WaveRoller energy: Why the sea is the world’s biggest battery

WaveRoller energy: Why the sea is the world’s biggest battery

Electricity generating WaveRoller technology has two advantages that wind turbines lack: sea power and beauty. It brings far more local business benefits too, as Nick Booth explains – with added IoT and AI potential.

We need to do something about the sea. It already covers seven-tenths of the planet and teems with life, but that’s not enough for it, apparently. Thanks to global warming, it’s now moving in on our territory and eating into the land.

For example, large sections of Britain’s eastern coastline are regularly lost to the waves, thanks to the sea’s aggressive expansionism. Call it revenge for our carbon emissions.

One way to appease the oceans might be to lower our carbon consumption. But on the other hand, we could engage the waves and get them working for us – and help reduce global warming at the same time.

We are missing out on a huge opportunity by not doing more to harness wave energy, according to Christopher Ridgewell, CEO of green-tech company, AW-Energy. The sea is the world’s biggest battery, he says, and the company’s WaveRoller technology seeks to use that power – the largest untapped resource in renewable energy.

The sun’s energy creates winds by warming the land and sea, causing air currents. In turn, these create waves that complement the tidal power of the moon’s gravitational pull. Their joint momentum creates a potential that could be converted into hundreds of gigawatts of electrical power, he says.

AW-Energy’s WaveRoller is an oscillating wave-surge technology that converts waves into electricity, via moving steel panels. Since the technology sits on the sea bed, it has a lower centre of gravity than a wind turbine. This makes it much easier and cheaper to install and maintain.

Brine power is aesthetically pleasing, too. WaveRoller’s supporting infrastructure blends into the undersea ecosystem, with flora growing onto it, which means that fish and other marine fauna can be encouraged to thrive around it.

• The EU-funded technology was first tested at full scale in locations around Europe between 2016 and 2017. A full rundown of the technology’s development history is available here.

A WaveRoller installation.

Local employment

Wind turbines have other drawbacks: they don’t integrate well with human communities. For example, they fail to create local employment, because their installation and maintenance calls for specialist ships, drones (increasingly), and skills, all of which are invariably brought in from overseas suppliers.

So there are few economic dividends for local business, despite turbines’ dominance of the landscape.

By contrast, WaveRoller installations typically avoid these problems. First, they sit on the sea bed, and so are visually unobtrusive. Second, the technology uses a more reliable source of momentum than wind, since waves are regular and highly predictable (see below). The money markets like stability and reliability, which theoretically makes it easier to obtain finance.

WaveRoller stimulates the local environment, too. The base upon which the blades and the turbines sit can be manufactured locally, which cuts down on shipping costs. Indeed, it calls for shipbuilding skills, which creates employment for local craftsmen and women – often in regions where this work is now at a premium.

“It could brings jobs to any area with a tradition of shipbuilding,” explains Ridgewell. “I grew up in Newcastle and I used to walk past the shipyards and saw their gradual decline.” He now sees WaveRoller as an opportunity to make new waves of local investment.

Further economic stimulus is provided by the demand for maintenance staff, such as engineers and power experts, who can all be sourced locally.

IoT management opportunities

But while the technology exists for converting waves into watts, brine power needs careful monitoring and management. That isn’t so simple, given the harsh conditions in which the devices will be placed, and will operate.

The energy that WaveRoller captures needs to be managed too, since there is still a local mismatch between the ocean’s variable supply of power and the constant demands that industries and consumers make of the national grid.

This is where the Internet of Things can extend the reach of energy management and solve the storage and distribution challenges.

The WaveRoller’s power take off (PTO) subsystem is separated into two further systems. One captures the power and the other oversees its distribution – which covers everything from electrical power generation to storage. Separating the subsystems allows the power-capture process to be fine-tuned for each environment, regardless of the demands of the local electricity grid.

By the same token, a separate power-storage system allows production to be adapted to local power-quality requirements, such as power ramp-down and ramp-up in either calm or stormy conditions.

The power-capture subsystem’s machine-learned intelligence allows it to automatically adjust to these conditions, by controlling a counter-force of hydraulics – the PTO counter torque that captures the maximum energy from each wave, depending on its size.

The system was designed using hazard identification and FMECA (failure mode effect and criticality) techniques to obviate risk and determine the load cases for the design. The rationale is to make sure that entering failure mode doesn’t overload the system.

Through its artificial intelligence capabilities, each WaveRoller develops a surfer’s instinct for each coming wave, in order to judge how much power to deliver to the grid and how much to keep in reserve.

This ‘artificial instinct’ is necessary because it has to make these decisions at an early point in the energy-conversion cycle. This helps it to ramp the delivery of power at a smooth rate, in order comply with national grid standards.

Sensors distributed throughout the supporting infrastructure and panels feed intelligence on variables such as system pressure, temperature, and motion.

More, the management system has several degrees of alarm that can be registered and reported before it takes action to shut down an installation if it judges that the devices need protection from the elements.

All together, WaveRoller should make waves in local energy systems worldwide, as well as stop all of that energy from going to waste.

A steel WaveRoller blade.

Plus: How music improves brine power

AW-Energy’s wave energy conversion concept is being boosted by an unexpected spinoff – from auditory neuroscience.

It all started when Ridgewell and Patrick May from the the Leibniz Institute for Neurobiology – currently working at Lancaster University in the UK – were discussing neuroscience over a beer. They posed a theoretical question: “How can one play violin in an orchestra when your ‘mind model’ of the surroundings is always half a beat delayed?”

The point is that sound and water both share the same properties – waves – and waves of any kind take time to travel through their environment. As a result, it is possible to predict their movements.

Ridgewell and May went on to explore the application of models developed in auditory neuroscience to manage the real-time prediction of individual waves. This research was to provide the intellectual foundation on which WaveRoller’s optimum power take off (PTO) system was created.

May’s previous work on modelling the brain’s auditory system and speech recognition ability – combined with machine learning methods – now forms the basis of the dynamic prediction system that is necessary for the optimum conversion of sea waves into energy.

If Ridgewell has a scale model of the WaveRoller on his desk and you held it up to your ear, you could probably hear the sea.

Internet of Business says

The safe, long-term, predictable, and sustainable advantages of wave technology would seem to be a must for investment, particularly in countries with long coastlines, where many governments are currently investing in offshore wind farms. WaveRoller’s local employment advantages would seem to make it an attractive proposition all round.

We welcome Nick Booth to our writing team.

Nick Booth is a freelance technology writer and editor whose clients have included The Guardian, the Daily Telegraph, Computer Weekly, Silicon, Business Cloud News, Data Centre Dynamics, The Inquirer, ZDNet, V3, and The GSMA. In addition, he has edited Times supplements on retail technology, digital banking, business intelligence, green motoring, outsourcing, business continuity, and IT security.

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