why can't we harness energy from ocean waves?

Answer 1

We can (see below), but attempts to harness the energy from waves have failed because they require large structures over large areas and these structures should be capable of surviving storm conditions with energies hundreds of times larger than they were designed to capture.

Water waves can store or dissipate much energy. Like other waves (alternating electric currents, e.g.), a wave's energy is proportional to the square of its height (potential). Thus a 3m high wave has 3x3=9 times more energy than a 1m high wave. When fine-weather waves of about 1m height pound on the beach, they dissipate an average of 10kW (ten one-bar heaters) per metre of beach or the power of a small car at full throttle, every five metres. (Ref Douglas L Inman in Oceanography, the last frontier, 1974).

In addition, surface waves are limited by the density of water and the pull of gravity. They can travel only along the surface and their wave lengths can at most be about twice the average depth of the ocean (2 x 4 km). The fastest surface waves observed, are those caused by tsunamis. Note that tsunamis reach their minimum at about 6000 km distance. Beyond that, the curvature of the Earth bends the wave fronts to focus them again at a distance of about 12,000 km, where they can still cause considerable damage.

Answer 2

These are a few good links wherein u can get some stuff reg how energy is being generated from oceans.....

it is possible n also being already done in many places in europe....
so far the best source of energy from the ocean is TIDAL ENERGY.
There r many plants generating energy from the tides in many parts of Europe,North America n Japan in Asia..(if i'm not wrong)
The other sources are OTEC (Ocean Thermal Energy Conversion), Ocean Current Energy , n more....

The Only thing that matters here is the efficiency part of it... It is very less efficient to operate a tidal energy plant..... So naturally the cost goes up...
Also to install waterproof equipment is another problem... the equipment is getting corroded due to the high salinity factor of the ocean water.... So due to this also the Cost factor is very high... So it is not recommended for conventional purposes n only at special places where it is felt necessary n good for extracting the energy, it is recommended........

Hope my answer satisfies You........

Answer 3

Ocean waves present power in completely random packets, not smooth flows. These packets get large enough that nothing can withstand them - thousands of years of engineering boats show that you need to go with the water,not oppose it. Extracting energy means that you have to oppose the wave force. In addition to trying to extract from a random and potentially unopposable force, you're doing it in the worst engineering environment on earth - highest ambient energy, most erosion, salty and wet so most corrosion, and subject to biofouling on all surfaces that aren't continually scrubbed. Producing energy reliably and cheaply under such conditions- and then getting it to shore reliably - is a severe engineering challenge.

Answer 4

no other reasons other than it is still under development, it requires large investment in money and facilities,most people think that it's not cost effective and you'll lose a lot of your beaches and good surfing areas.
so it's not a question of can't but a question of won't.
actually and other potential source of energy from the sea would be to tap the temperature differences the surface of the oceans and the bottom of the seas.
God bless,
gabe

Answer 5

It is Done, But not very useful as other kind of energy source. Because is depend on the waves.

Answer 6

Truly it's because of politics and money.Governments would rather buy weapons invest in military rather than searching for clean fuels.The worst is that we have the sea as a reservoir of water,there are technologies that transform sea wwater into drinlable water but the technology is said to be 'expensive' but for the same governments its aint expensive to buy trillions of dollars of killing machines.

Answer 7

there are existing ocean wave power plants. however, the location must be strategic, meaning that the ocean must be particularly having strong but consistent currents.

Answer 8

Even though waves can hold a lot of energy they are not frequent enough or reliable enough to supply a neat form of energy.You can use it to break rocks though.

Answer 9

We can. It's done:
http://www.worldchanging.com/archives/000445.html
http://tyler.blogware.com/blog/_archives/2005/10/7
http://www.engin.umich.edu/dept/name/research/projects/wave_device/wave_device.html
http://www.worldenergy.org/wec-geis/publications/reports/ser/wave/wave.asp
http://64.233.183.104/search?q=cache:xVZpGNgR-x4J:www.nsf.gov/pubs/1998/int9815/ssr9809.doc+OWC+wave-energy+conversion+system&hl=nl&gl=nl&ct=clnk&cd=1
http://64.233.183.104/search?q=cache:w6t3Mqxyg8EJ:www.otti.de/pdf/guenther/coe2580.pdf+france+%22ocean+wave+energy%22&hl=nl&gl=nl&ct=clnk&cd=1
It's still under development, but it's already being used a little, and in the long run it probably will be a good and stable source of energy.
Together with other substitutes ('normal' hydro, solar, wind, earth heat, biomass, fusion, etc.) we hardly or not need the rather polluting oil / fission in the future.

Answer 10

I have heard of this, and it is feasible. My guess why it's not done is that it's cheaper to build nuclear power plants.

I think congratulations are in order that Heinz has made it to level 7.