Wave and Tidal Energy:
Prospects for Use

Wave and tidal energy are promising renewable sources that can play a role in the global transition to sustainable energy systems. Oceans cover more than 70% of the Earth’s surface, offering enormous potential for clean energy generation.

Definitions and explanations

• Wave energy: This is the energy extracted from the movement of ocean waves caused by the wind. Waves contain a significant amount of kinetic energy, which can be converted into electrical energy using special devices.
• Tidal energy: Generated from the gravitational interaction of the Earth, Moon and Sun, resulting in regular tides. This energy is used to produce electricity through differences in water levels or the movement of tidal currents.

Technologies and mechanisms of work

Wave energy

1. Oscillating Water Column (OWC): A chamber with an opening below the water level where wave motion forces air through a turbine, generating electricity.
2. Point Absorbers: Floating devices that use the vertical motion of waves to operate a power take-off system such as hydraulic pumps.
3. Attenuators: Long, flexible structures positioned parallel to the waves that generate energy through movement along their length.

Tidal energy

1. Tidal Barriers: Dams built across estuaries or bays that use the difference in water levels between high and low tide to drive turbines.
2. Tidal current turbines: Underwater turbines similar to wind turbines but adapted to operate in water, which use the kinetic energy of tidal currents.

Current status

As of 2025, installed wave and tidal energy capacity remains limited compared to other renewable sources such as solar and wind. Major projects include:

• Sihwa Lake Tidal Power Station in South Korea with a capacity of 254 MW.
• Rance Tidal Power Station in France with a capacity of 240 MW.

In addition, there are numerous demonstration projects and test stations, such as the European Marine Energy Centre (EMEC) in Orkney, Scotland, which supports testing of devices in real marine conditions.

Recycling Prospects

A roadmap has been developed to achieve 300 GW of ocean energy by 2050, which includes wave and tidal energy. This target highlights their potential to:

• Creation of approximately 680,000 jobs.
• Contributing $340 billion in gross domestic product.
• Avoiding more than 500 million tons of carbon emissions.

This roadmap highlights the importance of wave and tidal energy to achieving global targets of net zero emissions and limiting global warming to 1.5°C, consistent with the goal of tripling installed renewable energy capacity by 2030.