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Tidal power provides predictable and secure generation capacity.  Research into a number of tidal range technologies and offshore hydropower is proceeding at a number of sites around the UK.  Tidal range energy is created by the difference in head between high and low tides. The barrage method involves building a barrier that traps water levels inside a basin, creating a tidal lagoon. The head is created when the water level outside of the lagoon changes relative to the water level inside and this is used to drive hydro turbines.  The massive potential carbon reduction savings and increased electricity generation, not to mention job creation and infrastructure improvements, that can arise as a result of developing such schemes cannot be ignored. The BHA supports and encourages the development of tidal power in the UK.
The BHA has published a booklet on tidal range energy – ‘TIDAL RANGE POWER – A future reliable renewable energy source’ which can be found at the foot of this page.

Offshore Hydro power

As the opportunities for large scale traditional hydropower applications in the UK are now very rare it seems sensible to look towards the sea to provide further opportunities. There is estimated to be around 6.5GW of marine energy capacity in the seas around Wales alone.

Tidal energy can be divided into 3 main categories:

·         Tidal Range

·         Tidal Stream

·         Wave

British Hydropower Association - tidal

Tidal range

Relies on the difference in head created by the tides, the high tide is stored behind a bund or lagoon wall and then released through turbines as the tide falls and electrical energy is produced. When the tide turns, water runs in the opposite direction powering the turbines once again. The cycle repeats day in day out. Cycles can be enhanced by pumping and the operation of sluices. Such schemes can offer improved coastal protection if coastally attached and can provide reliable and predictable large scale electrical energy for hundreds of years. The UK has particularly good tidal range 7-10m not being uncommon.

Tidal range brochure

If you would like a printed version, please contact Simon Hamlyn –  simon.hamlyn@british-hydro.org

Tidal stream

Utilises the flow of the tide.  Devices sit within the tidal flow and generate predictable electrical energy using rotors driven by the tidal flow. Often looking like undersea wind-turbines but shorter and stronger to withstand the greater forces within the sea. Devices typically require 3-6m flow speed although there are devices designed to run efficiently in less than 2m flow.

British Hydropower Association - marine


Less predicable than tidal range or tidal stream energy, as wave energy is a function of wind strength. These devices turn wave energy into electrical energy by harnessing the vertical component of the wave’s energy and converting to electrical energy either directly or by hydraulic means. Large scale deployment of wave devices may co-locate with floating wind plant many miles offshore.

Our Sponsoring Members

British Hydro Association – Representing the interests of the UK hydropower industry