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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