I read an article last week on a subject that I admittedly know very little about: tidal power. I’ve seen a few videos on Youtube about the subject, but that’s about it. What is tidal power? Is tidal power a reliable, consistent renewable energy? With so much of the world’s population living near large bodies of water, why isn’t tidal power a rival to solar or wind as a viable source of renewable energy? Let’s take a look at the good and bad.


Tidal power is defined as a method of energy generation that relies on the variations of ocean tides and currents. Power is created as the tides rise and fall, a completely natural process. Although fossil fuels are burned when the turbines used to create the energy, tidal power is 100% renewable otherwise. Energy can only be created where there is a significant difference between low and high tides. As of the date of this writing, the largest operating tidal energy facility in operation is the Sihwa Lake Tidal Power Station located in South Korea’s Gyeonggi Province.


Generating power from the shifting tides is possibly the most environmentally-friendly method of energy creation. Tidal power produces zero emissions of any kind, and the equipment used does not alter the natural behaviors of the ocean.  Unlike weather patterns, wave patterns are predictable and easily tracked. This makes tidal power a much more reliable source of renewable energy than both wind and solar. Tidal energy plants are also very cheap to operate. After installation costs are factored in, energy created from the ocean can cost a mere $0.02 per kW hour. It doesn’t get much cheaper than that! There is also huge potential for energy generation. According to the United States Department of Energy (DoE), tidal and wave energy could potentially create approximately 1,400 Terawatt hours (TWh) per year. With an annual requirement of nearly 4,000 TWh, the addition of tidal energy to our power grid could have a major positive impact.


Building tidal energy facilities on a large scale may have unintended consequences. While current tidal power stations do not have a negative effect on their environments, it is unknown what adding additional facilities will do to marine life or beach quality. Tidal energy plants are also limited in where they can be placed. Facilities must be close to land so that the electricity produced can be easily transferred to the power company’s main grid. They must also be placed in locations with tidal energies dynamic enough to generate power. A recent study conducted by the U.S. Department of Energy (DoE) and scientists at Georgia Tech University concluded that there are only a handful of sites in the U.S. that meet this criteria. Tidal energy plants are also extremely expensive to build. The technology used in the process is relatively new, and major strides in design and construction are needed before tidal energy can be harnessed on a grand scale.

What do our readers think of tidal power and its potential? Will we one day generate all of our power from the sea or will wind and solar remain the undisputed leaders in renewables? Please leave us a comment below and let us know.

Source | Images: Wikimedia Commons