Microsoft Word Report 11 02 Wave Power final ex appendix doc

part is now continued in the Swedish 
BOWEC project.
Company
Seabased
Ocean Harvesting 
Technologies
Bohegg 
Engineering
AW Energy
Langlee Wave 
Power
Fred Olsen
Wave Energy
Pelagic Power
DEXAWAVE
Wave Dragon
WavePlane
Wave Star 
Energy
Floating Power 
Plant
Pelamis Wave 
Power
Aquamarine 
power
Wavebob
Ocean Power 
Technologies Ltd
Wavegen
Oceanlinx
Carnegie Wave 
Energy
Name
Seabased WEC
Ocean 
Harvester
Bowec
WaveRoller
Langlee E2
Bolt
Sea-wave Slot-
cone Generator
- SSG
W2-POWER
DEXAWAVE 
converter
Wave Dragon
WavePlane
Wave Star
Floating Power 
Plant
P2
Oyster 
Wavebob
Power Buoy
Wavegen nears-
hore OWC
Oceanlinx Mk3
CETO
Type
Point absorber
Point absorber
Point absorber
Oscillating wave 
surge converter 
Oscillating wave 
surge converter
Point absorber
Overtopping
Hybrid wave & 
wind power plant
Attenuator
Overtopping
Overtopping
Multi point 
absorber
Hybrid wave & 
wind power plant
Attenuator
Oscillating wave 
surge converter
Point absorber
Point absorber
Oscillating water 
column 
Oscillating water 
column 
Other
Stage
Full-scale 
Demonstration
1:20 scale tank 
testing
Unknown
Demonstration
1:20 scale tank 
testing
Real sea test
1:4 scale 
turbine tests
1:3 scale tests of 
wave PTO
1:10 scale in real sea
1:4.5 scale in real 
sea
Interrupted full-scale 
test 
Section of WEC 
tested in real sea
Wave part tested in 
scale in real sea
Commercial sales
Full-scale demon-
strator 
1:4 scale in real sea
A 40 kW version 
has been tested in 
real sea
500 kW land based 
machine on Islay
Pre-commercial Mk3 
deployed in Feb 
2010
200 kW demon-
stration under 
construction
Capacity (full-scale)
~ 30-50 kW
100+ kW
Unknown
Unknown, 300 kW
prototype planned
400 kW
45 kW
Unknown
Unknown
250 kW
~ 10 MW
Unknown
Up to 6 MW
Multi MW
750 kW
2,5 MW for three devices 
and one PTO
1-1,5 MW
150 kW under con
struction, 500 kW being 
designed
Individual turbines up to 
100 kW
>2.5 MW
Unknown, several units 
connect to one PTO
Country

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WAVE POWER
ELFORSK
Technology type

Attenuator

Point Absorber
Oscillating Surge
Wave Converter
Oscillating Water 
Column
Overtopping Devise
Submerged Pressure 
Differential
Other
All
Working principle
Attenuators are often hinged multi body devices where different parts of the device 
experiences different phases of a wave. The reaction force is a buoyancy- vs. buoy-
ancy force derived from the phase difference.
Point absorbers can look very different, but common is that they consists of two sepa-
rate systems. One system usually riders the wave whilst the other supplies a reference 
to react against. The reference is in some cases a fixed point i.e. the seabed and 
in other cases inertia. The reaction force is either derived from buoyancy vs. fixed 
reference or buoyancy vs. inertia.
An OSWC is typically a hinged flap type device standing on the bottom rather close 
to shore. In the nearshore the otherwise circular water particle orbit becomes el-
liptical and this horizontal wave motion component (surge) is utilised to move a flap 
back and forth.
An OWC uses an air chamber in which a water column oscillates up and down as 
the device interacts with the waves. This causes air to be pushed and pulled in and 
out of the air chamber and through a bidirectional air turbine.
An overtopping device consists of three main parts – a collector, a reservoir, and a 
PTO. The collector is wider at the wave inlet and narrower at the reservoir – causing 
the waves to grow vertically. The waves overtop into the reservoir at the end of the 
collector, and the water is let back out to the sea again through low-head water 
turbines.
These devices are generally standing on the seabed. As the sea level varies the pres-
sure on the device varies. One part of the machine oscillates as the pressure varies, 
whilst another part of the machine is still and the relative motion between the two 
machine parts is utilised for electricity generation by means of e.g. direct drive (linear 
generator) or hydraulics.
Various other technologies have been proposed. None of these approaches to wave 
energy conversion has however advanced far in the development process to date.
Go to the EMEC website (http://www.emec.org.uk/wave_energy_devices.asp) to see 
animations of the different approaches to wave energy conversion
Example WECs
Pelamis, Dexa
Seabased Wavebob
WaveRoller, Oyster
Oceanlinx, Wavegen
Wave Dragon, WavePlane
AWS
CETO, Anaconda
Sweden
Seabased
Seabased is a Swedish WEC developer 
based in Uppsala. The company is an 
offspring from research at Uppsala 
University. 
Seabased is a two-body system; the reac-
tion force between the gravity founda-
tion and the buoyancy of the buoy drives 
the conversion to electric power, which is 
accomplished with a linear generator. 
Several Seabased machines connect to an 
underwater substation, where electricity 
is converted, transformed, and carried to 
shore. 
The technology has been tested since 
2006 off the Swedish west coast as a