An oscillating water column type wave energy power plant has been set up off the south-west coast of India near Trivandrum. The system consists of a caisson 23.2 m × 17 m in plan, 18.3 m high in reinforced concrete, resting on a prepared sea bed in 10.2 m water depth. The caisson was built and placed in position in December 1.990 and the power module erected in October 1991 and trial runs on power generation started in November 1991. The paper explains the concept of the caisson and describes its analysis, design, construction and installation aspects. The caissons can simultaneously be used as a breakwater for a harbour.
Wave energy is one of the promising forms of renewable source of energy which has received considerable attention. Sponsored by the Department of Ocean Development, Government of India, al pilot plant to generate electricity from Ocean waves has been built off Trivandrum coast by the Ocean Engineering Centre, IIT, Madras. The system consists of (a) Concrete Caisson (b) Power module mounted on the top, comprising of a butterfly valve, an air turbine and an induction generator. Fig. l(a) shows the cross section of the system, 1 (b) the plan of caisson, 1(c) the location plan and 1(d) the cross section showing the system and the approach bridge connecting to the breakwater.
The Oscillating Water Column (OWC) concept, chosen for absorption of energy from waves, consists of a chamber exposed to wave action through an entrance in the front. Under the wave action, air inside the chamber gets compressed and rarified. The bi - directional air movement is used to drive a special type air turbine known as Wells turbine (Fig. 1(a)).
