Current tidal lagoon designs capture energy directly from the tidal range via the lagoon’s turbine housing, limiting power generation windows to incoming and outgoing tides.
Water Powered Technologies’ Jetstream concept increases water transfer to and from the lagoon on both incoming and outgoing tides, resulting in higher differential generating heads and thus sustained power generating windows. This water transfer is carried out by a variation of our proven Venturo zero-energy pump technology. A large number of Venturos are attached to the periphery of the lagoon’s outer wall, which is a smooth, aerofoil shape. The pumps are operated by the increase in the water flow around the aerofoil shape which can be up to 25%.
On the incoming tide, the Venturo pumps operate to expel water from the lagoon and on the outgoing tide they pump water into the lagoon. Tidal water is prevented from flowing into and out of the lagoon by the bi-directional turbines' wicket gates. The turbine gates are opened at around high and low tide and closed at times inbetween. This ensures that the turbines start generating power at the maximum height differential which optimises efficiency and the power generation windows.
The lagoon is divided into two parts so that turbine maintenance can be carried out whilst still being able to generate power.
A tidal lagoon impoundment such as Jetstream provides the perfect location for a solar power array, where it is sheltered from aggressive waves and wind effects. Jetstream lagoons can utilise this haven to include the significant advantage of additional electric power generation from the sun via solar panels attached to floating pontoons. This can be used in several ways: to feed directly into the national grid; to power additional water pumps to enhance the Venturo pumps' capabilities, or to convert the sea water into its component gases. The conversion is achieved through the process of electrolysis where it can be stored on shore and either used as a direct fuel or recombined back into electricity via fuel cells for on-demand utilisation.