What lies beneath: Is tidal power the next big wave?

Just under the ocean’s surface, could be one of the most reliable forms of renewable energy – tidal and wave power.

Nathan Lim headshot grab

By Nathan Lim, former International Shares Fund Portfolio Manager at Australian Ethical

 

The world just got a little bit closer to tapping into the ocean’s tides as an energy source. Construction is nearly completed on MeyGen – the world’s largest tidal stream energy project. This array of turbines on the seafloor is expected to begin delivering to the grid in 2016. Its development could be the catalyst that the fledgling tidal energy industry needs.

Is blue the new green?

The seabed of the Pentland Firth’s Inner Sound of the coast of Scotland contains some of the most energetic water in the world. These environmental conditions make it the perfect location for MeyGen.

When it’s up and running, the 398-megawatt array has the potential to power 175,000 Scottish homes. While that’s nothing to sneeze at, the bigger picture is even more impressive: wave and tidal power could provide more than 20% of the UK’s electricity needs – imagine that on a bigger scale!

The MeyGen project off the coast of Scotland is well on track to start producing clean energy by early-2016. Image courtesy of Atlantis Resources.

The MeyGen project off the coast of Scotland is well on track to start producing clean energy by early-2016. Image courtesy of Atlantis Resources.

The unique characteristics of the site (where tidal streams reach up to 5m/second) coupled with the UK’s supportive political environment for marine technology are key to the story of MeyGen. And, the tidal project also has a unique Aussie connection.

The project’s developer Atlantis Resources was founded in Australia. While they’ve been based in Singapore since 2006, the early years of the company were spent developing tidal current turbine prototype designs and concepts off the coast of Victoria.

But the antipodean link doesn’t end there – Australian Ethical Investment is a key investor in the project, committing 9% of the capital raised by Atlantis Resources at its last capital raising.

A new direction for Australian Ethical

While Australian Ethical has an extensive history of investing micro-cap stocks via its Australian Shares Fund, it is the first time that the International Equities Trust has done so.

The decision to support the initiative is due to the project’s potential says Portfolio Manager Nathan Lim. “We believe this particular project has real commercial value. It will generate positive cash flow because a robust energy price has been guaranteed by the UK government.”

The MeyGen project also delivers on what Nathan sees as one of the mandates of Australian Ethical’s International Shares Fund – to support innovation in clean-tech delivery. “Investors want us to go out and look for cutting edge technology. Not technologies that are never going to work – we are not a charity – but things that have real commercial value,” he says.

Tidal stream – what’s it all about?

Tidal stream technology utilises underwater wind turbines that sit inside the current caused by the tides found near coastlines and harbours. Water is 800 times denser than air so tidal stream turbines are a fraction of the size of a comparable wind turbine.

The biggest advantage ocean-powered renewable energy has over wind and solar is it’s consistency; the moon’s cycles are regular and calculable, and so tidal power is very predictable. For a grid operator, this makes it highly attractive. Wind and solar are affected by weather conditions – they need high winds or clear sunny skies to operate. Because they are so dependent on variable weather conditions, the amount of energy they are likely to produce day-to-day is difficult to predict.

Wave and tidal power on the other hand is powered by the moon’s gravitational pull and the rotation of the Earth. Tidal flows can be predicted well in advance and wave power increases during winter, the period in the UK when electricity demand is at its highest.

Around 23% of the world’s population lives near the coast, so from an international perspective, wave and tidal power projects could be developed in proximity to end-users.

Positive policy

Atlantis has spent the past 11 years developing and testing prototypes for the project. The company is looking to anchor as many as 269 squat, three-bladed turbines in the seabed.

“The impact of policy in the UK designed to support tidal and wave energy projects can’t be underestimated” says Nathan – it’s what has made the MeyGen project viable.

Tidal energy technology has been around since the 1960s, but the high costs and technological challenges have prevented its rollout. The future for the industry has begun to turn around though with policymakers worldwide learning from the wind and solar power industry’s history of subsidised production and development.

The UK has positioned wave and tidal stream energy as key to the transition to deriving energy from renewable sources. It’s estimated that the 50% of Europe’s tidal energy resources are located in UK waters.

Tapped successfully, the UK’s Department of Energy & Climate Change believes that wave and tidal energy combined could deliver around 20% of the UK’s current electricity needs. It would also establish the country as the world leaders in a global market worth £50 billion by 2050.

The challenges

The biggest challenge facing the marine power industry, is building effective devices that can withstand the harsh and hazardous environment of the oceans. Long-term reliability is a major focus of those in the industry.

Wave-power-launching

Image courtesy of Atlantis Resources.

The UK government has set themselves the goal of having 120 megawatts (MW) of domestic power generated by tidal and wave projects by 2020. There is still a lot of work to be done to achieve this goal, and after lots of false starts by other marine power companies, Atlantis now seems to be leading the way.

The first turbines to be installed in the Pentland Firth are from Atlantis in collaboration with Lockheed Martin and Andritz of Austria. They will be set on tripods with each leg weighed down by a 200-ton block of cement.

“Atlantis is one of the few companies actually in a position to start delivering,” says Nathan. “They are the only ones who are scaling up and looking to be able to meet the UK’s megawatt demand. This is why I think there is going to be a tremendous amount of value in this company being the world leader in tidal stream technology,” says Nathan.

Water is 800 times denser than air so tidal stream turbines only need to be a fraction of the size of a comparable wind turbine.

Solid political support

“The UK’s Department of Climate Change remains supportive of tidal energy, and Atlantis,” says Portfolio Manager of Australian Ethical’s International Shares Fund, Nathan Lim. “Despite some recent moves to cut support for solar and wind energy, overall we believe the UK government – and in particular the Scottish – remains focused on emission reductions, so renewable energy will have an ongoing role to play.”

Read Next