Maritime renewable energy

December 2018: New devices for ocean energy allow extraction of kinetic energy from tidal and wave movements. Its predictability offers particular value to grid-balancing operators looking for a stable energy supply for remote areas and coastal communities.

Information

Ocean energy technologies aim to harness energy from either tidal or wave motions. Floating turbines in free-flowing waters convert the water’s kinetic energy into renewable power. Generally, blue energy is categorised into tidal or wave energy. While wave energy is in its first generation of concepts, tidal energy recently reached pre-commercial stage with devices having achieved maturity. In light of this, third generation tidal energy converters such as the Orbital O2 by Scottish firm Orbital Marine Power Ltd, use sails, kites, or simulate fish-swimming motions to extract kinetic energy. Advantages of commercially viable ocean energy technologies include the high predictability of tidal flow and the velocity of water moving through areas with turbines. This reduces the need for battery storage to a 4–6-hour window before tides return and recharge batteries. Further, the deployment of turbines close to the water surface suggests only limited impact on marine life.

Implications and opportunities

Ocean energy could help decarbonise economies in coastal regions. It represents opportunities to power remote communities and could act as a complementary energy source to wind and solar generation. Its predictability offers particular value to grid-balancing operators to ensure a stable energy supply from renewable energy sources. Further, its floating platforms allows for easier maintenance than off-shore wind turbines that are planted on the sea floor.

The European Commission classifies ocean energy as abundantly available and renewable. Consequential, they predict that ocean energy could cover about 10 per cent of the EU’s energy demand by 2050 and the Carbon Trust states that 20 per cent of the UK’s total energy supply could come from wave and tidal energy.

Sources

CNBC. (2018). New Designs Unveiled for the “World’s Most Powerful” Tidal Turbine. Retrieved from https://www.cnbc.com/2018/11/19/new-designs-unveiled-for-the-worlds-most-powerful-tidal-turbine.html

European Commission. (2018). Workshop on Identification of Future Emerging Technologies in the Ocean Energy Sectors. Retrieved from http://publications.jrc.ec.europa.eu/repository/bitstream/JRC112635/kjna29315enn.pdf