In a renewable energy age where there&rsquo;s increasing interest in sources of energy that are natural and environmentally friendly, sea water is also taking its place and becoming a natural source of energy for various high-tech uses. The amount of sea water available is vast; every one of the Earth&rsquo;s continents is surrounded by a cleaner, safer and more efficient answer to the planet&rsquo;s energy needs, according to Ocean Power Technologies, a New Jersey-based renewable energy firm specializing in wave power technology.
Perhaps the newest use for sea water is wave-power technology. Companies such as Ocean Power Technologies are using the power of the waves to create electricity. High-tech buoys bobbing up and down in the waves use that natural motion to produce electricity. The company is working on a wave-power project off the coast of Reedsport, Oregon, where one buoy in the water will begin making electricity by year&rsquo;s end 2010, according to Philip Pellegrino, vice president of business development for Ocean Power Technologies.
The company will add nine buoys to the project by year&rsquo;s end in 2011, according to Pellegrino. The company also has wave-power buoys off the coast of New Jersey and Hawaii. &ldquo;The technology is early stage and what we&rsquo;re doing is we&rsquo;re learning from demonstration efforts that we&rsquo;re doing throughout the world, and gradually improving on capacity and operability of the power buoys we&rsquo;re deploying,&rdquo; Pellegrino said.
Tidal and Marine Current Energy
The way sea water moves in the form of ocean currents and the tide coming in and going out is another source of energy. The best marine-current energy source in the U.S. is in the Gulf Coast around the tip of Florida, the U.S. Department of Energy (DOE) reports. The tidal energy in that area could potentially supply 35 percent of the electricity needs for the state of Florida, the department reports. These technologies are still being tested and, as of 2010, were in the prototype phase, according to the DOE.
Basically, these technologies use underwater turbines that are installed on the ocean&rsquo;s floor to catch currents in the same way wind turbines catch wind for electricity. There may be even more potential in sea water currents because ocean water is more than 800 times denser than the wind, the department reports.
Ocean Thermal Energy Conversion
Ocean thermal energy conversion is a process that uses heat stored in the ocean&rsquo;s sea water to generate electricity. Although it sounds high-tech, it isn&rsquo;t new. Origins of the process of turning the ocean&rsquo;s heat into power date back to the 1880s and the research came to the U.S. in the 1970s in Hawaii, according to the DOE.
Ocean thermal energy conversion works best when there is a temperature difference of 36 degrees Fahrenheit between the top layer of the ocean, which is warmer, and the deep, colder ocean water, the DOE reports. Ocean thermal energy conversion processes typically put warm surface sea water in pressurized containers, forcing it to boil and create steam that turns turbines and makes electricity.
- Philip Pellegrino; vice president of business development, Ocean Power Technologies; Pennington, New Jersey
- U.S. Department of Energy: Ocean Energy Technology Overview
- U.S. Department of Energy: Ocean Thermal Energy Conversion