| With water encompassing over 70 percent of the | | | | An open-cycle uses the ocean's warm surface |
| Earth, it would make sense to try and gain alternative | | | | temperature to make energy. Warm seawater boils |
| energy from the ocean. Ocean Thermal Energy | | | | when placed in a low-pressure container. The steam |
| Conversion or OTEC is a way to do just that. French | | | | turns the low-pressure turbine, which in turns moves |
| engineer Jacques D'Arsonval is the brainchild of the | | | | the generator. It is condensed back into liquid form |
| idea. In 1881, he felt that the thermal energy of the | | | | when it comes in contact with cold temperatures from |
| ocean would be able to provide a great, clean source | | | | the cold seawater. |
| of energy. In other words, the different temperatures | | | | A hybrid-cycle contains features of both systems. In |
| of the ocean in deep and shallow waters will be able | | | | the hybrid system, warm water is flash vaporized |
| to run a heat engine, which runs efficiently with great | | | | causing the steam to vaporize the low-boiling point fluid. |
| temperature changes. | | | | The vapors drive the turbine and the steam |
| There are three states that are heavily involved in | | | | condenses with the cold temperature creating |
| exploring OTEC. The United States is one of them and | | | | desalinated water. |
| has a large OTEC facility in Hawaii. Tests are done | | | | While it sounds like a great plan and a wonderful way |
| here to learn more about the technology. It has been | | | | to use the environment in a safe manner, the problem |
| said to be the perfect place for OTEC because of the | | | | is this technology is extremely expensive. The United |
| warm surface temperature and access to deep cold | | | | States hasn't run any new tests in almost 10 years |
| temperatures of the ocean. Japan, while not a great | | | | because of the costs, especially with companies |
| area for OTEC, created a closed-cycle OTEC plant | | | | focusing on other energy sources. Few other countries |
| on the island of Nauru. It uses the energy to power the | | | | have been working at ways to find an operational |
| plant and neighboring communities. India also sponsors | | | | system. The reason why it is so expensive is because |
| OTEC operations and is looking for ways to get new | | | | the main thing needed is a large pipe, sometimes a mile |
| and better energy. | | | | long to reach to the bottom of the ocean to get the |
| There are three ways to use OTEC: open cycle, | | | | cold water. Creating this pipe and maintaining the |
| closed cycle and hybrid cycle. Of the three cycles | | | | process costs too great of a price. |
| there are also three locations, land-based, shelf-based | | | | However one of the huge advantages to OTEC is |
| and floating-based. | | | | that it provides more than just electricity. By bringing up |
| A closed-cycle system uses a fluid with a low boiling | | | | the cold water from the bottom of the ocean, there |
| point to rotate a turbine. Warm surface ocean water is | | | | are many other uses such as air conditioning, chill-soiled |
| pumped in causing the fluid to evaporate and the | | | | agriculture, desalination and mineral extractions. But |
| vapor turns the generator. Cold ocean water is | | | | there are concerns worldwide about the effects of |
| pumped through the other side, causing the substance | | | | using alternative energy from the ocean can cause on |
| to form back into liquid and start the cycle all over | | | | the environment. Unfortunately, because of the lack of |
| again. | | | | research this question may never get answered. |