What if we turned the Sahara desert into a solar 'battery'?

Theoretically, we could meet the world's current energy needs by covering 1.2% of the Sahara Desert with solar panels.

Finding green energy

In recent years, as the consequences of climate change have become increasingly apparent, our interest in green energy sources has increased. An energy source that does not use fossil fuels and has a negligible carbon footprint is essential for our long-term survival.

The desert has an abundant supply of sunlight.

Nuclear energy can be one of the effective solutions, as it does not emit carbon. However, not all countries in the world can produce or buy nuclear power plants, as they require a lot of resources and have a high risk of nuclear accidents.

What about wind turbines? They are a clean and sustainable source of energy, but they are noisy and can pose a risk to local livelihoods. The wind does not always blow, so the energy output is inconsistent.

Solar power plants face the same problem. The sun does not always shine brightly in the sky and there are areas where sunlight is weak or the sky is mostly cloudy. However, in the desert things are different.

The desert has an abundant supply of sunlight , making it an ideal place to build solar power plants. So why don't we cover part of the Sahara Desert with solar panels?

The Sahara has long been seen as a potential energy battery for Europe.

The key lies in the Sahara

According to German physicist Gehrard Knies, in just six hours, deserts around the world receive a lot of solar energy (173,000 terawatts, more than humans consume in a year).

The Sahara Desert in Africa covers an area of ​​9.2 million square kilometers, if 1.2% of the Sahara Desert area - about 110,000 square kilometers - were covered with solar panels, it would be enough to meet the energy needs of the entire world.

Additionally, deserts have extremely low rainfall, little to no cloud cover, limited wildlife, and a negligible human population. These attributes make the desert practically useless for any human benefit. But at the moment, it could be the world's treasure and our best bet for producing clean, sustainable solar energy. So who will do it?

The Sahara Desert in Africa covers an area of ​​9.2 million square kilometers.

Solar projects in the Sahara have been talked about for years, but the Sahara's solar potential has yet to be realized, with only the Noor project in Morocco currently operating in the region.

There are a number of reasons for this, including political instability in the MENA region which has discouraged potential investors from taking the risk. Furthermore, transmission costs, solar panel costs and plant maintenance have discouraged investors in the past.

The Sahara has long been seen as a potential energy battery for Europe. In 2013, the €400 billion Desertec project collapsed due to problems related to feasibility, transportation and cost.

If successful, the energy generated would be transported via submarine cables to Italy, Malta and France.

In recent years, TuNur , a small UK-based company, has applied to the Tunisian government to begin construction of a 4.5GW concentrated solar power (CSP) project in the Sahara Desert. If successful, the energy generated would be transported via submarine cables to Italy, Malta and France, providing Europe with a new, carbon-free alternative energy source.

' The TuNur project is a fully integrated solar export project, so it combines solar generation in Tunisia with dedicated transmission links to the European electricity grid,' explains Daniel Rich, CEO of TuNur.

The project will be located near Réjim Maâtoug in the Kébili Governorate in southwestern Tunisia, where TuNur has agreed to lease land from a local tribe. In the summer, temperatures here reach 34 degrees Celsius with 12 hours of sunshine a day.

When fully built, the project will be three times the size of Manhattan. Hundreds of thousands of parabolic mirrors will be arranged to direct the blazing Saharan sun onto CSP towers that will be up to 200m high.

Heat would be stored in the molten salt that runs through these towers, heating steam to turn turbines, and the salt can retain heat for hours so electricity could be continuously generated long after the Sun stops shining.

 Photovoltaic panels covering the Sahara desert could be the solution to our electricity needs.

If deployed, the Saharan solar system could provide electricity to two million European homes. If the TuNur application is successful and the project becomes a reality, it could mark a major step forward for Saharan solar, CSP technology, and could provide electricity to two million European homes.

What if humans get greedier and want to turn more desert areas into solar power production sites?

Large-scale photovoltaic (PV) panels covering the Sahara Desert could be the solution to our electricity needs, but they could also cause more trouble for the environment. The production of solar panels is not exactly environmentally friendly at the moment. The current manufacturing process uses a lot of polluting semiconductors.

An EC-Earth solar farm simulation study shows how this will impact albedo (a concept related to the diffuse reflectance or reflective power of a surface) on local ecosystems.

The study also found that if solar panels covered more than 20% of the Sahara's total area, it could cause a vicious cycle of rising temperatures.

Some of the sun's energy is converted to heat, which can change local temperatures.

Solar panels do not completely convert sunlight into electricity. Instead, some of the sun's energy is converted to heat, which can change local temperatures.

Hot solar panels trigger high surface air temperatures and convection currents, which can cause rain. Increased rainfall will therefore promote vegetation growth, which further reduces albedo, as plants absorb sunlight better than sand.

However, the redistribution of rainfall in the Sahara and surrounding areas would reduce rainfall in the Amazon region by 10-30%. This is roughly the same amount of extra rainfall the Sahara would receive due to the lower albedo caused by the PV panels. The reduction in humidity and rainfall would lead to drought-like conditions in the Amazon.

Not stopping there, solar farms in the desert will promote the development of tropical storms in North America and the East Asian coasts.