The world’s oceans are a largely untapped resource for renewable energy. As countries strive to reduce their reliance on fossil fuels, the potential for green energy from the sea—commonly referred to as marine or ocean energy—is becoming increasingly important.
While still in its infancy compared to wind and solar power, marine energy has significant potential to play a key role in global efforts to combat climate change.
This article explores the existing and emerging technologies in marine energy, current projects, and the potential future of this exciting field.
Existing Types of Marine Energy
Several existing projects around the world are already harnessing the power of the ocean to generate renewable energy. While many are still in the testing and pilot stages, these projects provide a glimpse into the future of marine energy.
Tidal Energy:
This form of energy comes from the gravitational pull of the moon and sun, which causes tides to rise and fall. By capturing the movement of water during these tidal changes, energy can be generated.
Tidal energy is predictable and reliable, making it one of the most promising marine energy sources.
South Korea’s Sihwa Lake Tidal Power Station is the largest tidal power installation in the world, with a capacity of 254 MW.
Opened in 2011, the project uses a tidal barrage to capture the ebb and flow of tides in the Yellow Sea, near Seoul. It not only generates electricity but also helps improve water quality in the region, which has suffered from pollution.
Wave Energy:
(Source:https://www.emec.org.uk/about-us/wave-clients/pelamis-wave-power/)
Waves generated by wind blowing across the surface of the ocean are another powerful source of energy. Devices placed on the ocean’s surface can capture the up-and-down motion of the waves and convert it into electricity.
The Pelamis Wave Energy Converter was one of the first wave energy devices to be deployed commercially. Developed by Pelamis Wave Power, the system was tested in both Portugal and Scotland.
It consists of long, semi-submerged tubes that float on the surface of the sea and capture the motion of waves to generate power.
While the company that developed the technology has since ceased operations, Pelamis paved the way for future wave energy development.
Marine Current Energy:
(Source: https://inhabitat.com/atlantis-announces-funding-for-the-worlds-largest-tidal-energy-project-in-scotland/)
Similar to wind turbines, underwater turbines can harness the power of ocean currents to generate electricity. These currents are typically more consistent than winds, making marine current energy an attractive option for reliable power generation.
The MeyGen project in Scotland is the world’s largest tidal stream energy site. Located in the Pentland Firth, between mainland Scotland and the Orkney Islands, MeyGen began generating electricity in 2016.
The project is using underwater turbines to harness the powerful tidal currents that pass through the strait. In its first phase, MeyGen installed four turbines with a combined capacity of 6 MW, and the project plans to expand to 398 MW, providing clean energy for up to 175,000 homes.
Companies like Orbital Marine Power are developing floating tidal platforms with larger turbines that are expected to generate more energy at lower costs.
Future Types of Marine Energy
The true potential of marine energy lies in the future. New technologies and projects are in the pipeline, each offering innovative solutions to the challenges facing marine energy development.
Ocean Thermal Energy Conversion (OTEC):
The temperature difference between warmer surface water and colder deep water in tropical regions can be harnessed to generate electricity.
OTEC systems use this thermal gradient to drive a heat engine, which in turn produces power.
Salinity Gradient Energy:
This is a more experimental form of ocean energy that takes advantage of the difference in salt concentration between seawater and freshwater at river mouths.
This process can generate energy through osmosis, a method still under development.
Hybrid systems:
Combining wind and wave energy generation on a single platform is another promising development.
Hybrid systems are particularly appealing because they can generate power from both the wind and ocean waves, maximizing energy production and reducing the cost of installation.
Projects like W2 Power are experimenting with combining wind turbines and wave energy converters in a single offshore installation.
Challenges Facing Marine Energy
Despite the promising developments in marine energy, the sector faces significant challenges. The ocean is a harsh environment, and the infrastructure needed to harness energy from the sea must withstand powerful storms, corrosion, and marine life.
High upfront costs and long development timelines are also barriers to widespread adoption. Another challenge is the environmental impact. Although marine energy is considered a green technology, it can still affect marine ecosystems.
Tidal barrages, for example, can disrupt the migration of fish and other aquatic life. Developers must carefully design projects to minimize these impacts and work with environmental agencies to ensure sustainability.
The Future of Marine Energy
The future of marine energy looks promising, especially as the technology becomes more efficient and cost-effective. According to the International Energy Agency (IEA), marine energy could provide up to 10% of the world’s electricity by 2050.
Countries with extensive coastlines, such as the UK, Canada, and Norway, are well-positioned to benefit from this growing industry.
Moreover, as the world continues to transition to renewable energy, marine energy offers a consistent and predictable source of power that complements other renewable sources like solar and wind.
With continued research, investment, and international cooperation, marine energy could play a crucial role in achieving global climate goals.
Conclusion
Green energy from the sea holds immense potential for the future. Existing projects, such as tidal power stations and wave energy converters, have demonstrated the feasibility of marine energy.
Emerging technologies, including floating platforms and hybrid systems, offer exciting possibilities for expanding this form of renewable energy.
While challenges remain, marine energy is set to become an important part of the world’s clean energy mix, helping to reduce reliance on fossil fuels and combat climate change in the coming decades.
