  Ocean waves provide a consistent, reliable source of clean energy making them
a viable energy source for desalination. Ocean wave energy is useful to coastal
communities, especially island nations. However, large capital costs render
current wave-powered desalination technologies economically infeasible. This
work presents a high efficiency configuration for ocean wave energy powering
batch reverse osmosis. The proposed system uses seawater as the working fluid
in a hydro-mechanical wave energy converter and replaces the reverse osmosis
high-pressure pump with a hydraulic converter for direct-drive coupling. This
allows for minimal intermediary power conversions, fewer components, and higher
efficiencies. The concept was analyzed with MATLAB to model the transient
energy dynamics of the wave energy converter, power take-off system, and
desalination load. The fully hydro-mechanical coupling, incorporating energy
recovery, could achieve an SEC and LCOW as low as 2.30 kWh/m3 and $1.96,
respectively, for different sea states. The results were validated at the
sub-system level against existing literature on wave energy models and previous
work completed on batch reverse osmosis models, as this system was the first to
combine these two technologies. SEC and LCOW values were validated by comparing
to known and predicted values for various types of RO systems.
