it is possible to get energy from the ocean currents?

Question

we have been using the river flow for that,
the currents in the ocean are very strong, so I wonder if that exist or is is possible.
apologies for my english;)
Natalia

Answer 1

yes, it is being explored

Answer 2

All of the previous answers are very good, and I take nothing away as I add this, however, I am an operator in an electricity generating station, and know a little bit about this. The best generating would be done off of the continental shelfs, where water is literally 'dropping' thousands of feet. The same basic set-up as the generator in a hydro-electric dam would work great. The generator would be mounted on a barge, connected to a gear reducer which would be connected via a long drive shaft to an impeller turnned by the highly energetic ocean currents, thus turning the gear reducer (like a transmission in a car) that turns the generator which needs to turn at a specific rate. The problem then becomes transmission of high voltage current (138-765 thousand volts AC) under water to the nearest transmission substation. Water and electricity do not mix, and most transmission lines are bare conductors, no insulation to shield them from the water. Trunking lines together is a known ability, we have had underwater communications lines for about a century, but the amount of energy transmitted on those lines is orders of magnitude less than the amount that would be sent out across the lines you would need for this. Maintenance would also be highly problematic, salt water is corrosive, and also these water proof lines radiate heat, which would break down the insulation over time, causing the exact failure you would like to protect them from. Surface lines are really a bad idea, any ship that strayed into the path would destroy them, and it would be a security nightmare to protect them. Geothermal is probably the best bet, using underground heat to turn water to steam, and thus turn steam powered turbine-generators.

Answer 3

There is a conference on this coming up in 2007 in Hawaii. Also:

"The United States and other countries are pursuing ocean current energy, including Japan, China, and some European Union countries; however, marine current energy is at an early stage of development. There are no commercial grid-connected turbines currently operating; to date, only a small number of prototypes and demonstration units have been tested. Some of these technologies have been developed for use with tidal currents in near-shore environments; these near-shore tidal current energy technologies are not analyzed in the OCS Renewable Energy Programmatic EIS."

Check the links for more information.

Answer 4

It's possible to harness the flow of deep ocean currents, but it's difficult to achieve high energy densities, or ratio of power output to weight and size of the power plant, because the currents tend to be slow. When we harness rivers, we aren't actually harnessing the momentum of the water flow, but that we're harnessing the gravitional potential of the mass of the water, as it drops in elevation. That's why you see dams and hydroelectric power plants together.

An alternative way being investigated to harness power from ocean currents is a thermocline power plant, where the difference in temperatures between a cold, deep thermohaline and warm surface water is harnessed to run a power plant.

Both ideas have merit, but cost and efficiency are going to be challenges.

Answer 5

I suppose we could put big turbines anchored to the ocean floor, but it would be an engineering nightmare. Hideously expensive and probably not producing much power. And maintaining it, keeping it from getting rusty or barnacle encrusted, would be a never ending job. Protecting it from storm damage would be another problem. I bet the environmentalists wouldn't like giant turbines in the middle of the ocean either.

Answer 6

Yes, it is very possible !!!