Underwater Seafloor Turbines

[botsapper]

Set aside the huge Texas oil reserve finds, restarting 'clean coal', Elon's slick solar roofs and Trump banning wind mills by his Scottish golf course; North America's first tidal turbine generator has gone online. The famous Bay of Fundy, Nova Scotia will harness the power from the high and low tide movements to generate 2 MW of electrical power, adding more turbines to produce 300MW target by 2020. The two-cycle tide height differential of 56 feet involves 160 billion tons of water. The cycles will be harnessed by seafloor tidal turbines, 50 ft dia turbines weighing 1,000 tons. It also has the least environmental impact to marine life and natural ecosystems.

https://www.youtube.com/watch?v=e-gVA6JpbrU

[freebeard]

Moon Power!

The Fundy Standard | Fundy Force

Tidal devices operating in here endure tides moving at speeds up to 5 metres per second, rising up to 16 metres vertically, and expanding up to 5 kilometres horizontally. During peak flows, turbines will experience forces similar to a class 4 hurricane – under the water.

[jamesqf]

Originally Posted by freebeard

Moon Power!

And how long do you suppose it will be before the hard-of-thinking start whining about how it's going to bring the moon crashing down on Earth?

[oil pan 4]

The tidal cycle there is a little more on the very extreme end.
So it won't work that well everywhere.
On the bright side there will be more power for the tar sands extraction project.

[freebeard]

https://en.wikipedia.org/wiki/Tidal_acceleration

The average tidal bulge is synchronized with the Moon's orbit, and Earth rotates under this tidal bulge in just over a day. However, Earth's rotation drags the position of the tidal bulge ahead of the position directly under the Moon. As a consequence, there exists a substantial amount of mass in the bulge that is offset from the line through the centers of Earth and the Moon. Because of this offset, a portion of the gravitational pull between Earth's tidal bulges and the Moon is not perpendicular to the Earth–Moon line, i.e. there exists a torque between Earth and the Moon. This boosts the Moon in its orbit, and slows the rotation of Earth.

Tides boost the Moon upward and slow the Earf's rotation.

oil pan 4 -- For low-head situations you'd want ocillating water colums:

https://www.google.com/search?q=oscillating+water+column

They use a 0-pitch low efficiency rotor that works whether the water is rising or falling. OTOH using Moon power to grub in the ground for smelly tar seems negatively efficient. Maybe better to use it to make electrochromic glass for retro-fitting sky scrapers.

[MetroMPG]

I had been following this story a little bit.

They also made a tidal-fed basin in the bay which captures water at flood tide, then closes the opening at slack water. Then they feed the flow back through a conventional hydroelectric turbine set-up.

Apparently they capture the occasional whale in the basin too.

(After which point there is a big sale on sushimi at the local grocery store?)

[oil pan 4]

Whale is actually pretty good.

[freebeard]

With that mass of water to work with you could use a [gang of] hydraulic ram[s] to raise large quantities of water above the high tide mark, and reap added energy on output.

[chefdave]

Hi in scotland in the pentland firth. They have just built the uk's first sea turbine generating station. The pentland firth has some of the fastest sea currents known in the world. Plan is to place 300 turbines in this piece of water. Then about 40 miles south east of pentland firth the biggest wind generating farm in europe is going to built. This should give scotland a massive gut of electricity avaliable to sell to other countries. Total cost is £1 billion pounds. A huge commintment to green energy.

[oil pan 4]

How much power will they make?