Can marine renewables ever be mainstream?

The marine renewables industry is picking itself up after the disappointments of cuts to subsidies and the government’s decision not to support plans to build tidal lagoons in Swansea Bay. But where does wave and tidal technology go now? Catherine Early reports.

However novel and appealing the proposal is… the costs that would be incurred would be so much higher than alternative sources of local carbon power, that it would be irresponsible to enter into a contract

Though the statement by energy secretary Greg Clark concerned the Swansea Bay tidal lagoon project, its message to the renewable energy industry was implicit: a technology may be innovative, but if the government judges that it is too expensive, it will not be supported.

“I don’t see any real appetite for innovation in construction with this government at the moment. It’s not so much the death of innovation, it hasn’t started,” said Tidal Lagoon’s executive chairman Keith Clarke. The company is now trying to regroup, and it would be premature to discuss its future, he said.

A spokesman for the firm added that tidal lagoons are fundamentally different to other energy assets, and require new ways of thinking. “We saw no appetite from government to think differently, which suggests there’s a systemic obstacle to innovation.” New technology needs a system capable of appraising new ideas on their own merits and not merely in reference to the status quo, he said.

Since then, the government has also dismissed calls from the marine renewables industry to provide separate support for its technologies through the Contracts for Difference (CfD) support mechanism. An announcement of the next auction round in May 2019 revealed that wave and tidal technologies would have to once again compete head to head with offshore wind.

This was the case in the 2017 auction, which saw no marine or tidal capacity win a contract. Developer Atlantis had bid for a contract for the next phase of its MeyGen tidal stream project in Scotland’s Pentland Firth, but despite cost reductions of two-thirds compared with an earlier phase, it failed to beat offshore wind on price.

Richard Graham, MP for Gloucester and chair of the All-Party Parliamentary Group on Marine Energy and Tidal Lagoons, said that despite the setback of Swansea, it was not the end of the story for either tidal lagoons or the wider marine energy sector. But the government needed to be clearer about how it would compare the costs of different energy sources, he said.

Cutting costs

“How do you compare a price for marine energy relative to sources around for almost 60 years (nuclear) or much shorter periods (wind): but which have reached their current price after c£18 billion of subsidy?

“If everything is priced from the latest offshore wind bids of CfD of £55 per kWh, the chances of much marine energy being added to the mix are very modest,” he says.

The sector is adamant that it can bring costs down. A report published in April by the Offshore Renewable Energy Catapult estimated the potential for tidal stream technology to cut its levelised cost of energy (LCOE) from £300/MWh to £150/MWh once 100MW was installed, reducing to £80/MWh after installation of 2GW.

Cameron Smith, director of public affairs and business development at Atlantis, says that the industry does not need a huge amount of help for innovation to become commercial reality. “The technology is at the stage of becoming potentially huge. We just want some support for the first 200MW or so of projects,” he says.

Trade body Renewable UK (RUK) has developed a potential solution. Its Innovation Power Purchase Agreement (IPPA) uses tax incentives rather than consumer-funded subsidies. Under an IPPA, a corporate would agree to pay above the market price – at a level set by government – for the energy generated by a wave and tidal stream project.

The corporate could then reclaim the additional costs as a tax rebate through the normal tax return process. It proposes that built-in thresholds would reduce the level of support available as technology matures, ensuring that the government’s overall exposure is limited.

There is a lot of appetite from corporates and energy intensive industries to source renewable energy to increase energy security, and to help meet carbon reduction targets, points out Luke Clark, head of external affairs at RUK. “The IPPA would take the cost of innovation off consumer bills and make it more of a taxation measure,” he says.

Graham believes that the idea has merit. “I look forward to seeing the government’s response to the IPPA. I’m optimistic that both ministers and officials will engage more with marine energy, which is after all what Greg Clark promised.”

