UC Berkeley

This thesis explores a novel concept in the area of

overtopping ocean wave energy devices. Current models of

overtopping devices are limited to locations which experience large

wave activity. The high energy associated with large waves enables

the ocean water waves to overtop the device ramp into the

collection reservoir which discharges through a power generating

turbine. The ramp height is necessarily large to establish a

sufficient collection reservoir head. The proposed design concept

can utilize small waves by implementing a gearing system which can

transfer water to the collection reservoir. This allows for greater

access to the wave energy resource at more locations than currently

possible.

After providing background to ocean wave energy devices the

wave resources of the California coast is investigated. The

formulation for wave energy is established and a statistical

analysis of eight locations from northern to southern California is

provided. Next important aspects for overtopping as well as

overtopping formulas are presented.

The modeling of an overtopping device with a gearing system

is presented and examined for a range of variables important to

overtopping. An analysis of the proposed design concept shows

promise for higher power output in the smaller wave environments of

southern California. Additionally for all locations considered the

gearing system concept improves power output over a conventional

overtopping device for some portion of the time. In addition,

survivability issues important for devices in the ocean environment

are treated using extreme value analysis and further areas of

research are suggested for future work.