Wave energy, in one sense, is just another form of solar energy. This might sound odd, but just consider that waves start from wind, which forms as a result of the sun's heating of the Earth.The sun doesn't ever heat the Earth evenly. Depending on the Earth's natural formations as well as its orientation to the sun, some spots get heated more than others. As some air gets heated, it becomes less dense, and thus lighter, and naturally floats upward. This leaves an open space for denser, colder air to rush in and take its place. This air rush is the refreshing cool breeze you feel on a sunny day.Wind is also responsible for our very powerful waves. As wind rushes up along the water, the friction causes ripples. Wind continues to push against these ripples in a snowball effect that eventually creates a large wave. Essentially, this action is a transfer of energy from the sun to the wind to the waves.
Waves vs. TidesAlthough wind causes the powerful surface waves that we use for wave energy, the moon's gravitational pull is responsible for the tides, which is the rise and fall of the oceans twice a day. Tidal energy, distinct from wave energy, also holds energy potential. It could contribute about 3 percent to the U.S.'s energy needs, and more for the U.K. [source: Holzman]. "Tidal wave" is a misleading term and has to do with an underwater disturbance rather than tides.
