Tidal power: how it works

[kfcfan20]

i luv porn

[heckicare]

Thanks for posting this, this will help with my project. May I use this vid? (I'm just gonna use it anyways LOL)

[bjack1317]

energy rox

[olson11m]

I think that this looks like a good way 2 make green energy. i will be using this in my science project, so it sounds good 2 me. :) our world should b tottaly green someday

[03Fay]

For a science project, I have to show the process of how tidal harness works. Do you mind if I draw out a similar drawing to how you display the turbines?

[lamtengchoy]

see new invention

[Beermonkeybob]

Is there any posibility of using Wind, Tidal and wave power all on the same offshore sites as then they could share the same transmition systems and also limit the geographical impact by utilising the same site?

[suedonym0]

maintenance. what happens when barnacles, sea snails, seaweed and all kinds of slime grow on it and gum up the works? Some kind of bladder system must work better. 

[goldcheerleader2010]

this is an amazing animation. i am using it as homework, it is really simle and easy to understand. Fabulous!!

[Twep08]

I think this plant isn't as efficient as it could be, because the trubines powered by the water movement are rotating in two different directions. So maybe during half of the time the charge will be neutral , so no electricity.... Maybe theres a better way of using the tide .Something like storing the water for a short time...

Becaus we have to use indeed renewable energy sources.

[MrMoneyeyez]

How come you don't advertise this video? It's cool to make a video, but NOT to advertise this video to people who can make these machines, thus creating jobs for you and your friends is just WRONG! ADVERTISE THIS VIDEO!

[PUNKDUDE1991]

wuju...all you can eat sushi bar...xD....this is bad people i rather have OTEC than this huge blades underwater...poor nemo...lol

[AmberStar209]

i think this isnt the only way to use tidal power

[shigeno389]

but water waves has inconsistent direction.. how about that?

[Oniobo]

the turbines can only be places in the mouths of bays and estuaries, and would be blocked by the entrances of the power stations, they would be not slaughtering of and whales.

[curingaging00]

but tidle power is still in it's infancy and i believe it will advance alot in a few decades.

[tahoeskiier]

just imagine all the whales and fish those spinning blades will kill. Reminds me of the birds that are slaughtered everyday in california from windmills. Poor whales do not stand a chance with these turbines and the japanese chasing them

[curingaging00]

I think theres a way to construct a net metal chamber that will allow alot of water to flow through, but not allow fish to go through.

theres however a problem with the seaweed.

[swunt10]

@tahoeskiier

wow. either you are realy stupit or you are a sarcasm genius... anyway thx

[Sikringsskap]

0:05

[jmvneto51]

My project uses old platforms as base for many generators but it can be on land too. It uses old technology and nothing that does not suppose to be close to the water is in the water. Marine environment is hard on anything that stays in the water for long time. Barnacles are like pest, add weight and can stop any moving part dead on. Take a look on my video: ocean power, wave power, wind turbines, sun power, (ocean power, the blue power (3rd edition))

[RubbishIdeas]

good idea

[zelda2geek]

ok its a good video but when you pause it for to long and then play it the hole thing goes by really fast i mean fast!!!!!!!!!!!!!!!!!! but it helped me alot in my science project thanks alot.

[zelda2geek]

the world is changing so much im happy about it

[dangermackie]

If you look at any man made structure in the sea, you've got to consider a few points.

One is the corrosive nature of seawater. For instance phone dropped in sink -dry it out phone works fine. Phone in sea water, circuits dissolve - phone never works again.

If you put a mesh in the water, i can gaurantee you within a day it will be covered in seaweed. Sea weed build up would block the flow of the water.

[dangermackie]

Also when you discuss why haven't people done it yet you've got to understand tidal energy is only in it's infancy. The tidal and wave devices that Greenpeace show in it's videos are only two possible designs that are in the process of being developed.

The above design has been built and is the biggest tidal turbine in the world. MCT are the company that built it. As far as i'm aware they have someone on watch 24 hours on the device, who turns the blades off when a seal is spotted.

[neilandfi]

The Severn Estuary is a nursery for many fish species. It is also THE major point of entry to the inland waterways of southern Britain,esp eels, salmon, and shad. I don't know the exact figures for the percentage of the tide that will actually generate power, but it is suggested that the turbines will be raised somewhat to allow for siltation, which will naturally diminish that figure. It is also accepted that the presence of the barrage will reduce tidal range to some extent. Pure guess 20%loss

[neilandfi]

The great shame of it is, during the time it has taken for this enquiry by the govt, tidal stream turbines have taken a great developmental leap way past the potential of any barrage.

[alexkvaskov]

Could anyone tell what percent of the total energy of the tide do these generators actually get?

[ostepopps]

Could someone tell me how the gearbox works, and about tidel power in the future. How will it be, is it good for the enviroment and so. Thanks for all replies ! :)

[DataWizard223300]

The point I'd really like to raise is:

Why not evaluate a barrage design with

(a) Offshore wind turbines on top and/or beside the barrage?

and

(b) Provision for tidal stream turbines in the vicinity of the sluices where the barrage would amplify the inrush tide?

[DataWizard223300]

The large barrage proposal is equivalent to 3 nuclear power stations or 15,000 wind turbines.

I think the comment by GreenPeaceUK ("[this technology] can be considered to have a similar cost to [offshore] wind") is an underestimate. However, if we accept it as a ball park figure, then a large barrage costing £20 billion (?) is comparable (arguably better) than the equivalent of 15,000 wind turbines which would cost about £30 billion.