Ring-fenced support

If the government continues not to support it, the sector is already talking about moving its innovation overseas. France and Canada are supportive of marine energy, with other countries in Asia, including China, showing an interest. Atlantis already switched its focus overseas in 2016, when the government removed the ring-fenced support for marine technologies. It has a 50 per cent stake in a 4.5MW project in Canada, and contracts and project development rights in Indonesia, China and South Korea. It is also talking to the French government on the development of large-scale arrays in Normandy and Brittany.

Simon Forrest, chief executive of tidal turbine developer Nova Innovation, said that the UK was blessed with predictable tidal resources, and a technology development lead of at least two years on other countries. “The most galling thing is that we’ve got all the ace cards, and we’re about to throw them all away. We did the same thing on wind energy, in which we led the world back in the 1980s. We pulled back just as the technology reached commercialisation,” he recalls.

Denmark took over development of the technology, and now the sector has an export value of €7.3 billion. “We effectively gave away something the size of our defence industry,” he says.

Clark agrees that the UK could be risking a valuable opportunity. “Without a domestic market to anchor firms in the UK, there are concerns that we would start to lose out to other countries. Because this is an emerging industry, the supply chains are less fixed. Manufacturing has taken place in the UK, but when the industry starts to take off internationally and supply chains become established, that’s where the danger of the UK losing out is.”

However, Richard Howard, head of research at Aurora, is sceptical about the export potential of marine renewable technologies, given the lack of development across the globe. “Maybe once the technology is mature there might be an export market, but I’m not sure. Other countries are looking at these technologies, but in solar you see tens of gigawatts deployed every year, while in wave and tidal you see tens of megawatts. It’s a different order of magnitude,” he says.

While he believes that the government has a role to play in supporting innovation, this is getting “harder and harder to justify” for the wave and tidal sector, he believes. “The industry has been talking about the technology maturing for a long time now, but on what basis will costs come down? I don’t know.

“The massive success in driving down the costs of wind and solar energy means that other technology is chasing a number that’s falling faster than they can keep up with,” he says. “It’s hard for government to make a special case for technology that is further behind,” he concludes.

Where are they now?

Several innovative renewable technologies have hit the headlines in recent years. Some are thriving, while others have failed to make it beyond research and development.

Pelamis Wave Power

The movement of five connected sections in the waves was harnessed by hydraulic rams at the joints, which drove electrical generators inside the 180m-long device. The firm’s second generation machine was ordered by E.ON  in 2009. It was tested for three years in the Scottish island of Orkney. The company went into administration in November 2014.

Simec Atlantis

The rotors of the 6MW MeyGen tidal stream array submerged in Scotland’s Pentland Firth harness the power of the marine currents to drive generators, which in turn produce electricity.

Construction and commissioning of MeyGen was completed in March 2018. It has generated over 8GWh of energy to the grid to date, and Simec Atlantis intends to install a further 392MW capacity.

Scotrenewables Tidal Power

The SR2000 tidal current turbine has twin turbines fixed to retractable legs mounted to a floating platform. It is in test phase at the European Marine Energy Centre in Orkney, Scotland.

The technology generated more than 1.2GWh of electricity in the five months to June 2018.

Kite Power Systems (KPS)

This power system features two kites that fly up to 1,500 feet in altitude. Both kites are attached by tethers to a winch system that generates electricity as it spools out.

KPS is currently testing its 40kW system at West Freugh at Dumfries and Galloway in Scotland. Its latest 500kW demonstration model is being manufactured and assembled in Dumfries.

Minesto

This company’s Deep Green technology produces electricity by sweeping a turbine across a large area of the sea, at a speed several times the actual speed of the underwater current. Five prototypes have been built and tested, with the first electricity produced in 2009.

A prototype has been undergoing testing in Northern Ireland’s Strangford Lough. The company is to continue testing, while in parallel building and commissioning the first commercial scale 0.5MW project in Holyhead Deep, Wales. This will be expanded to a 10MW array, with a long-term plan for 80MW of installed capacity at the site.