Tidal
Tidal Devices
Horizontal Axis Turbine
Vertical Axis Turbine
Archimedes Screw
Oscillating Hydrofoil
Enclosed Tips (Venturi)
Tidal Kite
There are other designs too.
The places that may benefit most from tidal and wave energy include:
Coastal Communities (especially isolated communities)
Islands
Island Resorts
This is because these types of locations tend to be highly dependent on diesel generators for power supply.
Tidal Technology
Tidal technology harnesses the highly predictable motion of daily tides. Well-placed tidal infrastructure can harness consistent energy between 18-22 hours each day.
Additional Components
Cables
Junction Box
These can have capacity for 10-50 devices, with one larger export cable that will then run along the seafloor. Towards land the cable must be buried to reduce impact on marine life.
Mooring & Anchoring System
"A mooring is a fixture to which a device may be secured. At sea there are many mooring methods that can be used to secure a device to the seabed. The main categories of moorings are identified below, however there are other options available – see Aquaret website for more details. The mooring and anchor examples provided have been used across the tidal, wave and floating wind industry."
Impacts on Marine Life
Marine Noise Pollution
Noise pollution can seriously impact marine organisms from plankton to marine mammals. Our oceans are constantly getting noisier, making it harder for species throughout the ocean food chain to survive. Most of the noise pollution is from shipping channels, but large construction projects are also a risk. In the case of tidal energy production, this may occur when devices and/or their anchors are placed on the seabed.
Bubble Curtains
Bubble curtains have been deployed in rivers and bays to help capture and direct debris (plastic pollution and invasive plant species) to collection points, but they've also been found to dampen noise pollution. In some cases they can entirely eliminate the harmful effects of noise pollution on some species, though they may only have limited protective qualities for others.
Testing Sites
Europe
UK
EMEC "EMEC’s clients benefit from a range of ready-made and cost-minimising test and demonstration facilities in major wave and tidal resources. Significant infrastructure investments have been made to make it as easy as possible for technology developers to learn by doing, with full confidentiality of performance data." Click here to learn more about their wave testing facilities.
Maps
Europe
UK
EMEC: Wave & Tidal Projects Interactive map "The RenewableUK ‘UK Marine Energy Database’ (UKMED) provides information about all known current and pipeline wave and tidal projects across the UK. Please note the locations of sites are approximate."
Companies
International
EMEC: Tidal Developers "a list of the tidal energy concepts known to EMEC. This list is alphabetical by company name and is not intended to infer any endorsement by EMEC of the concept or the companies concerned. The immature nature of the industry means that some of the categorisation of devices may not perfectly fit the simplified assessment made for this website."
Minestro's Deep Green "is the only known technology to operate cost-effectively at low-flow sites, generating electricity in stream flows as low as 1.2 m/s and can be installed both in shallow and deep water." "The ability to operate at low velocities makes Minesto's Deep Green the only technology to be cost-efficient in both tidal and ocean currents."
Nova Innovation "is a world-leading tidal energy company.
We design, build and operate tidal turbines that generate clean electricity from the natural ebb and flow of the tide."
