This turbine device was developed by Tidal Energy Ltd based in the UK. The 1.2 MW turbine consists of three, three bladed, horizontal axis tidal turbines each with a 15m diameter, mounted on a triangular frame to produce a low centre of gravity for stability.

Evopod Tidal Turbine
The Evopod Tidal Turbine was developed by Ocean Flow Energy Ltd. based in the UK. The device is a five-bladed, horizontal axis, floating structure which is moored to the seafloor. The mooring system allows the device to maintain optimum heading into the tidal stream. A 1/10th scale model is currently being tested in Strangford Lough in Northern Ireland (Ocean Flow Energy Ltd).

Free Flow Turbines
The Free Flow Turbine was developed by Verdant Power Ltd. based in the USA and Canada. This three-bladed horizontal-axis turbine has a diameter of 4.68 m and a prototype is being tested in New York City’s East River, generating 1 MW h of electricity per day. Late in 2008 Verdant Power Ltd. were awarded a $1.15 million contract from Sustainable Development Technology Canada to develop phase one of the Cornwall Ontario River Energy Project.

Stingray Tidal Energy Converter
The Stingray Tidal Energy Generator converts tidal energy through transforming kinetic energy from moving water into the hydraulic power.  It consists of a parallel linkage holding several large hydroplanes. The 150 kW prototype was successfully deployed in September 2002, in Yell Sound, off Shetland in the UK. However the device was removed several weeks later and development has stalled.

Lunar Energy Tidal Turbine
The Lunar Energy Tidal Turbine is a horizontal axis tidal current turbine and was developed by Lunar Energy Ltd. based in the UK. The technology is made up with a gravity base, a 1 MW bi-directional turbine 11.5 m in diameter, a duct of length 19.2 m and diameter 15 m, and a hydraulic motor and generator. The ducting is included to maximise the energy extraction from the current water flow. Lunar Energy Ltd. has recently agreed a £500 million deal to install 300 tidal current turbines off the coast of Korea.