Tidal energy could be huge – why isn't it?

It's estimated that we could (practically) capture enough tidal energy to power all homes in the United States TWICE over – but we can only manage a tiny fraction of that right now. For a planet that is 70% water, why is this technology still so far behind other renewables? Are things about to change?

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#PlanetA #TidalPower #TidalEnergy

Reporter: Aditi Rajagopal
Camera and video editor: Henning Goll
Supervising editor: Kiyo Dörrer, Malte Rohwer-Kahlmann, Joanna Gottschalk

Special thanks for the background interviews:
Lisa MacKenzie and Matthew Finn, The European Marine Energy Centre
Andrea Copping, Pacific Northwest National Laboratory
Thomas Adcock, Oxford University

Read More:

IEF on Tidal Power:

Tidal Energy Outlook:

How tides work:

All about tidal range:

All about tidal stream:

00:00 Intro
00:49 What are tides again?
01:58 How does tidal power work?
02:59 Tidal range power
06:15 Tidal stream turbines – the new kid on the block
07:36 A barrage of costs
09:31 What about the environment?
11:08 Conclusion

[DWPlanetA]

Do you think that we should use more tidal energy?

[Herio]

I hate how we point out slightest ecological problem when it comes to any renewable energy source but conveniently forgot that what we have now is devastating whole planet. It's like discussing what type of extinguisher will corrode door handles the least while whole building is on fire.

[mohdazminishak]

Thank you for being transparent about the real environmental, ecological and operational cost impact when talking renewable. Very rare indeed…others tend to overpromise and oversimplify the issue

[NirvanaFan]

I can't believe that I'm nearly 40 and never realized that high-tide and low-tide is us moving around the tidal bulge zone - like how sunrise and sunset is us moving past the sun.

[richardminnich]

AS I recall, one of the problems that they had in the Bay of Fundy (in addition to issues with fish, seals, etc.) was that the tidal forces are so strong that the experimental units just disappear - they are torn out of the bottom of the bay and swept away.

[scottnunnemaker]

It’s been a while since I’ve looked things up on tidal power, but I think there was concerns about marine life being affected by the spinning propellers, things like sharks and rays that are attracted to electrical fields, and possible pollution from leaking components.

[echothebm]

Fun fact. My dad was one off the supervisors for the original Tidal power project in Hammerfest (Norway). (Specifically in Kvalsund)
They look like small underwater wind mills

[theoroder]

I would love to see some comparable numbers in Diagramms or similar. Some number which here for example compare investment costs and efficiency values. That would help me a lot. Keep it up, love your videos

[WindowsR]

0:13 I love how they simulated a fish getting hit

[Clodhopping]

A guy I know (PhD from UMIST and various engineering patents) had a concept for using tidal turbines in the British Channel. He'd conceived a innovative design to compensate for the tide turning and for minimum maintenance to the moving parts and no need for complicated systems. Very simple/effective. I illustrated the visuals and he proposed it to the UK Govt (the then Dept of Energy) with semi-detailed plans and he wanted nothing for it as he'd made his money and was semi-retired) but the Govt couldn't take concepts to design themselves - they needed him to develop the business, create prototypes, etc. Plus the environmental lobby opposed any bankside development on the Severn.

It was interesting to see the Dept of Energy release an article in the Times about a year later, with drawings very similar to mine but they'd misinterpreted some areas and created a more complex but less efficient design that would cost times as much. Always wondered if it was a missed opportunity as UK waters are nothing but tidal? 🤔

[normferguson]

In 1970’s at university we talked about harnessing the Nova Scotia’s Bay of Fundy tidal currents. Eventually permanent turbines were put in. The tides wrecked the machines and they were removed.

[BBountyHunter]

One thing not mentioned in this video in regards to marine life is the production of electricity and resulting change in magnetic field characteristics around the turbines. Lots of fish can detect magnetic and electric signals from quite a distance. Putting some extra sources of magnetic field in the ocean could potentially disrupt the ability of these animals to navigate.

[TubersAndPotatoes]

Artificial lagoons will make great tourism areas too, just hope they can find a way to minimize environment damage.

[jantschierschky]

One aspect comes to mind, modern cruise ships use large diesel electric pots for propulsion. So lot of R&D is done already and there is a manufacturing chain in place, how hard would it be to adopt those for tidal power ?

[pizzasaurolophus]

We had tidal turbines here in Nova Scotia where we have the biggest/strongest tides in the world. But the companies trying to install them eventually went bankrupt, they also harmed a whole bunch of marine life.

[aaronm]

I'm surprised that transportation and storage of energy was completely skipped. Tidal energy is great for the coasts, but all land locked cities are going to need some other energy alternative. I was hoping they would talk about energy loss over vast distances, how many batteries would be needed to store this energy, what chemicals are used in the manufacture of batteries, and the waste/lifespan of said batteries. It is disturbing to me that when alternative energy is talked about these are very important and are never mentioned!

[eckosters]

I live on the shore of Minas Basin, an arm of the Bay of Fundy. We have the world’s highest tides (with a range between 8 and 18 meters) and tidal power has been discussed here for a very long time. The 1 Canadian plant that you mention is further down the Bay of Fundy, it’s in fact a dam in one of the rivers feeding into the Bay. It opened around the same time as La Rance but stopped operating 3 years ago. The renewed in-stream tidal power initiative started about 15 years ago. The Government built an interpretive Center at the site where a tailor-made cable from three turbine locations comes ashore. A donut-shaped turbine was installed twice and both times failed within days. And then couldn’t be removed because of the strength of the currents. We are nowhere near even a pilot project after all these years. In addition, the fishing community is dead against it, causing endless delays.
There have been much better successes around Shetland and Orkney. I’d love to see more progress here but I don’t have much hope

[UninstallingWindows]

I guess the biggest problem with tidal energy is that ocean is a harsh environment. Fixing things or keeping them clean and in working order is tough.

[erinrising]

I wrote a paper in middle school about this very thing. I would like it to be more widely utilized, just so my 13 year old self will feel vindicated

[hugheaston]

What they're not telling people is that the average energy content of the tides per unit area of ocean is extremely small, far too small to do anything useful with. Only in a very few places in the world are the tides strong enough to get useful amounts of energy out, and even then, it turns out you don't get much electricity. Yes the French plant produces 250 MW, but what they don't tell you is that that's the peak output. Most of the time it sits there doing nothing, and only produces the 250 MW briefly near high and low tide. The rest of the time it generates nothing.

As for tidal flow, that demonstration plant is installed in the Orkney islands, which have the strongest tidal flows in the world. it generates a whopping 2 MW (peak), one 15, 000th of the UK's average demand for electricity. Put it anywhere else and it won't generate as much electricity, in fact in most places it'll generate nothing at all, apart from higher bills for the electricity consumers forced to pay for this nonsense.