Home > Statistic of the Week > Archive List > Detail

<< Prev 2/20/2011 Next >>

Surfing Math Equations


The world is constantly searching for more sources of energy, and at reduced cost. Could it be that our next source of power might be the next 25-foot wave about to hit shore.

The key equation is P = [dg2TH2L]/[32π], where

  • P = Power of wave in deep water, measured in watts
  • d = Sensity of water (1025 kg/m3)
  • g = Acceleration due to gravity (9.81 m/s2)
  • T = Period of wave in seconds (i.e. time between two successive peaks)
  • H = Height of wave in meters (i.e. distance from trough to peak)
  • L = Length of wave in meters (i.e. perpendicular to direction of travel)
Now, some helpful data. Swells of waves off the Pacific Coast average 6 feet in height and are 10 seconds apart in timing.

Two claims have been made....are they true...

  1. If the wave energy in all waters on US coasts could be converted into power, it would satisfy half of the nation's demand for electricity
  2. Bigger, less frequent waves contain more power

Source: Julie Rehmeyer's "Sea Power," Wired, September 2010, p. 51