Wave Power

The Pelamis is an offshore wave energy converter that uses the motion of waves to generate electricity. The machine
operates in water depths greater than 50m and is typically installed 2-10km from the coast. The machine is rated
at 750kW with a target capacity factor of 25-40 per cent, depending on the conditions at the chosen project site.
On average one machine will provide sufficient power to meet the annual electricity demand of approximately 500
homes. 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. Each of the power take-off units at the
joints of the machine are identical, and operate independently from each other with redundancy of all main components.
The power take-off system is driven by hydraulic cylinders at the joints, which resist the wave-induced motion
and pump fluid into high pressure accumulators, allowing generation to be smooth and continuous. The Pelamis
and its infrastructure are optimised for mass production for multiple-machine wave farms. As with every previous
generating technology, Pelamis Wave Power expects costs to significantly fall with continued deployment into the
market. Our onward development programme will focus on driving down the cost of energy produced by the Pelamis
machine in order to make the Pelamis fully competitive with offshore wind energy and other marine technologies.


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