Want to see the world's largest tidal turbine?

Question

Check out the pictures in the link below.

"A company called Marine Current Turbines will be installing a 1.2 megawatt tidal turbine in Northern Ireland's Strangford Lough in August. The SeaGen turbine will be the world’s largest ever tidal current device by a significant margin. It will generate clean electricity for approximately 1000 homes. The turbine is a prototype to be replicated on a large scale over the next few years. The rotors on the SeaGen turbine turn slowly: about 10 to 20 revolutions per minute. A ship's propellers, by comparison, typically run 10 times as fast. The risk of impact from SeaGen rotor blades is small, because the marine creatures that swim in strong currents tend to be agile, and can avoid slow-moving underwater obstructions."

http://www.treehugger.com/files/2007/06/12_megawatts_wo.php

Pretty cool eh?

gcnp - the blade tips are 16m in length, meaning they'll be travelling around 37 mph if it's doing 20 rpm.

I'm pretty sure the entire prop length is 16m (from the engineering company's website).

"16 m in diameter"

http://www.marineturbines.com/home.htm

The fish wouldn't have to swim 20 m/s, just in a direction perpendicular to the blades.

Your point about biofouling is taken though.

Answer 1

This is fantastic !!!

Oceanic currents are more than sufficient to produce the energy we consume worldwide.

Answer 2

You realize that if that thing really goes 20 RPM the blade tips are going around 80 MPH through the water? Talk about a huge underwater Cuisinart. Imagine the scene when that turbine encounters a huge jellyfish bloom like the one that killed all the salmon. Biofouling will probably also be an issue. Most marine engineers I know are fairly critical of these things for that reason.

See here for instance:

http://democrats.science.house.gov/Media/File/Commdocs/hearings/2007/energy/17may/o'neill_testimony.pdf

Biofouling issues are related to a one-word mention, which belies the critical importance. Because they are nearly intractible, the industry downplays the risk. Here are some of the technical issues:

http://books.google.com/books?id=foYoke66OpgC&pg=PA159&lpg=PA159&dq=biofouling+ocean+power+generation&source=web&ots=h-HGAXcnda&sig=4OKLyaIXbXkLpqGkriF5MJsEUyU

My point is not that this is a bad idea, it's just that it's not going to be easy to generate significant amounts of energy cheaply or easily using ocean energy generating systems. Space is a much more benign environment to work in than the ocean. You can make a satellite work for years with no maintenance in space, unattended buoys in the ocean, even in benign environments like the equatorial Pacific need to be serviced fairly frequently.

Edit: I know this seems harsh, but until everyone, even people who firmly and correctly believe something should be done to reduce carbon emissions, starts arguing from scientifically sound and technically feasible positions nothing of any significance will happen. It does no good to waste vast sums of money of undersea power generation technologies if the prospects of these things will be to get coated with barnacles, microbial mats, and whale entrails and fail in less than a year. We might as well join in a circle and sing Kumbaya. If we are really going to get serious about this, and I do believe we have to, we need to do things that will make a difference. Based on what I know about the issue of biofouling and what I have seen happen to things that get put in the ocean, it is not clear to me that ocean energy generation makes sense from an engineering standpoint. Now if you want to argue that question, I am up for it, but we all need to be able to face hard truths or we won't get anywhere.

Edit2: 20 m prop length, diameter = 40 m,
circumference = pi*diameter = 120 m, approximately,

Rotation rate equals 20 RPM = 0.3 Hz.

Rotation rate times circumference equals linear speed:
120 m * 0.3 1/s = 40 m/s.

Conversion between m/s and knots is roughly a factor of 2, so about 80 mph. The tips are cooking.

Edit: Got the rotor diameter wrong. Oh well. 40 mph is still fast, not many fish swim at 20 m/s. Anyway, the main objection is biofouling.

Answer 3

Scottish Power Renewables is building the world's first commercial scale tidal array in the Sound of Islay, situated between the Scottish islands of Islay and Jura.Estimated to cost £40m, the tidal array is expected to see the beginning of preparatory works in 2012 and installation of the tidal machines between 2013 and 2015.

Answer 4

It always amazes me how positive information brought to this forum can be trashed without offering any better alternatives, short of staying our current course and building more nukes.

Thanks for sharing this info...

It goes to show how one side of the debate is constantly thinking about new ideas and ways to make the future better. While the other side delays, tries to confuse, and will continue to obstruct progress towards a potentially better future for everyone.

Answer 5

Thats some bigazz prop there. Now all they need to do is install 999 more just like it to equal the output of a typical nuke plant.

Answer 6

Iran is usual with of that as quickly as oil runs out or it fairly is replaced by option varieties of capability, this would spell disaster for his or her economic equipment. with the aid of fact the Seventies, Iran has been actively attempting to discover different sources of capability and economic develop to fend off in comparison inevitable destiny. Iran, by the 80s and 90s had a scarcity of electric powered era. people who sat by blackouts understand this nicely. The nuclear potential plant will help Iran in this feeling and could additionally enable Iran to sell extra of its electrical energy to neighboring international places such as Afghanistan. be conscious that Iran at present powers the electrical powered energy for Afghans and US forces in Western Afghanistan. to boot, Iran has been attempting to get closer commercial countries in technologies for an prolonged time. They opt to have the comparable technologies with the aid of fact the main modern-day states. they opt to have the understanding and adventure on those new technologies in basic terms like all different united states of america. additionally, be conscious that international places such as Russia and US have oil reserves rivaling that of Iran. yet they have stepped forward nuclear potential plant life with the aid of fact they have many advantages. Nuclear potential plant life are plenty extra fee effective to function than oil based plant life. the disadvantage is the threat from them exploding!. they are additionally plenty air purifier than oil based potential plant life.

Answer 7

Pretty cool.
How often do they have to scrape the barnacles off of it?

Answer 8

ya that could play h## with a fishing net or an anchor line alright

Answer 9

Cool. I just got an email from a friend who'd be interested in this. Thanks!

Answer 10

wow, pretty cool.