our planet's surface is
covered in water. Three
hundred and thirty two
point five million cubic
miles of it.
Three hundred and sixty
six billion billion
gallons. That's over forty
eight billion gallons
of water for every
person on Earth.
But today, one out of
three people don't have
access to safe
drinking water.
Some projections will show
by 2050, more than
half our population will
be living in
water-stressed areas. That's
over four billion
people. These aren't just
issues in developing
countries. Something you
hear about elsewhere.
These are things that
are happening in our
communities all the time.
Worried and angry about
lead contamination. The military
in remote parts
of Puerto Rico. And that's
the result of many
things. But one of them
is that ninety six point
five percent of that water
is found in our
oceans. It's saturated with
salt and undrinkable.
And most of the earth's
freshwater is locked away
in glaciers or
deep underground.
Less than 1 percent of
it is available to us.
When you dig a little
bit and look under the
surface, even here in the
United States, we have
large numbers of people that
don't have access to
safe, clean
drinking water.
So why can't we just
take all that seawater,
filter out the salt and
have a nearly unlimited
supply of clean,
drinkable water?
Desalination broadly is the
process of removing
salts from water.
It's been practice
for years.
In fact, it's
a natural process.
It occurs when the sun
heats the ocean and fresh
water evaporates off and
it falls again as
rainfall. If you mix
salt into water, it
dissolves. And if you
could watch microscopically
while you did that, you'd
see that the water is
actually breaking apart the
salt into charged
particles that chemically
interact with the
water. So salt water
is a chemically new
solution. It's not just
water with some salt
grains floating around
in it.
And that's why desalination
is a fundamentally
tricky process. The two
main types of
desalination are thermal
desalination and reverse
osmosis. Thermal desalination is
the oldest form
of desalination.
It's essentially boiling water
and then capturing
the steam and turning
that into freshwater.
But in the 60s, we
were able to develop reverse
osmosis processes at UCLA
and these have now
started to dominate
the market.
So one of the chief
differences between the two
is reverse osmosis doesn't
use heat, doesn't boil
anything. You're really
just pressurizing the
water to a tremendous
amount and you're forcing
it through a membrane where
it doesn't want to
go. It wants to
stay with the salt.
But with this high pressure,
it is forced to
separate from the salt.
Broadly speaking, what you want
to look at for
desalination is where's my
freshwater coming from
and do I have enough of
it? And if I don't have
enough of it, do I
need to augment supply?
Desalination then starts to
become a very
attractive or
interesting option.
Which is why the
vast majority of desalination
efforts right now are
happening in places like
the Middle East
and North Africa.
Rich with fossil fuels,
but also experiencing
extreme water scarcity.
Just two countries, Saudi
Arabia and UAE, they
produce one fourth of
the desalination water that
is produced currently
on this planet.
Concerns about desalination
fall broadly into
three categories: the amount
of energy required,
how much it costs,
and its environmental impacts.
There are some that really
see it as a key
solution. There are others
that push back and
argue that it's
very energy intensive.
It's very expensive.
It has impacts on the
marine environment and that
we should pursue
alternatives first.
It requires a tremendous
amount of energy to
basically break up that
bond between the water
and salt. Ocean water desal
can be twenty five
times as energy intensive
as other freshwater
approaches. Historically, the
impediment for sea
water desalination being more
abundant or popular
in North America
has been cost.
It has been
cost prohibitive historically.
The Cloud Lewis
Carlsbad desalination plant
outside of San Diego is
the largest of its kind
in the Western Hemisphere
and has been operating
since 2015, producing 50
million gallons of clean
water a day. It's in
San Diego County because of
its dry, arid climate.
The county has historically
imported nearly all
of its water from the
Colorado River and Northern
California. In San Diego,
in Carlsbad example,
they are spending twice
as much for seawater
desalination as they do
on imported water.
Now, they were looking at
it and saying, well, at
some point in the future,
the costs will be
comparable. And I think some
folks point it to
the fact that, well, when
that's the case, then
that's probably when you
should build it.
Today, desalinated water
in Carlsbad costs
approximately twice as much
as imported water.
You're comparing apples and
oranges because that
imported water is coming
from systems that were
built half a century ago
where all the capital
investment has been
paid off.
Standing down for 5 or
10 years, hoping there's
some major breakthrough in
the technology is not
going to materially reduce
the cost of building
infrastructure. That's not unique
to desal and
water. It's true of
all public infrastructure.
We have a huge deficit.
We need to start building
not just water, but
transportation and
housing.
Now, not 5 or
10 years from now.
The Carlsbad Plant is
operated as a
public/private partnership with
the Carlsbad
Seawater desalination
plant.
In the proposed
Huntington beach seawater
desalination plant, we're
proposing a
public/private partnership where the
plant is 100
percent privately financed and
then we enter into
a longterm, fixed-price
water purchase agreement
with the public
water agency.
Essentially, we're recovering
our investment over
time through the
sale of water.
There's an infrastructure deficit
in the United
States. There's certainly
an infrastructure
deficit in California.
And you can't expect
local, state and federal
government to pay for
all of it.
The private sector is going
to have to invest
private dollars. And I
think there's a huge
opportunity in water in a
way that both protects
the ratepayers and also
allows for the investment
of private capital beyond
the environmental costs
of producing the energy
needed to power these
plants. Another concern
arises because they're
not just outputting
clean desalinated water.
They're also producing huge
amounts of hyper
salty water, called brine,
as a byproduct.
Seawater desalination plants
that use reverse
osmosis typically operate at
a 50 percent
efficiency in that if you
take in two gallons of
seawater, you're going to
produce one gallon of
fresh water and one gallon
of hyper saline brine.
