Wave energy is a renewable and non-polluting source and its use is being studied in different countries. The paper presents an overview on the harnessing of energy from waves and the activities associated with setting up a plant for extracting energy from waves in Port of Pecem, on the coast of Ceara State, Brazil. The technology employed is based on storing water under pressure in a hyperbaric chamber, from which a controlled jet of water drives a standard turbine. The wave resource at the proposed location is presented in terms of statistics data obtained from previous monitoring. The device components are described and small scale model tested under regular waves representatives of the installation region. Based on the experimental results values of prescribed pressures are identified in order to optimize the power generation.

Small scale experiments and numerical simulations have been performed to evaluate a new concept of converter to produce electricity from wave energy. The models, tested in scale 1:10, have been submitted to different regular waves, with height and period representatives of the Brazilian coast, to evaluate the power generation and efficiency. The tests were carried out in a wave basin able to simulate in scale the wave conditions. Software especially written for the simulation of the converter behavior under regular waves has been initially correlated with the experimental results and, later on, it will be employed in parametric studies to estimate the best parameters of the system, in particular the prescribed pressure to be set for the best performance in terms of electricity production.

A device for electricity generation from ocean waves has been developed for installation on the Brazilian northeast coast. It is based on pumping modules and a two-stage accumulator linked to a hyperbaric chamber in order to provide a prescribed high pressure water flow, which operates a turbine coupled with an electrical generator. In the period between 2001 and 2007, wave tank testing of small-scale models have been carried out. A prototype with two pumping modules is presently installed in the Port of Pecém. This paper describes an overview of the device development since the first tests to the installation of the prototype. Wave climate analysis, design analysis and optimization studies have been developed and are briefly revised in this study. Furthermore, control strategies are proposed to optimize the electrical output considering the proper combination of both pressure and flow rate as a function of the predominant wave climate, when the applied pressure is constant and the generator is a synchronous machine.

No abstract

No abstract