The Problem: Limited maturity of wave power
Earth Overshoot Day is the hypothetical calendar event, marking the day when humanity consumes more resources from nature than our planet can renew and regenerate in the entire year. In 2018 it fell on 1 August — to date, the earliest the event has occurred in history.
A decade ago, in 2008, Earth Overshoot Day fell almost three months later, on 26 October. Little wonder when energy demand has been pushed up by 20 per cent in the last 10 years.
It’s clear: natural resources are dwindling and being used faster than ever before, despite daily headlines warning of the dangers of global warming, energy consumption, and carbon emissions. Ultimately, humans are living on credit, and that is unsustainable in the long term.
Currently, there’s no way around the problem. People are being told to consume less energy; while concurrently developing new ways of harnessing natural resources. For many, the challenge ahead is like fighting an inevitable tide. But, to others the solutions have been right in front of us the whole time.
Consider, for example, that approximately 71 per cent of the Earth’s surface is covered in water. That represents a vast potential for clean renewable energy, plus fresh water production. At present it is a hugely untapped resource.
Because water is around 1,000-times denser than air, potential conversion into renewable energy is extremely efficient. In 2013, a British government study suggested that by optimising both tidal stream and wave power — which is much more predictable than wind power, and increases in the winter months, when electricity demand is higher — it could meet up to 20 per cent of the United Kingdom’s electricity requirement.
“Between 200 and 300 megawatts of generation capacity may be able to be deployed by 2020, and at the higher end of the range, up to 27 gigawatts by 2050,” the report states.
A 2010 report, by the American Society of Mechanical Engineers, went further, estimating that 3.7 terawatts can be generated from wave energy alone — close to double that of the world’s present electrical consumption.
And yet, the wave power industry is underdeveloped and immature. As the Department for Business, Energy and Industrial Strategy’s guidance says: “With its excellent marine resource and its expertise in oil and gas exploration, the UK is in a unique position to benefit from this type of renewable energy — and to develop related wave and tidal stream services. The industry is still in its early stages however, and further research is needed to determine how best to exploit these assets.”
The solution: Ride the waves of change
Experts have, for decades, been puzzled by the complex process of capturing wave energy. Most of the traditional systems are expensive and ineffective. Sam Etherington has made it his life’s mission to revolutionise the renewable energy sector by discovering a more cost-effective and efficient way to harvest wave energy. After years of development, and having to “go back to the drawing board” on numerous occasions, he believes he is close to perfecting a truly “game-changing” product.
The 28-year-old entrepreneur launched his MANTA device in July 2018. It is a wave energy generator, inspired by the wingspan of Manta rays, that converts the rising and falling of ocean waves into electricity by simply applying the laws of nature. The pilot scheme began its final testing phase at a salmon farm off the coast of Shetland over the summer, and it is anticipated that the commercial product will be available on the market in early 2019.
Sam, who learned his trade by working at his family’s engineering business in the North-West of England, focused on generating electricity from waves during his industrial design degree at Brunel University. He graduated in 2013 — the same year he was crowned UK victor in the James Dyson Award.
He won the prestigious award with a multi-access wave energy converter that absorbed waves from any direction, which increased efficiency and power output. But, as he was soon to discover, nature is a notoriously terrible business partner. Since his first invention, Sam has had to “pull the plug and start again six times” because of insurmountable design snags, nevertheless he is enthusiastic about his MANTA.
“With global energy consumption increasing, there is a great need for renewable power solutions, and while at university I thought that no-one had really figured out wave power, so the door was wide open,” he says from his organisation’s base near Kendal, Cumbria.
“For me, nature is the starting point; the environment maintains balance independently of any human input. When tackling climate change, it seems logical that we should look to nature’s blueprint for answers.
“Engineering was once dominated by electrical and mechanical engineers. Now design engineering is rising to the fore and empowering a new generation of engineers to develop a more holistic approach to problem-solving. My ambition is to launch MANTA into new and existing markets, and to continually strive for ‘carbon neutral’ design. I’ve scratched my head about this for years and I think this design has great promise.”
It is important to explain that waves are distinct from tidal surges created by the gravitational effect of the moon as the Earth spins on its axis. Put simply, waves are caused by wind across the oceans, and compared to wind and solar power, they are much more consistent and predictable.