[DataWizard223300]

This type of turbine captures a substantial slice (but by no means all) of the Kinetic ("moving") Energy of the water. They do so on both the ebb and flow tide. However these designs do not capture as much of the Potential ("lift") Energy as would a barrage.

I do not think the people proposing the Severn Barage are "idiots" they are aware of this technology.

[neilandfi]

They are certainly aware of it, but they are competitors, so they're hardly going to support it. I think that people are missing the point with tidal barrages: there is only one entirely successful project in the world, which is La Rance. Barrages CAN work in situations like that: low (or no)silt environments. But even so, they will reduce the tidal range, so they don't tap all the power of the tide, only that part which remains after their construction, and after siltation effects.

[GreenpeaceUK]

Two points AASteveo:

1)We already have hundreds of cables carrying electrical charges under the sea - they are insulated from the water using inert materials.

2) sea water itself actually carries a weak electrical charge which sea animals deal with quite easily.

So no need to worry, basically...

[boxa888]

EVERYONE GOOGLE"INCREASING HUMAN ENERGY"BY NIKOLA TESLA!he gives all of the energy resources that you can use without ruining the environment and how to build them! he wrote this article for people who care like you greenpeace! this was 100 yrs ago! the wireless power tower sends a form or radiowave that allows for industrial running of machinery and emits no pollution!please i put up a ton of information to show that it works, i also demonstrate a 20 ft wireless transmission with a small model!

[p3x197]

@AASteveo There not gonna put live wires in the sea are they that have not been insulated

[EnricoSuarve]

Do you have any figures on the output vs costs (installation and operational) from this type of installation or examples already in place?

Surely this type of thing would be relatively simple to install alongside existing offshore windfarms which presumably have roughly the same sort of geographical requirements?

[GreenpeaceUK]

Tidal stream technology is still in its infancy and therefore there are no comparable projects at the present time. The cost of utilising tidal streams will be very site specific and depend on the technology used. The turbine or other generating plant equipment can be considered to have a similar cost to wind.

Once installed, electricity will be produced with no fuel costs and will be completely predictable. Maintenance costs will be the main costs during the life of the project.

[bristolsurfer]

Maybe you can tell the idiots who want to build the severn barrage about this?

Good work.

[gmodesike]

sushi-maker!

[DataWizard223300]

Not so, apparently. Although the scale of the machinery is large, the speed of rotation is relatively slow. Statistically most fish should get through...similar to the way birds and bats (for the most part) avoid wind turbines.

[gmodesike]

good point

[neilandfi]

Again I disagree with you Datawizard..in part anyway. Migratory fish often hang around in estuaries for considerable periods of time, and may pass through turbines a number of times before continuing their journey. At Annapolis Royal Barrage in the Bay of Fundy, they have had quite a bit of slicing and dicing going on with fish attempting to pass through the turbines. But I believe more research is required here to ascertain just how much of a problem it is.

[neilandfi]

It is also worth pointing out that larger species will have a greater difficulty and greater danger when attempting to pass through turbines...which they will certainly attempt. Seals, dolphins and other cetaceans are frequently observed well inland of proposed sites for any barrage. I hasten to add that they are not lost. This is part of their normal hunting range.

Tidal stream turbines are now available that can operate in shallow waters, and they do not present such a big threat.

[KN0MAAD]

I can't see why they don't just make big cages around them. If this is a problem have they thought about it? Or what about getting two big round discs slicing one from radius to circumference jaming it through the other one making it somewhat like a "Whirlybird".

[gmodesike]

lol! you said "ascertain"

pretentious are you!?

it is a law that people who use the word "ascertain" are pretentious

:)

love

g

[neilandfi]

You shoot defenceless pumpkins.. nuff said!

lol

[gmodesike]

:) that i do!

[alexkvaskov]

Put a mesh covering onto the turbine - the water passes, the fish can't. But one thing though - where will the fish breed, feed etc

[HolySpringRolls]

I dont think they would allow mesh. there are already too many problems with lost fish nets in the sea. baby fish get caught and cant grow to reproduce.

[nowellian]

Renewable energy sources are unlimited!

No Nukes!

[DataWizard223300]

Unfortunately Nowellian, you are only partly right when you say "Renewable Sources are unlimited!"

They may be very, very abundant and dwarf human sources of energy, but that does not necessarily make them "economically accessible".

60% Carbon reduction by 2050 probably means having Onshore Wind, Offshore Wind, Tidal Stream, Tidal Barrage and Nuclear.

[nowellian]

DataWizard - Onshore Wind, Offshore Wind, Tidal Stream, Tidal Barrage and Solar!

The risks associated with nuclear not to mention the unsurmountable radioactive waste storage problems make nuclear an unacceptable alternative. Not to mention nuclear power is not cost effective, it takes massive government subsidies. Those massive government subsidies should go to solar not nuclear.

[poomacintosh]

i have it in my ppt presentation

[cross0fire]

i saw the "efficenCity". it was amazing :) I'm going to use this video and the wave power plant video for my presentation in school. thanks

[iiEMMA]

woow, that was very helpful im planning to show it to my class during my presentation on renewable energy

:D

thanks

[GreenpeaceUK]

Glad it was useful, iiEMMA. You can find lots more info about renewables and energy for the 21st century at greenpeace org uk/efficencity

(our virtual town with links to real-world examples).

[agathagw]

yeah, it's useful, thx!

[SlashSkull]

Thanks For the info! ;)

[GreenpeaceUK]

Glad you found it useful, SlashSkull.