Waves vertical motion

This shore based system is built in Brazil

Electricity from waves is estimated to cost seven times as much as coal-fired power.


Wave harvester by Perpetuwave power.

Energy is transferred from the array of light weight hybrid floats and attached trailing arms to a common generator via a simple direct drive system.

Pelamis Wave Energy Converter

Float systems bend, squeezing the working fluid through onshore turbines.

The Pelamis machine is made up of five tube sections linked by universal joints which allow flexing in two directions. The machine floats semi-submerged on the surface of the water and inherently faces into the direction of the waves. As waves pass down the length of the machine and the sections bend in the water, the movement is converted into electricity via hydraulic power take-off systems housed inside each joint of the machine tubes, and power is transmitted to shore using standard subsea cables and equipment.

The Pelamis hides from big waves by diving through them, just like a surfer heading out to sea.  Website...

Pelamis is based in  Edinburgh Scotland

The first such farm to be used commercially was installed in Portugal.


At first, the farm was made up of only 3 Pelamis machines, but as the farm begins to have success, there are plans to up the number of machines so that as many as 1,500 households can be supported by the wave farm. Additionally, there are plans to construct a wave farm off the coast of Scotland.



Wave EnergyPower Take Off System.


Click image to play video


Click this image to play video.

The floats all turn the same axle to supply continuous power. The device is anchored with a single anchor line. 

The angle is varied according to wave conditions. Wide angle for smaller waves.  Click on image to play video.


A float travels up and down with the waves and operates a pump to pressurise sea water which is piped ashore. Many individual pumps are connected together to produce an even pressure.

Once ashore the pressurised water can be used to drive a turbine or desalinate water.


Ocean Power Technologies

The buoy rides up and down with a rod moving through the centre of the buoy. "The resultant mechanical stroking is converted via a sophisticated power take-off to drive an electrical generator." (They think we are idiots.)



Fortum is a large enrgy company planning to build a large wave farm in Sweden


McCabe Wave pump


Euro Wa​ve Energy



Bolt lifesaver wave power

The buoy is moored to the bottom with 3 taught cables. The motion tightens and loosens the cables (presumably against a spring) that then turn a generator.



Brandl generator

 (1) Magnets (2) coils (3) Float (4) spring (5) pendulum mass

"A floating round disk of about 10m in diameter and 1 m thickness and a hollow cylinder perpendicular to the coils of the linear generator and fall with the waves. In the hollow cylinder opposite swinging a pendulum mass together with the magnets which induce by their relative movement to the coils an electrical current."

StingRAY  Website

Resen - Denmark

The buoy is tethered to the bottom with a taught line. On the buoy it is attached to one end of a lever (yellow). The motion pulls the lever up and down turning a set of gears and a generator.

In large waves the buoy is pulled under the crest, thus avoiding damage.

Website    Test results

GMR bu​oy - Galicia Mar Renovables

Play video

The tower is fixed to teh bottom and the float rides up and down. Energy is removed via a rack and pinion gear.

Penguin Wave Energy Converter

The Penguin is designed by Wello Oy in Finland to capture rotational energy generated by the movement of its asymmetrically shaped hull, which rolls, heaves and pitches with each passing wave. This motion is used to spin an asymmetric flywheel. This drives an electric generator to produce electricity.


Wello Oy  Penguin

Perhaps the flywheel could be connected directly to a propeller shaft for propulsion?


Click on image to play video


Norway  and Europe  Website

WET-NZ is being tested as the first customer at the new Oregan wave farm  Website

Blue Energy - Ocean Power

A series of patented ideas  using floats to drive a pump for either air or water.   Source


Idea from Israel


IWave - Indian Wave Energy Device

It is a floating device tethered with chains to piles driven to ocean bottom. The wave action raises the heavy partially buoyant piston that drives the overhead crankshaft by half turn. The receding wave drops the piston completing the balance half turn. One revolution is obtained for every wave. Using gear box and generator the current is produced continuously. Website

Play video


Other groups working on this approach




Electricity generating wave pipe EGWP

The patent diagram looks like a float inside a pipe. The patent has lapsed in Aust.  Website