Oceanic energy resources and their potentialities on the coast zone

Critically examine the oceanic energy resources and their potentialities on the coast zone of India

India has a long coastline of about 7,517 kilometers, which stretches across nine coastal states and two union territories. This vast coast opens a great opportunity for tapping oceanic energy resources. These energy resources come from the natural movements of ocean water—waves, tides, currents—as well as the temperature differences between surface and deep waters and marine biomass. Oceanic energy is renewable, clean, and largely untapped in India.

This article will explain the different types of oceanic energy, assess their potential on India’s coast, discuss current progress, challenges, and the future of oceanic energy in India.

Types of Oceanic Energy Resources

India's oceanic energy resources can be broadly classified into the following categories:

1. Tidal Energy

Tidal energy is generated by the rise and fall of tides. When tides move in and out, large volumes of water flow in specific directions. This movement can be used to run turbines and produce electricity.

• How it Works: Dams or barrages are built across estuaries. When water flows in or out with the tide, it spins turbines to generate electricity.
• Potential in India: The Gulf of Khambhat (Gujarat), Gulf of Kutch (Gujarat), and Sundarbans (West Bengal) have strong tidal movements. These are ideal for tidal energy.
• Estimated Potential: According to the Ministry of New and Renewable Energy (MNRE), India has a potential of over 8,000 MW of tidal energy.

2. Wave Energy

Waves are formed by wind blowing over the surface of the ocean. This energy can be captured by wave energy converters.

• How it Works: Devices like buoys, floats, or oscillating water columns are installed in the sea. These move with the waves and convert motion into electrical energy.
• Potential in India: India's western coast, particularly in Kerala, Karnataka, Goa, and Maharashtra, receives strong waves, especially during the monsoon season.
• Estimated Potential: India's wave energy potential is estimated at about 40,000 MW.

3. Ocean Thermal Energy Conversion (OTEC)

This method uses the temperature difference between the warmer surface water and the colder deep seawater to generate energy.

• How it Works: Warm water from the surface is used to vaporize a working fluid, which drives a turbine. Cold water from deep sea condenses the vapor back into a liquid.
• Potential in India: The Lakshadweep and Andaman & Nicobar islands, and parts of Tamil Nadu’s coast are ideal for OTEC because of the significant temperature difference.
• Estimated Potential: India’s OTEC potential is estimated to be around 180,000 MW, especially in the tropical ocean zone.

4. Marine Biomass Energy

This involves converting marine organisms like algae and seaweed into biofuels. This can be used for power generation and fuel.

• Potential in India: India has a rich variety of marine plant species and a long coastal shelf ideal for algae cultivation.

Current Status of Ocean Energy in India

While the potential is vast, the actual use of ocean energy in India is very limited. Some efforts and pilot projects include:

• Tidal Power in Gujarat: A 3.75 MW tidal power project was planned in the Gulf of Kutch but later dropped due to high costs.
• Wave Energy Research: The Indian Institute of Technology (IIT) Madras and the National Institute of Ocean Technology (NIOT), Chennai, have developed small wave energy devices for research and demonstration.
• OTEC in Lakshadweep: NIOT set up a 100 kW floating OTEC plant near Kavaratti in Lakshadweep in 2005. It was a world-first, but not scaled up.

Overall, India is still at an early stage in developing ocean energy infrastructure.

Geographical Potential of Coastal Zones

India’s coastline can be divided into the following zones, each with its own oceanic energy potential:

1. Western Coast (Gujarat to Kerala)

• Tidal: Gulf of Khambhat and Gulf of Kutch.
• Wave: Kerala, Karnataka, Goa, Maharashtra.
• Advantages: Strong tides and waves; good for tidal and wave energy.
• Challenges: High salinity, monsoon variability, coastal erosion.

2. Eastern Coast (Tamil Nadu to West Bengal)

• Wave: Lower wave activity than west coast, but still viable in Tamil Nadu and Odisha.
• Tidal: Hooghly river estuary (West Bengal).
• Advantages: Gentle slope, steady sea conditions in Tamil Nadu.
• Challenges: Cyclones, sedimentation, ecological sensitivity.

3. Island Territories

• Lakshadweep and Andaman & Nicobar Islands
• OTEC: Large temperature gradient makes them ideal.
• Marine Biomass: Coral-rich regions support seaweed and algae farming.

Advantages of Oceanic Energy

1.Renewable: Ocean energy is a never-ending source as long as tides, waves, and sunlight exist.

2.Environmentally Friendly: It emits no greenhouse gases, helping in climate change mitigation.

3.Predictable: Tides and waves are regular and predictable, unlike solar and wind.

4.Coastal Development: Projects can boost local economies through job creation and infrastructure.

Challenges in Oceanic Energy Development

Despite the advantages, there are several challenges that India faces:

1. High Initial Cost

• Building underwater infrastructure, turbines, and barrages is very expensive.
• Many projects require foreign technology and large investments.

2. Technological Barriers

• India lacks advanced technology and expertise in ocean energy.
• Devices need to withstand harsh marine conditions.

3. Environmental Concerns

• Ocean energy projects may disturb marine ecosystems and fisheries.
• Construction in estuaries and near coral reefs must be handled carefully.

4. Lack of Policy Support

• Unlike solar and wind, ocean energy has not been given strong policy backing.
• No feed-in tariffs or incentives exist for ocean energy developers.

5. Maintenance Issues

• Sea water is corrosive and damages machinery.
• Maintenance in remote island locations is expensive and difficult.

Government Policies and Future Plans

The Government of India has started taking steps to promote ocean energy:

• Recognition as Renewable Energy: In 2019, the Ministry of New and Renewable Energy declared ocean energy as part of renewable energy.
• Research and Development: NIOT and other research institutes are being supported for technology development.
• International Cooperation: India is collaborating with countries like France and the UK for marine energy research.

The National Institute of Ocean Technology (NIOT) continues to play a key role in developing pilot projects, especially in OTEC and wave energy.

Future Potential and Way Forward

Oceanic energy could become an important part of India’s renewable energy mix in the coming decades. For this to happen, certain actions are necessary:

1.Invest in Research and Development

o   Encourage engineering institutes and private companies to develop local technology.

2.Public-Private Partnership (PPP)

o   Government and private companies should collaborate to share costs and expertise.

3.Pilot Projects and Demonstrations

o   More small-scale plants should be built to test and improve designs.

4.Policy Support

o   Provide incentives like tax cuts, subsidies, and assured buy-back of energy from ocean energy projects.

5.Protect the Marine Environment

o   Develop guidelines to avoid ecological damage during construction and operation.

India’s coastal zones have immense potential for generating clean and sustainable ocean energy. While current usage is minimal, the future is promising if proper steps are taken. Tidal, wave, and thermal energy can help reduce dependence on fossil fuels and support rural and island development. With strong government policy, technological innovation, and environmental care, ocean energy can play a key role in India's green energy future.

By tapping into the vast power of the oceans, India can take a major step toward energy security, sustainability, and coastal development.