Wave energy is electricity produced by capturing the motion of ocean waves. Waves are created by wind blowing across the sea, often far from the coast, so they carry energy gathered over long distances. A wave energy converter turns their rise and fall, or their surge towards the shore, into mechanical movement that drives a generator.
Main device types
| Type | How it works |
|---|---|
| Point absorber | A floating buoy moves up and down against a fixed or heavy base |
| Attenuator | A long, jointed floating structure lies along the wave direction and flexes at its joints |
| Oscillating water column | Waves push air in and out of a chamber, spinning an air turbine |
| Oscillating wave surge converter | A hinged flap on the seabed rocks back and forth with the waves |
| Overtopping device | Waves spill into a raised basin and drain back through low-head turbines |
No single design has yet become standard, unlike the three-bladed wind turbine. Devices must survive storms many times stronger than the waves they normally work in, which is one reason costs remain high.
Wave versus tidal stream
The two are often grouped as marine energy but behave differently. Tidal stream turbines use currents driven by the moon and sun, which can be forecast years ahead. Waves depend on weather, so output can be forecast only days ahead, and it is usually stronger in winter. Wave devices work at or near the surface, while tidal stream turbines sit in fast channels.
UK status
The UK has a strong wave resource on its Atlantic-facing coasts, especially off western Scotland. Wave devices have been tested for two decades, mostly at the European Marine Energy Centre in Orkney, which has grid-connected wave test berths. Several early developers went out of business, and the Scottish Government’s Wave Energy Scotland programme now funds technology development. DESNZ reports wave and tidal stream together: 9.8 MW of capacity at the end of 2025, all of it in Scotland, generating about 16 GWh. There is no commercial wave farm operating in the UK.
Read more: Wave and tidal energy: how marine power works and where the UK stands.