It's a fixed volume of
salt that I'm trying to
remove. So whether I put it
in half a gallon of
water or a tenth of a
gallon of water, it's still
going to be there and
it's going gonna be much
more concentrated. As
desalination efforts grow,
it's not clear what should
be done with these
huge amounts of brine.
Globally right now, we're
producing over 37
billion gallons a day.
Most brine is in one
way or another emptied back
into the ocean. But because
it has a much higher
salt concentration than regular
seawater, it has
the potential to, among other
things, sink to the
sea floor and wreck havoc
on the plants and
animals found there. In
addition, because these
facilities are taking in
millions of gallons of
seawater a day, the
intake itself could destroy
local marine life. But
Poseidon Water, which
operates the Carlsbad plant,
says the regulations
in California provide
sufficient environmental
protection. Numerous studies have
been done in
California and around the
world that show that
level of salinity increase
will not harm marine
life. And you're also
providing drinking water to
people in need. But a
recent study published in
2018 showed that we're
producing even more brine
than we thought. For
every liter of desalinated
water, we produce 1.5
liters of brine.
In other words, overall,
we are producing more
brine than we
produce desalinated water.
And while some places
like California have robust
regulations regarding brine in
place, it's not
clear that as a whole
the industry is taking its
disposal seriously
enough.
Currently, we are disposing of
brine in a way
which we use to dispose
of industrial waste water
about 40-50 years ago.
So if desalination uses a
huge amount of energy,
is very expensive compared
to other options, and
in the end we're
producing more potentially
harmful brine than clean
water, why do we
continue to pursue it?
Desalination has its drawbacks,
but one of the
benefits is that it's a
fairly stable and known
process particular for dealing
with ocean water.
You can be confident that
it will supply you
water when you need it.
Reliability is the key.
Water scarcity is a
complex, difficult problem.
Climate change is
affecting everything and
introducing growing
uncertainty.
Weather is variable, but
if you have a
desalination plant, energy, and
sea water, you
can reliably get
clean water.
But desalination undeniably uses
a large amount
of energy. And for
some, it's just fundamentally
difficult to advocate for
a technology that would
be adding to our
ever growing energy needs.
I think when we start
to look into these
water-scarce worlds, we start
to think about well
energy provides
us services.
It heats our homes, it
lights our offices and
buildings. And if we think
of energy as a service
that could give us water
for some context, you
know, the average person
in the U.S.
uses about a hundred gallons
of water per day.
If I were to produce
that hundred gallons per day
with ocean water desal, that
would be the same
electricity consumption that
my home would
require over an hour. So to
kind of put things in
context, I think we start
to think about our
energy resources and where
do I invest it?
How important is water?
It is the most
basic element of life.
And people go out and
they buy a venti Starbucks
every day and spend more on
that than they do for
a month's supply
of desalinated water.
And they don't realize
it. It's clear that
desalination alone is not
going to fix the
world's water problems.
Up in some places where
you're just water rich,
desalination probably won't make
the most sense.
Poseidon Water as a company
does not believe that
seawater desalination is
a panacea.
We can't just build one or
two or 10 and really
solve our
water challenges.
Desalination is not the
solution to water
scarcity. It's one of the
options to narrow the
gap between water
supply and demand.
But for some communities
around the world, it's
already making an
enormous local impact.
It's currently a pretty
small fraction of the
water supply globally and
probably will remain
so. There are, though,
communities for which it
is a fairly
significant contribution.
It can be quite important
at the local level.
Desalination is one
tool of many.
And for it to have
maximum impact, it must be
implemented alongside
other techniques.
Israel maybe provides a
good example where they
have invested quite a
bit in seawater
desalination, but they also
made investments in
efficiency such that their water
use on a per
person basis is far lower
than we see here in
California or in many, many
parts of the United
States. So they did those
things first, so that
they aren't wasting that
very expensive water.
That then delayed their need
to build a plant.
And when they built it, they
could build it a bit
smaller than they
would have.
So there's a cost, a
real cost savings there to
the community. I would almost
look at it as a
safe bet, you know,
to hedge your risks.
A desalination plant is your
low risk option in
your portfolio. Kind of
expensive, maybe, but
it's going to deliver. I
think we do the cheaper,
less environmentally damaging
things first.
That seawater desalination
is an option.
In some communities, they
don't have other
options. Others, though, do
have other options.
They can use water
more efficiently, which can
save water, save energy,
can have less
environmental impact.
And while most attention
is given to seawater
desalination, a similar process
can be used for
treating many other sources
of water like
wastewater. The volume of
waste water, if it's
all collected and recycled,
that is almost
equivalent to five times the
volume of water that
passes through Niagara
Falls each year.
And if we look at
the desalinated the water, the
desalinated water, which we
produce globally, on
an annual basis is almost
equal to half of the
volume of the water
that passes through Niagara
Falls. We don't want to
lose sight of other sorts
of desal, brackish water, which
is, you can think
of brackish water is it's
not as salty as ocean
water, but it's
saltier than freshwater.
It's that whole space
between and there the
energy requirements are
substantially less simply
because there's less salt.
So less salt, less
stuff to remove,
less energy.
Desalination is an important
tool in the fight
against water scarcity.
Its reliability is becoming
ever more important,
but it's not a
cure-all and other techniques
should always be
implemented alongside it.
Desalination is already
vital for many
water-scarce communities around
the world.
And as climate change
continues to transform our
planet, the balance between
concerns about energy
use and the ability to
reliably get clean water
is going to evolve.
How exactly desalination will
fit into the future of clean
water is yet to be
seen.
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