The Sahara Desert is well known for being the world's largest hot desert, as it's probably a lot bigger than you even realize. It's nearly the same size as China. It spans across 10 different countries with three different time zones and is absolutely massacred by the Sun.
Over here is a map that shows annual sunshine hours across the world. In this, there are some notable hot spots like North America, South America, Australia, and Southern Africa. But no other place gets as much heat as the Sahara Desert. Most of this 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 receives. Most of this is because The Sahara Desert is pretty much directly along the Tropic of Cancer. This means the Sun for a lot of the year is pretty much directly over it. And the clouds pretty much never form or don't even exist over the entire desert. Which means all the sunlight received is never interrupted.
That's why the Sahara is the best location anywhere on earth to place solar panels and also to develop solar farms.
So, What if we covered the Sahara desert with solar panels?
According to World Energy Consumption & Stats, The total world energy usage in 2020 was 23.4 Terawatts Hours (TwH). Now, if we cover an area of the Sahara desert of around 2 million sq.km of area with solar panels which is roughly size of New Mexico, even with moderate efficiencies achievable easily today. it will provide more than 24 Terawatts hours (TwH) of power throughout the year. The Great Saharan Desert in Africa is 9.2 million square Kilometers and is prime for solar power (more than twelve hours per day). This means 20% of the Sahara desert would be sufficient to cover all of the electrical energy needs of the world in solar energy.
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. This means that its population density is on a par with Siberia. This further means it's possible to set up massive solar farms without too much of a negative impact on the local inhabitants.
But, What challenges will be there while covering the entire desert solar panels?
While there are many obvious benefits to constructing solar farms in the empty Sahara, there are also many 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 of 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.
As you can see in this map, there are only like few roads that even stretch across the Sahara. From north to the south, there are huge empty pockets of land across the desert without even a single road. This northwestern pocket of Chad is more than 600 kilometers away from the nearest road. So, 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 companies like Desert tech are only planning on constructing plants around the Sahara perimeter.
How much energy would we actually be able to produce after covering the entire desert solar panels?
In Sahara, a average 350 watts solar panel fully installed on a residential roof typically costs between 200 to 450$. But, it's going to be expensive to transport and install all of them in the middle of one of the world's most remote locations. Therefore, we're going to stick with high-cost estimates and add delivery of infrastructure fees as 300$ and 250$ more for installation. Conveniently, this math makes the total cost for each 350 watts panel exactly 1000$.
Considering that a typical solar panel generates roughly 350 watts of power. This earth-powering array would encompass around 70 billion solar panels. And it would roughly be the same size as the US state of New Mexico.
So if we take size of 400 sqkm of desert which requires 70 billion solar pannels which would roughly take to cover whole US state of New Mexico, but will be sufficient for our whole world electrical need. Now, We can figure out pretty quickly that the 70 billion solar panels would cost a whooping 70 Trillion Dollars. Now, that's approximately 80 percent of the world's GDP, resulting in immediately switch all of our electricity usages over to renewable solar. So that's pretty cool all right then.
Now, Sahara covers about 9 million Sqkm of area. That means the total energy available if every inch of the desert soaked up every drop of the Sun's energy – is more than 22,000 Terrawatt hours (TWh) a year. Which is 1000 times more enough to cover all over world electric needs. However, for generating this electricity would require around 315 billion solar pannels. Costing about 315 Trillon Dollars.
Now let's just assume that we've turned on infinite money. And we have expanded upon this by filling up the entire Sahara Desert with solar panels.
What will be the effects on surroundings after covering the entire desert solar panels?
Well, this overwhelming power given to humanity of harnessing the entire Sahara would also come with some costs. The black surfaces of the solar panels dotting the Sahara will absorb most of the sunlight hitting the Sahara. But 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 Sahara desert into a Green Sahara.
This will be good because it will open up a massive amount of land to colonization human settlement resulting in creating a chance of extensive economic 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. Now removing all of the sands of the Sahara desert could create a cascade of unforeseen events that would wipe out entire ecosystems in the Atlantic, the Amazon, and probably beyond. And could create an epic climate catastrophe. The likes of which 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. We only need 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 would have made some pretty decent progress here.
0 Comments