The
World Energy Council has estimated that approximately 2
terawatts (2 million megawatts), about double
current world electricity production, could be produced from the oceans
via wave power.
The United States uses about 4,000 terawatt hours (TWh) of electricity per year. DOE estimates that the maximum theoretical electric generation that could be produced from waves and tidal currents is approximately 1,420 TWh per year, approximately one-third of the nation's total annual electricity usage.
calculate the maximum kinetic energy available from waves and tides off U.S. coasts that could be used for future energy production, and which represent largely untapped opportunities for renewable energy development in the United States.
The West Coast, including Alaska and Hawaii, has especially high potential for wave energy development, while significant opportunities for wave energy also exist along the East Coast. Additionally, parts of both the West and East Coasts have strong tides that could be tapped to produce energy.
‘Pelamis’ wave energy conversion devices and generates a combined 2.25 MW of electricity. OPD plans to expand the facility to produce 22.5 MW in 2007
The United States receives 2,100 terawatt-hours of incident wave energy along its coastlines each year, and tapping just one quarter of this potential could produce as much energy as the entire U.S. hydropower system.
Total Annual U.S. Incident Wave Energy
2,110
terrawatt-hours
Wave energy is generally affected by three main factors:
Wind speed - higher wind speed means more wave energy, because the energy is transfered from the wind to the wave.
Fetch - the distance of open water over which the wave has travelled across makes a big differenece on wave height and wave energy, as a longer fetch gives the waves longer to 'grow'.
Wind duration - with a longer storm, the waves will be bigger.
"Worldwide, approximately 3000 gigawatts (1 gigawatt = 1 GW = 1 billion watts) of energy is continuously available from the action of tides.
The best areas are on the eastern sides of the oceans (western side of the continents) between the 40 and 60 latitudes in both the northern and southern hemispheres.
While the "wave power at deep ocean sites is three to eight times the wave power at adjacent coastal sites," constructing and mooring the site and transmitting the electricity to shore would be prohibitively costly.