What is ocean energy?
Ocean energy refers to all forms of renewable energy derived from the sea. There are three main types of ocean energy technology: wave, tidal and ocean thermal.
All forms of ocean energy are still at an early stage of commercialisation. Wave energy remains more costly than the other ocean energy technologies. Tidal range (see explanation below) has been deployed in locations globally where there is a strong tidal resource (for example La Rance in France, Sihwa in South Korea), while tidal stream (see below) has been demonstrated at pilot scale.
How does it work?
Wave energy is generated by converting the energy within ocean waves (swells) into electricity. There are many different wave energy technologies being developed and trialled to convert wave energy into electricity.
Tidal energy comes in two forms, both of which generate electricity:
- Tidal range technologies harvest the potential energy created by the height difference between high and low tides. Barrages (dams) harvest tidal energy from different ranges.
- Tidal stream (or current) technologies capture the kinetic energy of currents flowing in and out of tidal areas (such as seashores).Tidal stream devices operate in arrays, similar to wind turbines.
Ocean thermal energy is generated by converting the temperature difference between the ocean’s surface water and deeper water into energy. Ocean thermal energy conversion (OTEC) plants may be land-based as well as floating or grazing.
ARENA’s purpose is to accelerate Australia’s shift to affordable and reliable renewable energy. By connecting investment, knowledge and people to deliver energy innovation, we are helping to build the foundation of a renewable energy ecosystem in Australia.
Marine energy technologies could play a role in the medium term, for example to provide energy to aquaculture projects or help protect breakwaters.
Australia has a number of innovative technologies in both wave and tidal energy; however, the main challenges are capital cost and withstanding damage from harsh ocean conditions. Project financing is a major global challenge for wave projects and for tidal energy, environmental impact can also be a significant barrier for use.
ARENA has provided funding support for 14 ocean projects. ARENA also works with the ocean energy industry, sharing lessons from our wave energy projects and supporting activity to advance the sector through R&D and demonstration projects. This will enable potential investors to identify sites for further investigation, and policymakers to have better information regarding the potential for ocean energy to contribute to Australia’s energy mix.
ARENA shares knowledge, insights and data from our funded projects to help the renewable energy industry and other projects learn from each other’s experiences. Our projects capture high-quality quantitative and qualitative data and information, linked with the needs of the market, while respecting our recipients’ commercial and contractual rights.
Reports from our ocean energy projects can be found in the ARENA Knowledge Bank.
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