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More energy will fall on the world’s deserts in 6 hours
than the entire world will consume over the next year.
The Sahara desert is well known for being the world’s largest hot desert,
but it’s probably a lot bigger than you even realize.
It’s nearly the same size as China,
it spans across 10 different countries and 3 different time zones,
and it gets absolutely massacred by sunlight.
This is a map that shows annual sunshine hours across the world.
There are some notable hot spots in North America, South America, and Southern Africa,
but nowhere gets as much as the Sahara Desert.
Most of this China-sized chunk of land gets more than 3600 hours of sunlight a year,
and within that big chunk is this other chunk that gets more than 4000 hours a year.
For reference, that’s nearly four times the amount of annual sunlight that Germany gets.
Most of this is because the Sahara Desert is
A, pretty much directly along the tropic of cancer
which means the sun for a lot of the year is pretty much directly over it,
and B, clouds pretty much never form or even exist over the entire desert.
which means all that sunlight is never interrupted.
The Sahara consequently is the best location anywhere on earth
to place solor panels and develop solar farms.
So then begs the question, what if we cover the entire desert with solar panels?
How much energy would we actually be able to produce and how would this change our planet?
Let’s take a deep dive.
For starters, let’s begin here.
This is the where’s that solar power station in Morocco,
the world’s largest concentrated solar power plant currently in existence in a marvel of modern engineering.
Once fully completed and operational,
the plant will take up an area of 25 square kilometers
and be capable of producing 582 megawatts of electricity.
It will even be capable of storing solar energy in the form of superheated molten salt,
which allows for further production of electricity even into the night.
After investing more than 9 billion dollars into their solar energy objective,
Morocco aims to create 4 additional plants similar to this one in the Sahara
that will collectively create more than 2000 megawatts of electricity production
which will be enough to provide for roughly 38% of all of Morocco’s annual electricity needs.
This project will transform Morocco into the world’s leading solar energy state,
and as the only African country that currently has a power cable linked to Europe,
much of this energy will be exported for profit to the countries of the European Union.
But all of this energy is created from just five relatively small plants.
What happens when we scale things up a bit and think bigger?
One of the few organizations thinking about Sahara solar energy production in the future
is the German Energy Company Desertec
which happens to be an investor of the Moroccan Solor Energy Project.
Acorroding to their research and data taken from the German Aerospace Center,
a solar panel array of just this small size in the Sahara
could power 100% of Germany’s entire electricity needs,
an array of this size could power the entire Europeen Union,
while an array of just this size could power the entire world’s modern electricity needs
at approximately 18 trillion watts give or take a bit.
Considering that a typical solar panel generate roughly 350 watts of power,
this earth-powering array would encompass around 51.4 billion solar panels,
and will be roughly the same size as the US state of New Mexico,
quite a large amount of land but it’s nothing when compared with the vastness of the Sahara
that also happens to be incredibly sparsely populated.
Only about two and a half million people live across the Sahara,
which means that its population density is on a par with Siberia,
which further means that it’s posible to set up huge solar farms like this
without too much of a negative impact on the local inhabitants.
The desertec project doesn’t quite intend on transforming the entire Sahara into a solar farm,
but it’s still quite ambitious.
The general idea is to set up a series of massive solar farms
across the Sahara’s perimeter and deeper into the Middle East.
Once constructed, this connection of solar farms will provide
for the majority of Africa’s and the Middle East’s electricity needs,
while shipping any excess power across cables to Europe,
that could supply as much as 15% of the continent’s entire electricity needs.
This is a real-life plan that’s undergone significant amounts of research and investment.
But why are they only planning on building solar farms around the Sahara’s perimeter?
Well, while there’s lots of obvious benefits to constructing solar farms in the empty Sahara,
there’s also lots of problems.
First of all the Sahara‘s emptiness itself is both a blessing and a curse
On the one hand, it means that almost nobody will have to be relocated or moved off their land,
but on the other hand there isn’t any infrastructure to actually get
the massive amounts of supplies into place in any kind of cost effective manner.
I mean look at this map.
There’s only like four roads that even stretch across the Sahara from the north to the south.
There are huge empty pockets of land across the desert without a single road at all.
And some of these areas like this northwestern pocket of chad
are more than 600 kilometers away from the nearest road.
Transporting billions of solar panels to a remote area like this
will necessitate building countless new expensive highways or railroads to get them there,
and that’s why Desertech is only planning on constructing plants around the Sahara.
