The Great Potential Of Tidal Energy

By Haley Zaremba - May 12, 2023

• The potential of tidal energy is huge, but the U.S. currently doesn’t have a single tidal power plant operational.
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• the total energy potential of marine sources is estimated to be more than double (57%) the amount of energy currently being produced in the country each year.
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• Breakthroughs in tidal energy will almost certainly be piecemeal and low-impact, but tidal energy eventually could become a larger part of the renewables puzzle

As the world begins to feel the urgency of the decarbonization imperative, more investing dollars and public support are available than ever before for renewable energy research and development. As a result, even some of the most futuristic and far-fetched ideas are getting real backing – with real results. Already, technologies that feel ripped out of the pages of science fiction are being proven feasible – from creating an artificial sun here on Earth, to beaming solar power straight from the stars to our own energy grids. But it turns out that space is not the only final frontier for clean energy extraction – and the other one is a lot closer to home. 

Looking to the ocean to solve some of our biggest global crises is not a new idea. Seawater – a vast and seemingly inexhaustible resource – has been a source of hope and experimentation for extracting everything from fresh drinking water in the face of a mounting water crisis to creating limitless green hydrogen to replace industrial fuels. The constant motion of the ocean through waves and tides has also been viewed as a potential source of renewable energy, but scaling tidal energy in a practical and affordable way has remained elusive. But the promise and allure of harnessing the full potential of tidal energy is so great that scientists and researchers around the world have persisted in finding a way to do it. In the United States alone, the total energy potential of marine sources is estimated to be more than double (57%) the amount of energy currently being produced in the country each year. These findings came from a groundbreaking report from the National Renewable Energy Laboratory (NREL) released in 2021. The numbers released by NREL are particularly flooring when you consider that the United States has particularly low tidal energy potential compared to other countries. 

That’s why the United States has no tidal plants, while other countries including South Korea and France have had tidal plants online for years now. But that may not be the case for long. For one thing, there is currently unprecedented government support for exploring marine energy sources in the United States. he Biden administration has given special attention through the promise of marine energy sources through its Ocean Climate Action Plan, which notes the potential of offshore wind power as well as sourcing renewable energy from ‘less-explored sources’ such as waves, tides and currents. 

These three phenomena – waves, tides, and currents – present numerous different methods of potential energy production. Each is suited to different parts of the coast and ocean where the waters behave differently, allowing for more ways to create marine energy in more places. But each also presents certain challenges for achieving efficient and scalable energy production. Waves certainly pack a wallop, but they’re unsteady and still quite unpredictable despite scientists’ best modeling efforts, which makes machine design for wave energy extremely difficult. Tides are far more predictable, which is why tidal energy is way further along its own R&D trajectory. However, tidal energy is only feasible in very specific conditions that don’t exist in very many places on Earth. Currents, too, are predictable and constant, but scientists worry that harvesting too much of that energy could alter important oceanic patterns that regulate the climate, ultimately making matters worse.

While none of these energies provides a silver bullet solution, scientists are constantly working to refine and improve their methods in the hope that one day, one of these technologies could make a real impact. One example is a groundbreaking wave power project called PacWave, currently underway off of the Oregon coast. According to recent reporting from CNET, the ‘ambitious’ project is “an offshore experimental testbed built to develop and demonstrate new technology that converts the power of waves into onshore electricity.” Seven miles of conduit have already been laid between the testbed out in the Pacific and the Oregon coast using “pioneering horizontal drilling techniques.” The project could be fully operational as soon as 2025, when it would have an energy production capacity of 20 megawatts. This isn’t enough to revolutionize the energy sector by any means, but it will be able to provide a few thousand homes with clean and renewable energy. 

This is likely indicative of the trajectory of marine power on the whole. Breakthroughs will almost certainly be piecemeal and low-impact, but hopefully they will snowball into what is eventually a robust energy alternative. It likely will never provide a silver-bullet solution to fix the energy sector and the climate, but it’s one more piece of a diverse clean energy puzzle that is slowly but surely developing strong enough technologies to replace fossil fuels over time. And that’s a good thing. A diverse energy mix is a resilient energy mix. Relying too much on any one energy source is a very dangerous game. In this sense, a little bit of tidal, a little bit of wave energy, and a little bit of current energy could go a very long way. 

By Haley Zaremba for Oilprice.com