In September 2012, with a year remaining at Brunel, Sam established his first organisation in this field. Renewable Wave Power was superseded by Aqua Power Technologies Limited — his current business — in June 2014, and raised significant seed funding. And he worked on different technologies before inventing MANTA at the end of 2016. Right now, he says, one MANTA device has the potential to power a handful of homes.
Unlike the established alternatives of seabed devices, which are costly both in terms of financial experience and to the environment, the MANTA is submerged to about 10 metres underwater — allowing it to operate in a calmer aspect of the water column — lightweight, and has a large surface area to harness the full power of the wave. The MANTA’s wings, connected to any floating object by a chain, are hydro-dynamically moved up and down by the motion of the sea, creating a very sensitive system, even in small waves.
“These devices, which weigh just over a ton, are very small in comparison to some of the other devices out there,” explains Etherington. “They are three-and-a-half metres tall, two metres wide, and two metres deep. The MANTA hangs below a float which is about three metres in diameter, by a metre high.
“In terms of power, the machines have an integral capacity of 4.6 kilowatts, which is enough to comfortably cover five homes in optimal conditions. The MANTAs are all hooked up to a big battery array, and they charge the batteries to store the energy when the waves are intense to provide a stabilised power output — so when there are no waves you’ve still got power stored.”
If the MANTA pilot goes to plan, Etherington is aiming to ramp up his business in early 2019 and roll out a commercial version en masse. He says: “In February it will have seen a winter and, all being well, I’ll look to go into a further fund round and take on two people with specialist skills — at the moment it is just me that works full time, and I contract out specialist elements. The commercial design is ready, but it’s just not being made until we’ve had this device in the water, so we can deal with the inevitable teething problems.”
It is feasible, therefore, that by summer 2019 Etherington’s MANTAs will be clustered all around the coast of Britain, as well as is waters further away, as the demand for better wave power become stronger. “There are a few devices out there, but they are all prototypes,” he adds. “I’m very determined to be the one that makes this work on a large scale.”
Q&A with Sam Etherington, founder of Aqua Power Technologies
What is the difference between tidal power, and wave power?
“There is always confusion over this. Tidal power deals with the flow of water; the movement of water in and out in an estuary, say. Whereas wave power, which is what I am more concerned with, is purely the rising and falling over water, and extracting the energy from that.”
How did your experience as a kitesurfer inform your work?
“It was not an epiphany, as such, but when I was learning how to kitesurf I spent a lot of time in the water, and was bashed round a fair bit. It reaffirmed for me that wave power is a huge resource that we should be making the most of. The idea didn’t spring out at me; rather, I went back to the beach thinking: ‘Gee-whiz, there’s a lot of power out there.’ The idea really came from looking at the limitations of other devices. I would literally sit in a room on my own at Brunel thrashing out ideas.”
From conception to MANTA’s deployment in May 2018, what missteps did you take?
The general idea was spawned out of a fair amount of ignorance, because I did not know the industry inside out when I started. It was refreshing in some respects, as it didn’t restrain my thinking. In hindsight I can clearly see the issues I had missed. It gave me a great chance to learn, though. I won some awards — including the James Dyson Award — and then a couple of grant bodies came to me asking me to continue my design. After about six months I realised that there were going to be some serious issues. So it was halfway through the development of that original design that I pulled the plug and started again. I did that six times, and now the device we’re working on, the MANTA, is the one that is showing the most promise.”
It must have been heartbreaking to rip up your plans six times?
“Yes, but it is only when you do deeper work on something that you realise its flaws, or its issues. If there are too many then you have to start all over again. There is a never-ending supply of ideas, and each one has been honed and refined by the learnings of the previous ones.”
How did winning the James Dyson Award in 2013 spur you on?
“Looking back it’s actually played a pretty significant part in everything since, and become more useful as time has gone on. Everyone knows that Dyson is synonymous with good design, and the accolade has helped with funding, I believe. It has certainly been valuable to me because I have been able to use it to leverage investment, and at this stage — as I plan to roll out a commercial product in the near future — that is crucial.”
Words: Oliver Pickup
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