Oscillating Water Column — WEC design using trapped air pressure changes from rising/falling waves.

The Oscillating Water Column (OWC) is one of the most widely studied and developed types of wave energy converter. Its simplicity and lack of many moving parts in the water make it a robust and reliable option for marine renewable energy. The basic principle is straightforward: as a wave enters a partially submerged, hollow chamber, it causes the water level inside to rise and fall. This "oscillating" motion of the water acts like a piston, compressing and decompressing the air trapped above it.

How an OWC Works
The changing air pressure inside the chamber is channeled through a turbine. The air flow, which is bidirectional (as the water rises and falls), spins the turbine in a single direction, which is then connected to a generator to produce electricity. A key innovation in OWC technology is the use of a Wells turbine, which can rotate in the same direction regardless of the direction of the airflow. This simple but brilliant design eliminates the need for complex mechanical components to rectify the rotational motion.

Advantages of OWC
One of the main advantages of the Oscillating Water Column is its durability. Since most of the mechanical and electrical components are housed above the waterline, they are protected from the corrosive and powerful forces of the ocean. This can lead to lower maintenance costs and a longer operational lifespan. OWCs can be built as large, land-based structures integrated into coastal defenses or as smaller, offshore platforms.