Placeholder Image

Subtitles section Play video

  • You can imagine

  • that the oceans are actually the largest battery.

  • We're storing huge amounts of energy in the oceans.

  • The wave motion can be very deep.

  • It can extend down several hundred meters,

  • and once it gets to the near shore, from about 50 meters,

  • the whole water column is moving backwards and forwards.

  • As we search for ways to reduce our reliance

  • on fossil fuels, some are looking

  • to a largely untapped potential source of renewable energy.

  • In theory, waves off the coast of the United States alone

  • could generate over two trillion kilowatt hours

  • of electricity a year,

  • enough to power more than half of the country.

  • Waves intensify and subside not as quickly as the wind,

  • and that means that it can produce

  • a smoother power generation curve.

  • One of the potential advantages of wave energy is

  • that it could act as a complementary source of power,

  • compared to other renewables on the grid

  • if it were to be scaled up to a commercial scale.

  • For decades, engineers have been trying

  • to convert wave energy into electricity

  • but a host of technological

  • and financial challenges have complicated their efforts.

  • In the years from around 2006 to 2015,

  • there were a spate of bankruptcies in the sector,

  • and this was largely because of a lack

  • of kind of continuous proven projects out at sea

  • with reliable electricity generation.

  • Since then, companies have been trying

  • to develop the technologies at a steadier pace

  • and with a smaller cash burn.

  • But the same questions remain.

  • Can companies develop devices

  • and technologies that actually work?

  • Is wave energy just a novelty or something

  • that can become a major renewable energy source?

  • The sea is a very challenging environment

  • within which to operate a power project.

  • So seawater is corrosive and conditions are very rough.

  • So this means that power projects

  • don't have a very long lifetime

  • and it increases operating and maintenance costs.

  • Partly because of that,

  • many early wave energy projects hit rough waters,

  • such as the Pelamis wave energy converter in Portugal

  • and the Islay LIMPET project in Scotland,

  • but that hasn't stopped others from trying.

  • Companies are focused on testing projects out at sea,

  • proving their durability, trying to raise capital

  • and bring down cost.

  • The sector hasn't really converged

  • around one single technology design

  • and companies are kind of undecided

  • about which design works best.

  • Finland-based AW Energy is a veteran in the sector.

  • The first proof of concept of the company's device

  • was made in the '90s after diver Rauno Koivusaari

  • observed the strong back and forth movement of a hatch cover

  • in a shipwreck in the Baltic Sea.

  • The waves are generated far from the coastline.

  • So the wind blows on the surface of the water

  • causing the water particles to rotate.

  • And that rotation extends deep down below the surface

  • and the waves can be very long,

  • they can be several hundred meters long,

  • and as they come into the near shore,

  • this rotational energy turns into an elliptical energy

  • and eventually backwards and forwards

  • that you probably have noticed if you've been swimming

  • on the seashore in large waves, you're pulled in and out.

  • That's the energy that we're extracting

  • but there's a sweet spot where we deploy.

  • So around 10 to 15 meters of water depth,

  • that's where there's still strong wave energy coming in.

  • After years of research, prototyping and testing,

  • the company has deployed WaveRoller,

  • a 350-kilowatt device in the waters off Portugal.

  • WaveRoller has an 18-meter wide

  • and 10-meter high steel panel fixed to the seabed

  • via a floatable foundation.

  • The panel moves back and forth with the waves,

  • capturing the energy.

  • It's submerged in the depth of 15 meters

  • so it's protected from the extreme waves.

  • We generate electricity by capturing the movement

  • with hydraulic circuitry

  • in a machine room underneath the surface.

  • That hydraulic energy we turn to electricity

  • with hydraulic accumulators and hydraulic motors,

  • and also a generator.

  • The WaveRoller has survived large waves at sea

  • for over a year and delivered electricity

  • via an underwater cable to the grid in Portugal.

  • Meanwhile, the company has won a 2.5 million Euro grant

  • to work on an upgraded version of the WaveRoller,

  • aiming to increase the electricity generation capacity

  • to one megawatt.

  • The upscaled device would have a bigger panel,

  • two power takeoff units,

  • and improved software to control the energy production.

  • We have taken into use a wave prediction algorithm

  • that kind of tells us what kind of waves

  • are coming in to our device.

