Harnessing the Power of Tides: A Predictable Path to Renewable Energy

The world is abundant with natural resources as well as big ideas on how to preserve them.

As we collectively pivot toward a more sustainable future, renewable energy has become more than just a choice; it’s a necessity. Among the many sources of green energy, tidal power stands out due to one simple fact: tides are predictable.

Unlike wind or solar energy, which can fluctuate daily, tidal cycles follow the moon and sun with almost clockwork precision — making them a reliable and sustainable source of electricity.

It’s fascinating how human innovation continuously finds ways to tap into nature’s rhythm. Today, tides, created by the gravitational pull of the moon and the sun, are being harnessed in various ways to generate electricity. Both tidal range (the vertical difference between high and low tide) and tidal stream (the horizontal flow of water) are being utilised through ingenious engineering to produce consistent and clean power.

Oceanographer Simon Neill emphasizes that for a location to be viable for tidal range energy, the tidal difference should ideally be a minimum of 5 meters. One of the most remarkable natural examples is the Bay of Fundy in Canada, which boasts the highest tidal range in the world—close to 12 meters. In contrast, Sri Lanka’s tidal range is less than 1 meter, making it less suitable for such developments, yet offering opportunities to study other marine-based renewable solutions.

What’s inspiring is how every corner of the globe is exploring its own strengths in the natural world to contribute to a greener planet.

How Are Global Tidal Energy Projects Progressing?

Countries like Canada, the United Kingdom, France, South Korea, and China are leading the way with major tidal energy projects.

• Tidal Lagoon Swansea Bay project: The Swansea Bay Tidal Lagoon project was a proposed 320MW tidal power plant planned for Swansea Bay, Wales, aiming to become the world's first tidal lagoon. The project's goal was to generate reliable, zero-carbon electricity for 120 years, enough to power 155,000 homes.

• MeyGen Project (Scotland): One of the world's largest tidal stream projects, aiming to eventually power 175,000 homes.

• Sihwa Lake Tidal Power Station (South Korea): Currently, the world's largest tidal range power station.

• La Rance Tidal Power Plant (France): Operational since 1966, showing that tidal energy can work reliably for decades.

• Nova Innovation (Canada and Scotland): Pioneering small-scale tidal turbines that are installed under the sea, producing clean energy without massive infrastructure.

These projects are proving that tidal energy can be a crucial part of the future renewable energy mix — especially for coastal nations.

Impact on Marine Life — And How to Mitigate It

While the promise of tidal energy is exciting, it’s critical to consider the environmental impacts, particularly on marine ecosystems. Potential concerns include:

• Habitat Alteration: Tidal barrages (or dams) can alter water flow patterns, sediment transport, and tidal ranges, affecting habitats and species that rely on these conditions.

• Fish and marine mammal collisions: Moving turbines pose a risk to wildlife.

• Fish Migration: Tidal barrages can impede the movement of migratory fish, disrupting their breeding cycles and potentially impacting fish populations.

• Noise pollution: Underwater noise from machinery could disturb marine life.

Mitigation Strategies:

• Careful site selection to avoid ecologically sensitive areas.

• Design improvements like slower-moving, fish-friendly turbines.

• Real-time monitoring of marine animals using sonar and acoustic tracking.

• Fish Passages: Construct fish ladders or other passages to allow fish to bypass barrages and continue their migrations

• Environmental Monitoring: Conduct thorough environmental monitoring to track the effects of tidal energy developments on marine life and make adjustments as needed. .

By integrating sustainable practices from the start, tidal energy projects can balance clean energy generation with marine conservation.

A Final Thought...

Tapping into the power of tides shows the incredible creativity of humanity in working with nature, not against it. Every corner of the globe is discovering its unique strengths to contribute to a greener future.

To learn more about the incredible potential of tidal energy, I highly recommend this video produced by Deutsche Welle:

Tidal Energy: Is it time to harness the power of the oceans?

Let’s keep pushing boundaries...