Marine Renewable Energy: The Future of Clean Energy
As the world is moving towards cleaner energy sources, marine renewable energy has emerged as a promising alternative to traditional fossil fuels. With oceans covering about 70% of the earth’s surface and more than 80% of its volume, Marine Renewable Energy Sources (MRES) hold immense potential to generate clean and sustainable energy.
Marine renewable energy technologies are still in their early stages, but they have made significant progress over the past few years. In this article, we will explore some of the most promising MRES technologies that could help us transition away from fossil fuels.
1. Tidal Power
Tidal power is one of the most well-known forms of MRES technology. It involves harnessing the power generated by ocean tides to produce electricity. Tidal turbines are installed underwater in areas where there is strong tidal flow, such as estuaries or narrow straits between islands.
The UK has been at the forefront of developing tidal power technology with several projects underway around its coastline. The largest project planned for deployment is MeyGen in Scotland which aims to deploy up to 269 turbines by 2023 with an installed capacity of up to 398MW.
2. Wave Energy
Wave energy refers to capturing kinetic energy from ocean waves and converting it into electrical power using wave generators or buoys that move up and down with wave motion.
One company working on wave energy technology is Carnegie Clean Energy based in Australia which recently completed a world-first grid-connected wave-energy plant off Western Australia’s coast near Garden Island Naval Base.The facility consists of three CETO-6 units anchored below sea level that operate under water pressure cycles caused by passing waves.The system generates electricity through hydroelectricity conversion when high-pressure water drives submerged pumps which drive hydraulic motors linked directly to utility-scale generators onshore.Because CETO-6 operates under water it avoids corrosion problems associated with salt spray and can be used in deep water.
3. Ocean Thermal Energy Conversion (OTEC)
Ocean Thermal Energy Conversion (OTEC) is a process that involves harnessing the temperature differences between warm surface water and cold deep water to generate electricity. OTEC technology relies on a heat engine, which uses the temperature difference to drive turbines that produce electricity.
The potential of this technology is enormous, as it could provide energy to remote island communities or coastal cities with access to deep ocean waters. As yet there are no commercial scale OTEC plants operating anywhere in the world but several small-scale demonstration projects have been carried out over recent years.
4. Salinity Gradient Power
Salinity gradient power, also known as osmotic power, refers to generating electricity from the difference in salt concentration between freshwater and seawater using membranes.The concept of salinity gradient power has been around for decades; however, until recently membrane technology was not advanced enough for commercial application.
Norwegian company Statkraft opened its prototype osmotic power plant in 2009, however it was closed down after two years due to high operational costs.Today there are several companies actively developing and testing new technologies for salinity gradient power including Dutch firm REDstack who are building on their pilot project with a new installation planned off Texel Island by 2022.
5. Floating Wind Turbines
Wind turbines have become one of the most popular forms of renewable energy generation worldwide; however, they need stable foundations on land or shallow waters.Floating wind turbines allow us to install them offshore where winds are stronger and more consistent than on land – providing clean energy without taking up valuable real estate.Online retailer Amazon announced last year that it would invest $10bn (£7.7bn) into “moonshot” research & development programs aimed at achieving net-zero carbon emissions by 2040.One area earmarked for investment is floating offshore wind farms.A recent report by the Offshore Renewable Energy Catapult (OREC) estimates that floating offshore wind turbines could generate up to 17% of the UK’s electricity demand.
Conclusion
In summary, marine renewable energy sources offer an enormous potential for clean energy generation. These technologies are still in their early stages, but with research and development they have the capacity to revolutionise our approach to energy generation.
Whilst some MRES technologies remain prohibitively expensive for mass deployment, others such as wave power and floating wind turbines can already compete with traditional fossil fuels in certain locations. As investment increases and technology advances further we can expect more projects around the world which will help us transition away from non-renewable sources of energy toward a cleaner, sustainable future.