Title: Ocean Energy
1Ocean Energy
Kim Cobb with slides from Dr. Alam, MIT
2Overview of Ocean Energy
- ocean energy is replenished by the sun and
through tidal influences of the - moons and suns gravitational forces
- near-surface winds induce wave action and cause
wind-blown currents at - about 3 of the wind speed
- tides cause strong currents into and out of
coastal basins and rivers - ocean surface heating by some 70 of the incoming
sunlight adds to the - surface water thermal energy, causing expansion
and flow - wind energy is stronger over the ocean due to
less drag, although - technically, only seabreezes are from ocean
energy
3How much energy and what types?
- 250 Billion barrels of oil worth of energy coming
into ocean every day - 80 million barrels of oil per day produced
kinetic
potential
4How much energy and what types?
- 250 Billion barrels of oil worth of energy coming
into ocean every day - 80 million barrels of oil per day produced
Theoretical global resource of ocean
energy 8,000-80,000 TWh/yr for wave energy 800
TWh/yr for tidal current energy 2,000 TWh/yr for
salinity gradient energy 10,000 TWh/yr for ocean
thermal energy
Worlds electricity consumption 17,000 TWh/yr
5Source of Ocean Wave Energy
6(No Transcript)
7Wave Energy Extraction Technologies
Oscillating Water Column (Energetech/Oceanlinx)
- Point
- Absorber
- (OPT,
- Finavera)
Overtopping, Wave Dragon
Attenuator, Pelamis WP
8Power From Ocean Waves
kW/m crest length
9Power From Ocean Waves
- Wave energy is strongest on the west coasts and
increases toward the poles. - At approx. 30 kW/mcl in the Northwest (yearly
avg.), a single meter (3.3 feet) of wave has the
raw energy to power about 23 homes.
10Point absorber buoys most common
11(No Transcript)
12Oscillating Water Column Installations LAND
NOTE Plant Bowen (Georgia Power) operates at
3,200,000 kW
13Oscillating Water Column Installations OCEAN
14Overtopping Wave Energy
15Sea Snake Wave Energy
121m long, 3.5m tall!
16(No Transcript)
17Tidal Energy Conversion
18Ocean Thermal Energy Conversion
19210 kW OTEC test plant, 1993-1998, Hawaii
20Future OTEC plant grow food and fuel?
21Ocean Energy Where are we today?
- Wave Energy (grid-connected)
- 0.4MW and 0.5MW OWC off the coast of Pico and
Islay by 2008 - 2.25MW Pelamis off Portugal by 2008
- 0.5MW section of Wave Star Energy off Denmark by
2009 - 7MW Wave Dragon off Wales by 2010
- Tidal
- barriers 240MW France in 1966 and 20MW in
Canada - Current 1.2MW off Ireland by 2009, 1MW France
- Thermal
- 0.2MW Hawaii 1993-1998
22Ocean Energy PROS and CONS?