ncy to mitigate climate change intensifies in 2025, clean energy sources aren’t optional anymore—those times are gone. Among them, tidal energy or tidal power is characterized by its reliability, predictability, and minimal environment impact. Compared with the sun and wind power, which are unstable and unpredictable, tidal energy is a reliable, long-term opportunity for island and coastal nations to become independent and carbon-neutral.
What Is Tidal Energy?
Tidal energy is a form of hydropower that uses the natural oscillation of ocean tides as electricity. Ocean tides are generated by the gravitational interaction of Earth, Moon, and Sun. When seawater comes in and goes out with the tides, the kinetic and potential energy of the seawater can be converted with turbines or some other apparatus for conversion.
In 2025, tidal power is increasingly being viewed as a critical component of the renewable mix thanks to recent technological breakthroughs and policy efforts in the EU, China, South Korea, and Canada.
Historical Background
People have been using tidal currents since ancient times. Roman engineers, for example, powered tide mills to mill grain and shift heavy weights. Such mills stored water during high tide and let it flow through water wheels during low tide. Though primitive, such schemes laid the ground for today’s advanced tidal power plants.
The La Rance Tidal Power Station in France, commissioned in 1967, was the world’s first large tidal power plant. Its capacity is 240 MW (upgraded to about 250 MW after renovation), and it is still operational today, supplying thousands of homes with clean energy.
How Does Tidal Energy Work?
As of 2025, the three dominant types of tidal energy technologies are:
- Tidal Barrages
These are dam-like structures built over estuaries. Water is stored in a reservoir during high tide and released through turbines in low tide to generate electricity. This works well but requires tremendous initial investment and exact environmental planning.
- Tidal Stream Generators
These tidal turbines function like wind turbines, with horizontal tidal current motion turning blades and generating power. They are less invasive than barrages and can be used across a variety of marine environments.
- Tidal Lagoons
Tidal lagoons are experimentally under development, surrounding bodies of coastal water, generating electricity on the same principle as barrages but with more flexibility in the choice of location.
Recent Developments in 2025
As of 2025, global tidal power capacity is in excess of 1.5 GW, with installation in operation or pilot schemes ongoing in the following countries:
United Kingdom: Scotland’s MeyGen project remains the largest tidal stream project in Europe. It completed its Phase 3 development during the last year, expanding capacity to over 100 MW.
South Korea: South Korea’s Sihwa Lake Tidal Power Station (254 MW) continues to lead Asia’s market, with new developments in Garolim Bay.
Canada: Bay of Fundy in Nova Scotia has one of the largest tidal ranges on the globe. The site now boasts several commercial tidal stream units installed.
China: China continues to invest in over 100 small-scale tidal farms, particularly in Zhejiang and Fujian provinces.
France: La Rance was retrofitted to include smart grid capability and remains a global example of success.
In addition, developing countries such as Indonesia, the Philippines, and Chile are even actively seeking tidal resources as part of their national clean energy strategies.
Advantages of Tidal Energy
A number of special advantages make tidal energy exceptional compared to other renewables:
✅ Predictability: Tides follow predictable lunar cycles, enabling accurate forecasts years in advance.
✅ Longevity: Power stations can last 75–100 years—far longer than wind or solar farms.
✅ High Energy Density: Water is 800 times denser than air, which means tidal turbines are more efficient in smaller locations.
✅ Low Emissions: After installation, tidal power stations release virtually no greenhouse gases.
✅ Grid Stability: Its predictability increases the stability of the grid relative to intermittent renewables like wind and solar.
Environmental and Economic Considerations
While tidal power is green, it has its drawbacks. Uninhabited development of barrages and lagoons can affect estuarine systems, fish migrations, and sediment transport. On a positive note, existing environmental impact assessments and mitigation technologies are reducing these risks significantly.
Economically, the price of tidal energy electricity has fallen from over $0.50 per kWh in 2000 to under $0.20 per kWh in 2025 because of modular turbine design, predictive maintenance through AI, and economies of scale.
Future Outlook
The International Energy Agency (IEA) estimates tidal power could meet up to 3% of global electricity demand by 2040 if trends continue. That doesn’t sound like much, but for countries with long coastlines and significant tidal ranges, it can be a game-changer.
Hybrid energy systems—tide plus offshore wind and floating solar—are already pilot projects in the Netherlands and South Korea.
In addition, reintroducing modern tide mills to peripheral or developing communities could provide low-cost, decentralized energy supply with minimal environmental effects.
Conclusion
In 2025, tidal energy is one of the most promising, untapped sources of clean power. From ancient tide mills to sophisticated underwater turbines, humankind’s relationship with the ocean continues to evolve. As the world grapples with the double menace of climate change and growing energy needs, investment in clean, safe, and reliable sources like tidal energy is not just wise but also essential.
