Ocean Wave Technology

An emerging technology in green energy is harnessing ocean wave energy. There are a variety of technologies and approaches in various developmental stage throughout the world. In the US, Massachusetts has already incorporated marine and hydrokinetic options into their Renewable Standards Portfolio with other states soon to follow. The idea behind this is to find and develop ways to convert the mechanical and kinetic energy of water movement, specifically the motion of waves, into a source of electricity. According to Alternative Energy News, "energy output is determined by wave height, wave speed, wavelength, and water density." The agitation caused by and the oscillation of waves will some element in a device that will convert the mechanical energy into electricity via generators. These systems are designed to supplement the electricity needs of the large concentrations of people in coastal regions.

Ocean Power Technologies has developed a device called an Autonomous Power Buoy (APB). This system generates power by using the up and down movement of waves to drive a generator to produce electricity which is then transferred ashore via underwater power cables. One of the important design features is the capability of multiple buoys to be linked and networked to form a "power station" of various capacities according to needs. They are designed to support auxiliary functions such as serving as a platform for cell phone towers, a variety of vessel services (sonar, detection, and tracking), and research support. Working prototypes of this system are currently undergoing testing in offshore locations in Atlantic City (NJ), Oau (HI), and Santona (Spain), among others.

Pelamis Wave Power has also developed a system for harnessing wave energy. The Pelamis Wave Energy Converter is a "semi-submerged, articulated structure composed of cylindrical sections linked by hinged joints." The movement of waves is designed to move hydraulic devices in the couplings between the individual sections which, in turn, drive a generator. This device also transfers the electricity generated by underwater cable to onshore sites and distribution networks. The Wave Energy Converter does not have as many auxiliary uses as the OPT system does but it is also modular in the ability to adjust the number of cylinders as necessary.

Perhaps the greatest feature of this technology is that it has been determined to have minimal to no impact on the environment apart from visibility. An Environmental Assessment conducted by the Office of Naval Research, the OPT system was issued a designation of no significant impact (FONSI). This finding was supported by the National Marine Fisheries Service and the US Fish and Wildlife Services. Being that this technology is relatively new, cost of energy is a factor but further development and application will help mitigate this to levels that are very comparable to other methods for generating electricity. OPT estimates the cost of energy for its system to be approximately $o.15/kwh at a production level of 400 buoys. Another advantage of these systems is that they are designed to be self-sustained and require no operational input.

I am optimistic about ocean wave technology. It is an innovative way to harness another form of existing natural energy and has direct applications in providing alternative energy resources for the concentrations of people that reside in coastal communities throughout the world. The nature of this technology is to derive its electricity production from a source of energy that is, in itself, sustainable, with minimal environmental impact. An important fact is that there is no emissions. A concern that does occur to me is the potential for electromagnetic disturbances which may have unforeseen effects on the marine life that uses such properties for various functions. Still, wave energy bears far less consequences in the case of failure than, for example, oil pipelines and transportation by tanker. All in all, the scope of the benefits and deployment possibilities of wave energy technology inclines me to believe that this may be the wave of the future.