Wave power is free, reliable, sustainable, renewable, and produces zero greenhouse gases and helps to reduce our carbon footprint.
Wave energy (or wave power), also called ocean wave energy, is the electrical power produced by harnessing the up and down motion of floating devices placed on the surface of the ocean. Ocean wave energy is typically produced by floating turbine platforms or buoys that rise and fall with the ocean currents.
Ocean waves contain tremendous energy potential. Wave power high-tech devices are designed to extract energy directly from the natural movements of ocean currents and the flow of motion to generate power. Wave energy can be generated by exploiting the changes in air pressure occurring in wave capture chambers that face the sea or changes in wave pressure on the ocean floor.
The concept to harness wave power is to form, guide or focus waves into a narrow channel to increase their size and power and to spin the turbines that generate electricity.
Wave energy is a type of renewable and green energy and is the largest estimated global resource form of ocean energy. Ocean wave energy is used for all different kinds of useful work, including electricity generation, propulsion for ocean vehicles, water desalination, and pumping of water.
P = wave energy flux per unit of wave-crest length
Hm0 = the significant wave height
Te = the wave energy period
ρ = the water density
g = the acceleration by gravity
* When the significant wave height is given in meters, and the wave period in seconds, the result is the wave power in kilowatts (kW) per meter of wave front length.
Wave energy converters (WECs)
WEC are devices that convert the kinetic and potential energy associated with a moving wave into electricity.
There are multiple methods and technologies invented and tested for capturing and converting wave energy to electricity are under development. These methods include placing devices on or just below the surface of the water and anchoring devices to the ocean floor. The five main types of technology commonly used including: Oscillation Water Columns (OWC), Buoys, Attenuators, Overtopping and Inverted-Pendulum.
Oscillation Water Columns (OWC) - a partially submerged enclosed structure. The upper part of the structure, above the water, is filled with air and incoming waves are funneled into the bottom part of the structure. When these waves come through the structure it causes the water column to rise and fall with the motion of the wave which causes the air in the top structure to pressurize and depressurize; this in turn pushing out and sucking back air through a connected air turbine at the top of the structure which in turn converting the energy into electricity.
Buoys - extract energy from the rise and fall and/or pushed side to side by the waves with a buoy. Once the energy is extracted it is then converted to electrical energy with a linear or rotary generator.
Attenuators (Terminators) - capture energy by placing floating structures perpendicular to the length of the wave; this causes the attenuator to contentiously flex where segments are connected. This connection is then drive a generator which convert the ocean wave to wave energy.
Overtopping - an offshore reservoir is created that has a wave lift over a barrier which fills a reservoir with water and is then flow back out through a hydro turbine that drives a generator. This technology is very similar to a conventional hydropower dam.
Inverted (Surface following) - Pendulum device uses the motion of waves to move hinged floating structures together back and forth. The motion of passing waves using the relative motion of the parts that drives electrical generators.
Same with any energy resources available, there are advantages as well as disadvantages of wave energy. However, the future of wave energy power is very bright. Since oceans cover 71% of the Earth, so it's very accessible. Solar always needs the sun, and wind energy always needs the wind to work. Since waves are essentially always in motion and are never interrupted, it's a reliable source compared to others.
This form of wave energy has an enormous global potential. With all the interests from governments to environmental groups and private companies growing among the masses regarding renewable and non-renewable resources, it is essential that everyone leans more towards the more sustainable resources of energy. Once this cycle begins, wave energy is bound to become a booming industry. It would also become the most sought after source of renewable energy. As its usage increases and it becomes more common, it can be expected that the costs will be normalized.
In the meantime, we need more funding and research to improve the technology involved and pushing prices down to a competitive level.