Devices for Harnessing Wave Energy
Wave energy harnessing technologies convert the kinetic and potential energy of ocean waves into electricity. There are four main types of devices:
1. Terminator Devices:
- Orientation: Perpendicular to the wave direction.
- Mechanism: These devices have a stationary part and a moving part that moves up and down like a piston in response to waves. This movement pressurizes air or oil, driving a turbine to generate electricity.
- Example: Oscillating Water Column (OWC) converter.
- Power Rating: Typically ranges from 500 kW to 2 MW, depending on wave parameters and device dimensions.
2. Attenuator Devices:
- Orientation: Parallel to the wave direction.
- Mechanism: Long, multi-segment floating structures connected by hinges, which extract energy as the waves move along their length. The segments are connected to hydraulic pumps or converters to generate power.
- Example: Pelamis wave energy converter.
3. Point Absorbers:
- Orientation: Not specific; absorbs energy from waves coming from any direction.
- Mechanism: A floating structure with parts moving relative to each other due to wave action. It utilizes the rise and fall of wave height at a single point, driving a turbine generator system to produce electricity.
- Example: AquaBuOY WEC.
4. Overtopping Devices:
- Mechanism: These devices have reservoirs that are filled by incoming waves, creating a slight build-up of water pressure. The stored water is released back into the ocean through turbines, generating electricity.
- Example: Salter Duck WEC.