Tidal Lagoons
Tidal Lagoons Tidal lagoon is a new and promising idea to exploit the energy in tides by building one or more lagoons in shallow water and generating electricity by means of turbines from the flow of tidal water into each lagoon when the tide rises and then out again when the tide falls. Offshore tidal lagoon power generation resolves the environmental and economic problems of the barrage system and puts tidal power generation back amongst the choices for commercial-scale renewable power generation. Rather than blocking an estuary with a barrage, offshore tidal power generators use an impoundment structure, making it completely self-contained and independent of the shoreline. It is similar to having a circular dam, built on the seabed. The concept of a tidal lagoon is not a recent proposition. As of 2009, no tidal lagoon has ever been built anywhere in the world, and although the technologies used would themselves be classed as mature, the concept itself is currently unproven due to a number of remaining uncertainties over design, construction methods and physical impacts.
Tidal Lagoons
Source: mng.org.uk
An advantage of this kind of renewable power is that it is entirely predictable. And if three lagoons are built together, computerised management of the turbines can ensure continuous generation of electricity.
Possible disadvantages include the effect of a tidal lagoon on local currents and consequent erosion of the shoreline, and possible damage from quarrying if rock is needed to supplement material from the sea bed that is used to build each lagoon.
Tidal Electric Ltd estimate that the Unit price (for 1 kWhr) would be in the range 2.0 - 2.5 pence. This compares very favourably with the price estimates in the Government's Performance and Innovation Unit report 2002 which studied a range of renewable, fossil fuel and nuclear technologies
