In most cases ocean waves are caused by winds blowing over the sea. Waves transmit a lot of energy across the ocean, the energy value can be found by using wave power formula for the wave energy flux, Watt per meter of crest length:

P = ρ*g^{2}*T*H^{2}/(64*π), [W/m] [1]

where

H - the vertical distance between crest and trough of the wave, meters;

T - the period of wave, seconds;

g - the acceleration of gravity, m/s^{2};

ρ - the mass density of sea water, kg/m^{3};

π - 3.14159

The wave energy per square meter can be calculated using this formula:

E = ρ*g*H^{2}/16, [J/m^{2}] [2]

Both formulas are correct for depth more than half the wavelength.

Source: A review of wave-energy extraction by Johannes Falnes, Marine Structures 20 (2007) 185 – 201