Aquamarine Power's Oyster wave power technology captures energy in nearshore waves and converts it into clean sustainable electricity. Essentially Oyster is a wave-powered pump which pushes high pressure water to drive an onshore hydro-electric turbine. Wave power is generated by wind blowing over the surface of the ocean far out at sea. The action of the wind transmits energy into waves. These waves can travel vast distances with little energy loss before breaking on the shore. Our Oyster device is designed to harness this energy and convert it into electricity.
Mechanical offshore device
The Oyster wave power device is a buoyant, hinged flap which is attached to the seabed at depths of between 10 and 15 metres, around half a kilometre from the shore. This location is often referred to as the nearshore.
Onshore electricity generation
Oyster's hinged flap, which is almost entirely underwater, pitches backwards and forwards in the nearshore waves. The movement of the flap drives two hydraulic pistons which push high pressure water onshore via a subsea pipeline to drive a conventional hydro-electric turbine.
In the future, subsea pipelines will connect multiple Oyster wave energy devices to a single onshore plant. Ultimately Oyster will be installed in wave farms of several hundred connected devices generating hundreds of megawatts of electricity.
By locating Oyster in the nearshore, we are able to capture a high proportion of the energy available in the ocean whilst avoiding the severe storms which occur further out to sea.
- Mechanical offshore device
- Minimal underwater moving parts
- No control system, gearbox or shut-down mode
- No complex offshore electronics
- Hinged flap ducks under largest waves
- Nearshore location
- Robust offshore structure
- Operates even in storm conditions
Shore-based electricity generation
- Keeps electricity out of the water
- Minimal ecological impact on marine environment
- Easy to access
- Reliable proven hydro-electric plant
Ocean waves represent our planet's last untapped natural renewable energy resource. Over 70 per cent of the earth's surface is covered with water. The energy contained within waves has the potential to produce up to 80,000TWh of electricity per year - sufficient to meet our global energy demand five times over. The potential to capture energy from the sea offers a vast and endless source of clean sustainable electricity.
Predictable by nature
Ocean waves are generated by wind passing over the surface of the sea - a process which often begins many hundreds or thousands of miles from shore. Because waves originate a long way from shore, computer models of wave propagation allow us to accurately forecast incoming waves up to five days in advance.
In comparison with wind energy, it's easier to accurately predict how much energy can be generated by waves, and when. In addition, the peaks and troughs of wind and wave energy do not always coincide. This means there are times when there is abundant wave energy and little wind. This diversity helps even out the fluctuating nature of some renewable energy sources. When combined with other renewable energy, such as hydro power, it helps provide a more predictable and steady renewable energy mix.
A diverse renewable energy portfolio means a more stable energy system, reduced variability and lower cost. In addition, a strong renewable energy mix means we become less reliant on traditional power sources such as oil and gas. This gives us greater energy security.
Minimal environmental impact
Wave energy is, by its nature, a clean energy resource. Aside from the energy expended in manufacture and installation of wave energy devices, it produces no carbon emissions. Our industry is still very new but studies undertaken to date show the process of capturing wave energy has minimal environmental impact. Our Oyster device, for example, is a simple, slow-moving buoyant flap. This flap moves backwards and forwards in the waves and pumps water ashore. There is no electricity production or fast moving equipment at sea. And as Oyster uses freshwater as its hydraulic fluid it means there are no hydrocarbons in its system. The device sits largely underwater so there is minimal visual impact.
There is an obvious link between wave energy and desalination - the process of removing salt from water to produce freshwater. There are a number of island groups, such as the Canary Islands, which receive little rain or have limited means to capture and store rainfall. Instead seawater must be desalinated by a technique known as reverse osmosis. Energy fuelled by diesel generators is used to pump high pressure saltwater over special membranes to produce freshwater.
Our Oyster device offers a cleaner, more cost-effective solution. Oyster could be configured to produce high pressure saltwater direct to a desalination plant, without the need for fossil fuels whatsoever.