Floating wind turbines and tidal lagoons are excellent examples of disregarded and underused technologies that are unquestionably advantageous for countries with large swathes of coastline, like France. EurActiv’s partner La Tribune reports.
Bouygues Travaux Publics and Ideol have announced the construction of floating wind turbines off the coast of western France. As opposed to its fixed cousins, which have to be anchored to the seabed, floating turbines are one of a plethora of technologies that allow the production of energy by harnessing the power of the waves.
These marine renewable energies (MREs) have the same advantages as other renewable energies, such as no greenhouse gases and contribution to energy independence, but without some of their disadvantages, like land usage issues and negative public opinion. Additionally, their energy source, the sea, is more predictable than other sources and as such they can be used as a constant energy supply. This is why they are particularly suited to providing energy to island communities that are otherwise isolated.
These facts were presented at the Seanergy fair in Biarritz on Thursday (2 June). It was highlighted that despite these numerous advantages, MREs still account for very little in global energy supply: just 562MW, with 15MW coming from floating wind turbines in 2015. That’s just 0.03% of renewable energy production.
However, a breath-taking, albeit hypothetical, scenario was outlined in which between 20,000TWH and 80,000TWH could be produced globally, or between 100% and 400% of the planet’s electricity demand.
Aside from floating wind turbines, only tidal power is well-established. There is currently a capacity of 0.5GW. However, barrages installed in bays often have to deal with negative public opinion from local residents. Those harnessing wave or tidal power have the best bet of being accepted and have the greatest potential.
Together, these technologies could reach a capacity of 337GW by 2050 and directly create 300,000 new jobs, according to estimates by Ocean Energy Systems. Floating wind turbines could be producing 2GW by 2020, according to Ocean Energy Europe, and between 10GW and 22GW by 2030. The organisation forecasted a 300MW capacity for the other technologies.
However, these estimates do not take into account changes to the regulatory framework. In its “450 scenario”, which is compatible with the aim of limiting global warming to under 2 degrees Celsius, the International Energy Agency (IEA) envisaged 36GW of MREs by 2040.
These differences highlight the importance of public policies and their currently limited ambition. Yet, incentives for R&D, development and investment in these sectors have emerged over the last few years in the countries best placed to tap into their potential.
The competitiveness of MREs is currently stymmied by a number of difficulties, including connection to the grid and obtaining permits to construct installations offshore. This is why public support and prototypes built to scale are needed to boost the sector. Studies have revealed the potential to cut costs between the prototype and commerical phases, which lies in economies of scale, full sea trials and finding the best ways to build, run, maintain and dismantle the installations in a very specific environment.
Grouping several MREs in one site would also allow maintenance and operating costs to be shared.
France is extremely well-placed to exploit MREs, given its 11 million square kilometres of sea, including overseas territories; the Ministry of Ecology estimates a potential of between 3GW and 45GW.
Several tenders have been launched in recent years and a number of projects have been developed since 2014, particularly tidal farms. Several demonstration models and pilot projects have also been connected to the grid.
In April, eight floating wind turbine projects were submitted for consideration and calls for tender are in the pipeline.
Overseas communities, where power generation can reach €500/MWh, offer ideal testing grounds for MREs. There is the potential for, for example, French Polynesia to meet its target of 50% electricity generation through renewables by 2020.