Tidal energy

Tidal energy is a form of power produced by the natural rise and fall of tides caused by the gravitational interaction between earth, the sun, and the moon. Tidal currents with sufficient energy for harvesting occur when water passes through a constriction, causing the water to move faster. Using specially engineered generators in suitable locations, tidal energy can be converted into useful forms of power, including electricity. Other forms of energy can also be generated from the ocean, including waves, persistent ocean currents, and the differences in temperature and salinity in seawater.

Suitable locations for capturing tidal energy include those with large differences in tidal range, which is the difference between high tide and low tides, and where tidal channels and waterways become smaller and tidal currents become stronger.

As worldwide demand for clean electricity, renewable fuels, and critical materials for energy and industrial processes grows, it is crucial to identify and secure sustainable energy resources beyond what is currently available. Researchers recognize the vast potential of the ocean to produce reliable, renewable energy for a variety of uses. The Water Power Technologies Office of the Department of Energy (DOE) estimates that energy from waves, tides, and ocean currents have the combined potential to generate enough electricity to power millions of homes.

Because water is denser than air, tidal energy is more powerful than wind energy, producing exponentially more power at the same turbine diameter and rotor speed. Tidal power is also more predictable and consistent than wind or solar energy, both of which are intermittent and less predictable. This makes tidal energy an intriguing renewable energy source to pursue. The challenge is in making it commercially feasible to capture and convert the energy into usable power at scale, as well as finding uses of tidal energy where costs are less sensitive than national grid electricity.

To fully harness tidal energy as a significant and ongoing source of clean energy, it is critical that researchers explore ways to assist in developing technologies and methods that increase its viability for broad commercial application. The industry is largely just emerging, with complex barriers to overcome before it can sustainably grow and thrive.

Tidal energy represents a significant opportunity to increase the world’s renewable power generation capacity. As countries continue to develop, and the global population and its reliance on energy grows, so does the demand on power systems to provide additional clean energy resources. Tidal energy could potentially supply a significant percentage of future electricity needs if barriers, including robustness of devices, environmental challenges, and the cost-effectiveness of its commercial application, can be successfully navigated. Tidal energy is a clean, renewable, sustainable resource that is underutilized and represents significant opportunity to meet growing global energy needs, both now and in the future. Water is hundreds of times denser than air, which makes tidal energy more powerful than wind. It is more efficient than wind or solar energy due to its relative density and produces no greenhouse gases or other waste, making it an attractive renewable energy source to pursue.

Pacific Northwest