The source of wind energy is solar heating. The sun heats the earth's surface unequally. The heat gathered by land masses and large bodies of water is also released, thereby warming the air above them. However, water does not heat up as quickly as land. Because water has a higher heat capacity than land, it requires more incoming solar radiation to heat a body of water to the same degree as it does to heat a land mass. Water also releases its heat less readily than land. As a result, in response to solar heating the air over large bodies of water typically remains cooler than the air over continental land masses.

Along the coast, sea breezes form when the light, heated air over land masses rises and the heavy, cool air over the ocean moves onshore to replace it. At night, when the land cools, also cooling the air above it, the process is reversed. The warmer air over the ocean rises, allowing the cooler air over the land to move offshore to replace it, creating a breeze going out to sea.