But let’s forget all of that for a moment and just think about
the cost of the solar panels themselves in a Sahara sized array.
A pretty average 350 watt solar panel typically costs
anywhere between 200$ and 415$ once fully installed on a residential roof today.
Since we know that it’s going to be expensive transporting and installing
all of them in the middle of one of the world’s most remote locations,
we’re going to stick with a high cost estimate here
and tack on an additional 300$ delivery infrastructure fees
and 250 more dollars for installation fees.
Conveniently, this math makes the total cost for each 350 watt panel exactly 1000$,
so from there you can figure out pretty quickly that the 51.4 billion solar panels
needed to fit inside of our New Mexico sized array
that’ll power the entire planet will cost a cool 51.4 trillion US dollars.
For reference that’s approximately 60% of the entire world‘s GDP
but it would enable us to immediately switch all of our electricity over
to renewable solar, so that’s pretty cool.
All right then, now let’s just assume that we’ve turned on infinite money
好了 现在我们就假设一下 钱不是任何问题
and we expended upon this by filling up the entire Sahara desert with solar panels,
what is going to happen now?
Well, for starters, if we assume that the solar panels are 100% efficient,
the entire Sahara desert will probably now be producing somewhere around the neighborhood
of 1.3 million terawatt hours of electricity per year,
so to put that number into perspective, the entire contemporary human species
consumed about 173,000 terawatt hours of energy in 2019,
and that’s not just electricity, that’s all energy consumed for everything we did that year.
A Sahara desert covered in solar panels would generate more than seven times the amount of energy
that all of the nearly 8 billion humans of the world collectively consume right now.
Obviously this would present revolutionary changes to what mankind could be capable of
and not just even closer to a type 1 Kardashev style civilization,
but this overwhelming power given to humanity by harnessing the entire Sahara
would also come with some significant costs.
The black surfaces of the solar panels dotting the Sahara
will of course absorb most of the sunlight hitting the Sahara.
Only a tiny fraction of that incoming energy will actually be converted into electricity,
while the overwhelming majority will be returned back to the environment as heat.
In turn this heat will trigger a sort of feedback loop
in which the heat emitted by the solar panels would create a steep temperature differential
between the land and the surrounding oceans.
This will ultimately lower the surface air pressure and cause moist air to rise
and condense into clouds and rain across the desert.
So by covering the entire Sahara with solar panels
will also unwittingly be terraforming the desert Sahara into a green Sahara at the same time.
In some ways this will be good,
because it will open up a massive amount of land the size of China to colonization, human settlement
and critically for the emerging economies of North Africa
extensive economy development for their countries and their people.
But in other ways this will be really bad.
The Amazon rainforest over in South America is extensively fed and fertilized by dust
coming over from the Sahara that gets blown across the Atlantic,
while the Atlantic ecosystems themselves also benefit from this fertile dust as well.
Removing all of the sands of the Sahara desert could create a cascade of unforeseen events
that could wipe out entire ecosystems in the Atlantic, the Amazon and probably beyond,
这些后果可能会彻底摧毁大西洋 亚马逊 甚至可能更外围的整个生态系统
and create an epic climate catastrophe the likes we have never seen before.
In summary, covering the entire Sahara with solar panels would be epic,
but it’s also not feasible, it’s probably pretty dangerous and it’s not even necessary either.
但这也是不可行的 而且可能十分危险 甚至没有什么必要这样做
We only needs solar panels covering the area of New Mexico
to meet all 8 billion humans modern electricity needs,
and they don’t even need to be all in the same place.
They can be spread out across all of the world’s deserts or anywhere where it’s sunny.
And hopefully by the end of the century we’ll have made some pretty decent progress here.
Now maybe you are sitting here wondering how solar panels and solar energy actually work.
In order to help myself better understand that very thing for this video,
I took the full solar energy course that’s offered on Brilliant.
Maybe you’re interested in the very same thing,
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好吧 你已经在YouTube上观看教育类视频了 这是个不错的开始
but in order to really learn something, you’ve got to actually do it,
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你可以直接跳到解决问题的环节 一步步接收辅导 然后在你意识到之前
you‘ve learned a new subject in STEM.
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Brilliant上的每个课程都跟这个课程一样 互动性强 容易理解
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But now, Brilliant has helped me so much with learning about all of these things
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And they help me make videos like the one you just watched.
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And as always, thank you so much for watching.
This video is made possible by brilliant.