SCIENTISTS UNEARTH A CONSEQUENCE OF SOLAR PANELS IN THE SAHARA

[Dashinka 24,786]

Unintended consequences.

 

SCIENTISTS UNEARTH A CONSEQUENCE OF SOLAR PANELS IN THE SAHARA

 

A GREENER SAHARA

A 2018 study used a climate model to simulate the effects of lower albedo on the land surface of deserts caused by installing massive solar farms. Albedo is a measure of how well surfaces reflect sunlight. Sand, for example, is much more reflective than a solar panel and so has a higher albedo.

The model revealed that when the size of the solar farm reaches 20% of the total area of the Sahara, it triggers a feedback loop. The heat emitted by the darker solar panels (compared to the highly reflective desert soil) creates a steep temperature difference between the land and the surrounding oceans that ultimately lowers surface air pressure and causes moist air to rise and condense into raindrops. With more monsoon rainfall, plants grow and the desert reflects less of the sun’s energy since vegetation absorbs light better than sand and soil. With more plants present, more water is evaporated, creating a more humid environment that causes vegetation to spread.

This scenario might seem fanciful, but studies suggest that a similar feedback loop kept much of the Sahara green during the African Humid Period, which only ended 5,000 years ago.

So, a giant solar farm could generate ample energy to meet global demand and simultaneously turn one of the most hostile environments on Earth into a habitable oasis. Sounds perfect, right?

Not quite. In a recent study, we used an advanced Earth system model to closely examine how Saharan solar farms interact with the climate. Our model takes into account the complex feedbacks between the interacting spheres of the world’s climate – the atmosphere, the ocean, and the land and its ecosystems. It showed there could be unintended effects in remote parts of the land and ocean that offset any regional benefits over the Sahara itself.

 

https://www.inverse.com/science/why-turning-the-sahara-into-a-giant-solar-farm-could-damage-the-global-climate

 

https://science.sciencemag.org/content/361/6406/1019

[millefleur 5,047]

Every single energy source has downsides and produces adverse affects. There is no 100% "clean" energy without some form of environmental impact. It all comes down to weighing up the pros and the cons of cost to adverse affects. I think solar panels make sense on a small scale but on a mass scale, I'd be concerned. Plus the desert isn't exactly a complete waste land, there are animals well adapted to live there and even people, such as the Bedouins.

 

Also, the dust of the Sahara is what gives us wonderful sunsets across the Atlantic, and we don't want to lose that!

[Dashinka 24,786]

7 minutes ago, millefleur said:

Every single energy source has downsides and produces adverse affects. There is no 100% "clean" energy without some form of environmental impact. It all comes down to weighing up the pros and the cons of cost to adverse affects. I think solar panels make sense on a small scale but on a mass scale, I'd be concerned. Plus the desert isn't exactly a complete waste land, there are animals well adapted to live there and even people, such as the Bedouins.

 

Also, the dust of the Sahara is what gives us wonderful sunsets across the Atlantic, and we don't want to lose that!

You are absolutely correct.  A good system will have a mix of sources for reliability as well as to reduce the carbon footprint.  The folks that seem to be pushing a move toward 100% wind or solar (hydro is often not a preferred renewable) often ignore the environmental costs and carbon footprint associated with these technologies.  Anytime we fabricate something using the natural resources of the planet, we create pollution in some form.  Of course we should try to minimize or mitigate this environmental damage, but that also can have a carbon footprint.