B1 Intermediate US 10 Folder Collection
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Seventy one percent of 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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Can Sea Water Desalination Save The World?

10 Folder Collection
day published on June 9, 2020
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