  • That gives us a few seconds to prepare

  • for capturing more energy

  • and the difference in that is significant.

  • Our future plans are to deliver technology

  • around the world.

  • So I'm hoping we can be working on delivering technology

  • to projects in Asia

  • and also in the American continent as well.

  • Meanwhile, Israeli company Eco Wave Power

  • is taking a different approach

  • to capturing the power of the ocean.

  • For the company's founder, Inna Braverman,

  • developing new sources of renewable energy

  • is a personal mission.

  • I was born in Ukraine in 1996

  • and two weeks after I was born,

  • the Chernobyl nuclear reactor exploded,

  • causing the largest in history nuclear disaster.

  • I was one of the babies that got hurt

  • from the negative effects of such explosion.

  • I had a respiratory arrest and a clinical death.

  • Luckily my mother, a nurse, approached my crib one time

  • and gave me mouth-to-mouth resuscitation

  • which saved my life.

  • I got a second chance in life

  • and decided to do something good with it.

  • Growing up, Inna wanted to be a politician

  • to positively change the world.

  • After working as a translator at a renewable energy company,

  • she decided to change paths.

  • Solar and wind energy were fully commercialized.

  • There were a lot of amazing technologies

  • implemented everywhere.

  • I saw that wave energy,

  • although it's an immense source of electricity,

  • the biggest companies in the world

  • are trying to develop wave energy with no success.

  • And there was kind of a race going on in the world

  • of who is the company that is going to develop

  • a viable wave energy solution first.

  • In 2011, the then 24-year-old Inna

  • co-founded Eco Wave Power.

  • Instead of installing devices offshore,

  • the company's devices are attached

  • to existing breakwaters, jetties and piers.

  • Our technology is very cost efficient,

  • especially in comparison to the offshore technologies,

  • because we don't need any ships, divers,

  • underwater mooring or cables.

  • We install on existing manmade structures

  • and all our expensive equipment, the generator,

  • the hydraulic conversion unit, the automation,

  • is located on land, just like a regular power station.

  • This is the Eco Wave Power conversion unit

  • that has been operating in Jaffa port since 2014 until 2020.

  • Here you can see how the technology works.

  • Basically the floaters are going up and down

  • and pushing the hydro cylinders

  • which transmit biodegradable fluid

  • into land-located accumulators.

  • A pressure is being built,

  • the higher the waves, the higher the pressure,

  • which is used to turn the hydro motor

  • which is turning the generators.

  • The whole system is controlled by a smart automation system

  • which you can see right here.

  • And in case of a coming storm,

  • the system automatically raises the floater

  • above the water level and keeps them in the upward position

  • until the storm passes.

  • The company has been operating

  • a 100-kilowatt grid-connected device in Gibraltar since 2016

  • which is enough to power 100 households.

  • Currently Inna and her team are working

  • on another 100-kilowatt project

  • at the port of Jaffa in Tel Aviv.

  • The project will be also the first time in the history

  • of Israel that wave energy will officially connect

  • to the electrical grid.

  • And our goal going forward is to expand it

  • to all suitable breakwaters in the city of Tel Aviv

  • and to supply a significant part

  • of the city's electricity needs.

  • Today, engineers and entrepreneurs

  • are still trying to crack wave energy.

  • Globally, only a few hundred kilowatts

  • of wave energy are deployed

  • compared with gigawatts of offshore wind.

  • But the field has come a long way in recent years,

  • and with the right engineering solutions

  • this new power source could eventually become competitive

  • with more mature renewables, like solar and wind.

  • I would have a lot more confidence in the success

  • of wave energy companies today

  • as opposed to, like, 20 years ago.

  • But in the next few years,

  • or maybe the next couple of decades,

  • it will be more likely to be used in remote locations,

  • like islands, that are otherwise dependent

  • on expensive diesel power,

  • or out at sea on gas decommissioning rigs,

  • or for powering underwater autonomous vehicles.

  • So definitely wave energy can compete

  • with other renewable energy sources,

  • but I personally believe that this is not a competition.

  • In order to have a 100% renewable energy friendly world,

  • we need all renewable energy sources to work together.

You can imagine

Subtitles and vocabulary

Click the word to look it up Click the word to find further inforamtion about it