Papers presented to the 11th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 20-23 July 2015.
All actual Ocean Thermal Energy Conversion plants (OTEC)
that have been built or designed to date have been at sea level
or above. While the concept of OTEC is more than 100 years
old, the application has been very limited primarily because of
the cost of the plant and the power it produces in comparison
to other sources of power. Since OTEC plants are very
inefficient (around 3%), huge amounts of low-grade heat must
be supplied and rejected. Some authorities estimate that the
cost of piping cooling water from some 1000 meters below the
ocean surface represents nearly half of the plant cost. The
purpose of this paper is to explore the possibility of siting an
OTEC plant deep in the ocean and using it to drive a colocated
Sea Water Reverse Osmosis Plant (SWRO). A
thermodynamic analysis of this system is made to indicate the
potential improvement in performance.as compared to
conventional designs. Data on the performance and cost of
conventional plants are used in conjunction with the
thermodynamic analysis to give insight into potential
advantages of the proposed scheme for the case where it is
desired to produce desalinated water. Several advantages are
shown to result from employment of this system as compared
to conventional technologies including higher efficiency,
lower cost, resistance to environmental damage, and improved aesthetics. It is concluded that the potential improvements
from submerging an OTEC/SWRO plant, could lead to
significant penetration of the technology for this niche
situation.
