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OWEC - Offshore Wave Energy Converters

The IPS OWEC Buoy  is based on almost twenty years of theoretical studies, laboratory test, model tests in lakes and full scale trials in the open sea.

The system is very flexible and will produce electrical power with high efficiency - a total yield of 30 - 35% from waves to electricity is normal under good conditions.

The basic unit in the IPS-OWEC system is a circular or oval buoy with diameter and weight adopted to the predominant wave situation at the place of location.

The buoy is held in position by an elastic mooring enabling it to move freely up and down against a damping water mass contained in the long vertical tube - the acceleration tube - underneath the buoy. The relative movement between the buoy itself and the water mass is transferred by a working piston in the acceleration tube into an energy conversion system located within the buoy hull.

Production buoys with diameters from 3 - 4 m up to 10 - 12 m can be arranged in groups from 5 units and upwards. Every unit can be a complete power station. Alternatively groups of IPS OWEC Buoy may be connected to a central generation unit.

For best performance a water depth of minimum 30 m is required. The design can be modified to operate also in shallower waters but with reduced efficiency.

The IPS system also has built-in overload protection arrangements, control programs and instruments to adept the function of every buoy unit to changes in the wave height, wave spectrum etc.

The simulation programs developed by IPS give a very accurate picture of the OWEC’s behavior in various situations. For proper estimation and design it is important, however, to have detailed long-term wave data from the proposed location.

The internal energy conversion system within the IPS OWEC Buoy can be of different types. Traditionally an oil hydraulic system has been used. This has been built up of well known standard components - cylinders, accumulators, valve blocks, hydraulic motors etc. which guarantee good serviceability and long life.

A new interesting alternative for the internal energy conversion is based on a set of hose pumps driven by the piston in the acceleration tube, pumping water to a small turbine directly coupled to a special generator.

The IPS system design alternatives are protected by a series of international patens.

The latest patents where filed in 1996 and have been granted in a number of countries - applications in other countries are still pending

In the waters west of Scotland and Ireland where the power "content" in the waves is in the order of 50 - 70 kW/m wave front, a 10 m IPS OWEC Buoy will reach a power of 150 - 250 kW and produce more than 1.4 GWh of electric energy per year.



     This page was updated on :03/23/2009