Wave Energy is a clean, renewable source of power that could supply 10% of global electricity by 2050. The problem is this: how do you harness the hostile power of the ocean to produce affordable energy?
It’s been called the toughest engineering challenge in renewable energy. In other words, it’s just the kind of knotty problem that excites engineers like Dr Gareth Stockman and Dr Graham Foster, the co founders of Marine Power Systems.
The pair met ten years ago while studying PhDs at Swansea University. Gareth Stockman says: “We met through a shared passion for the ocean, engineering and renewables and were soon exploring the potential of waves to generate clean power. This was back in 2008 when wind and solar were gaining a foothold in the marketplace and Swansea University was already doing a lot of work on tidal energy but the wave energy sector was pretty untapped.
Our common interest in finding solutions to engineering challenges kicked in and we were soon using our spare time to develop our ideas.” The project led to some innovations which Gareth and Graham were convinced had serious potential.
A decade of design, testing and problem-solving later, the WaveSub 1:4 scale prototype was launched at Pembroke Docks last October.
The WaveSub captures energy using the continual orbital motion of waves to drive a sophisticated power take-off system. Similar to offshore wind, power is transferred to shore with an undersea cable. Rated five megawatts at full scale, a single WaveSub device will be able to power approximately 5,000 homes; similar in power-output to a large off-shore wind turbine. Based on this, 100 WaveSub devices would be able to power a city the size of San Francisco.
The core focus when designing the WaveSub was ensuring that it could overcome what Marine Power Systems identified in its report Making Wave Power Work (June 2017) as the four main challenges of energy generation at sea: survivability, efficient energy capture, low capital costs and low operational costs.
Talking about the device, Gareth says: “One of the defining features of the WaveSub is its depth-adjustability. This enables it to move through the water, maintaining an optimum power output level at all times. It can also retreat to deep water and shelter itself during storms, eliminating the need for it to withstand huge waves on the sea surface in extreme weather conditions.”
The WaveSub prototype is, at the time of writing, undergoing the first round of tests in the sea at Milford Haven in Pembrokeshire. “The move into sea-based testing is an important step for us,” says Gareth. “We’ve made good progress through the initial stage which is hugely encouraging. The next stage will see us focusing more on its operational energy generation capacity.”
From drawing board to sea trials, Marine Power Systems has been supported by the Welsh Government at every step, says Gareth: “Right at the start, we had some embryonic grant funding for a technical and feasibility study. We built a small prototype in 2009 and completed a significant amount of computer modelling in 2010, to understand if our idea was realistic and could compete with the LCOE (levelised cost of energy) for conventional energy forms and other renewables.”
The results were highly encouraging. Further grants and investment followed. They won several awards. They developed the IP and patented the technology worldwide. They’ve tapped into academic expertise at universities around the UK and Europe – most notably at Swansea University, whose Marine Energy Research Group has helped with modelling and prototype testing. They’ve also benefited from the Astute 2020 programme – Advanced Sustainable Manufacturing Technologies – a Welsh Government-funded project that promotes collaborations between academia and industry.
“The Welsh Government has been fantastic over the past 10 years,” says Gareth. “They’ve helped us at every stepping stone.”
The next step is to build a full-scale prototype and Marine Power Systems is already in discussions with businesses and individuals regarding the investment opportunity. With finance secured and a full-scale device proven, it’ll be ready to take its device to market. Ultimately, its vision is for farms of WaveSub devices deployed, capable of powering towns and cities around the world.
Comparisons are made with offshore wind, which was once an emerging renewable technology but is now a multi-billion dollar industry.
Gareth thinks that wave will advance quickly. “There are many more drivers to accelerate progress now. Along with legally binding objectives to reduce carbon emissions and the need to address energy security, there is also a greater public understanding of the environmental and economic benefits to be gained from renewables. This, combined with rapid advances in technology, means that when we consider wave energy as a future renewable energy source, it has become a case of when, not if, it will happen.”
Marine Power Systems is not alone in the marketplace, of course. There are other competing ideas out there, each trying to secure their share of the future market. This isn’t a bad thing, says Gareth: “Yes, we have competition, but there’s plenty of business for all of us. If we only capture a small percentage of the resource, the economic returns will be significant. Global wave energy resource is huge; ten times that of tidal. That others are working towards the same goal simply shows there is a common belief that harnessing the power of the waves is possible.”
The path set by the wind energy industry is a good one to follow. “The wind energy sector has a substantial number of manufacturers, some of them are making billion-dollar revenues per year,” says Gareth, citing the Danish wind manufacturing success story Vestas as an example.
So is that your ambition for WaveSub? A multi-billion company, with a worldwide presence?
“Absolutely,” says Gareth with conviction. “In the future, when people ask what the biggest companies in Wales are, we want Marine Power Systems to be up there. We want to provide thousands of jobs which pave the way to a low-carbon future. This is the long-term vision we’re working towards. We believe it is entirely possible.”