Energy can be extracted from the oceans in several ways, primarily through wave and tidal power technologies. Let's explore each of them:
Wave Energy: Wave energy conversion systems harness the kinetic energy from ocean waves. There are different types of wave energy converters, including:
a. Oscillating Water Column (OWC): OWC systems consist of a partially submerged chamber open to the sea. As waves enter the chamber, the water level rises and falls, causing the air inside to be compressed and decompressed. This oscillating airflow drives a turbine to generate electricity.
b. Point Absorbers: Point absorbers are buoy-like devices that float on the water's surface and move up and down with the waves. This motion is used to generate electricity through hydraulic systems or electromagnetic devices.
c. Overtopping Devices: These devices capture wave energy by using the rising and falling motion of the waves to fill a reservoir. The water in the reservoir is then released through turbines to generate power.
The energy extracted from ocean waves is usually converted into electricity. The generated electricity can be transmitted to the shore through underwater cables and integrated into the power grid for various uses.
Tidal Energy: Tidal power exploits the gravitational forces between the Earth, Moon, and Sun to generate electricity. Tidal energy can be harnessed through two main methods:
a. Tidal Barrages: A tidal barrage is a dam-like structure built across an estuary or bay. As the tide rises and falls, water flows through the barrage's turbines, generating electricity. Tidal barrages typically have gates that can be opened or closed to control the flow of water and electricity generation.
b. Tidal Turbines: Tidal turbines resemble underwater wind turbines and are placed in areas with strong tidal currents. The tidal currents cause the blades of the turbine to rotate, converting the kinetic energy of the moving water into electrical energy.
The electricity produced from tidal energy is transmitted to the grid for various applications, such as powering homes, businesses, and industries.
It's worth noting that ocean energy technologies are still evolving, and their deployment is relatively limited compared to other renewable energy sources. The energy generated from these systems is usually integrated into the existing power grid infrastructure, where it can be utilized locally or distributed to meet the energy demands of surrounding areas.