Tidal Range

Types of Turbine

Andritz bulb turbine runner during installation

Bulb turbine

Andritz Hydro have produced bulb turbines similar to those used at Lake Sihwa tidal energy plant in 2011. The horizontal type of Kaplan machine - the Bulb turbine - shows extraordinary flexibility in its application. From small to large, from run-of-river to tidal, and from fixed to variable-speed everything is possible within a head range of 0.5 up to 30 meters.

Tidec's rotating turbine

Rotating Turret

Tidetec are developing a low-head turbine which is housed in a turret. The turret can be reversed after each tide so as to achieve maximum efficiency in each direction. They have the following benefits versus conventional turbines:

  • Optimal performance both ways (+30% production)
  • Low CAPEX (-20% investment)
  • High pump efficiency able to emulate natural tidal cycle in estuary
  • Lighter and more cost-effective
  • High fish friendliness
  • Low OPEX (-40% cost)
  • Flexible production allowing storage due to high discharge and pumping capacity

Potential UK sites

A map of the North Wales Costal Lagoon, with the region proposed for the turbines highlighted

North Wales Coastal Lagoon

The North Wales lagoon is being promoted by North Wales Tidal Energy and Coastal Protection as a potential site for tidal range turbines.

They propose 100 to 125, 8m diameter turbines fitted with 15 to 20 MW generators.

A map of Morecambe Bay, with the area suggested for turbines highlighted in red

Morecambe Bay

Morecambe Bay tidal barrage is being promoted by the Northern Tidal Power Gateways as another potential site for turbines. They are proposing to install 140 to 160, 8m diameter turbines fitted with 20 to 30 MW generators.

A map of Solway Firth, with the proposed area for turbines highlighted in red

Solway Firth

Several authors have investigated the power and impacts of the Solway Firth, proposing it as another potential site for tidal range turbines.