(published in The New Citizen, February 2002, reprinted in April 2006 edition.)
Nuclear desalination, researched
since the 1960s, is
a technology ready for take-off as
a clean, economical source for
supplying safe drinking water
from seawater. As Lance Endersbee
makes clear, there is no time
to waste in planning and building
desalination plants that can
meet the looming deficits of fresh
water for the world’s population.
Conventional desalination
plants powered by the steam or
electricity that is produced by gas
or oil, have been operating for 50
years, and in 2001, there were
12,451 desalination plants worldwide.
In the Gulf region and North
Africa, desalination supplies
about one million cubic meters
per day of water, while Saudi Arabia,
which is even more dependent
on desalination, has a capacity
of four million cubic meters per
day. The Mideast and Gulf regions
are the largest users, with
more than 50% of the world’s desalination
capacity.
Nuclear desalination complexes (nuplexes) such as
this could produce “rivers of water”, and transform Australia and the other dry
areas of the world.
There are three main desalination
technologies: reverse osmosis,
or RO, which is used in nearly
half of today’s desalination
plants; multi-effect distillation
(MED); and multi-stage flash distillation
(MSF). All three technologies
are still undergoing research
to improve efficiency and
cost.
Nuclear Desalination Most
Attractive
Any power plant—even a small
diesel engine—can be coupled to
a desalination facility. But nuclear
plants are the most attractive
power source for desalination, because
they are more energy-intensive
than plants fired by conventional
fuels, and cleaner. Although
almost any kind of nuclear plant
could be used to power a desalination
facility, the fourth-generation
high-temperature nuclear reactors
which are 50% more efficient,
modular, mass-producible,
and super-safe-are ideal for the job.
Because of its passive safety characteristics
and smaller design, the
new high temperature reactors (either
the South African Pebble Bed
or the prismatic core model of General
Atomics), can be easily sited
near the water-distribution systems.
Especially for developing-sector
countries, which do not have large
power grids, the small to medium-size,
fourth-generation reactors are
economical, because they can be
added to the grid module by module,
as demand increases.
For industrialised countries,
larger nuclear plants are appropriate.
In fact, in the 1980s, the Metropolitan
Water District of Southern
California, which serves the
large desert population of more
than 15 million people, proposed
building a large desalination facility
powered by a high-temperature
gas-cooled reactor of the General
Atomics design. The desalination
process was designed to directly
use exhaust heat from the
reactor. Although economically
and technologically feasible, the
project was killed by the environmental
Malthusians.
The International Atomic Energy
Agency has conducted research
and feasibility studies on nuclear
desalination since the Atoms for
Peace days. In its recent studies,
the IAEA has stressed that nuclear
desalination is cost competitive
against other energy sources; it has
inherent advantages, such as no
pollution, continuous operation,
and a secured fuel supply; and that
both the heat and/or the electricity
produced by a nuclear reactor
can be used for desalination, permitting
flexible design concepts.
—Marjorie Mazel Hecht