The sun of the Sahara Desert is powerful enough to provide Earth with significant solar energy. If the desert were a country, it would be fifth biggest in the world. According to NASA, each square meter of the Sahara receives, between 2,000 and 3,000 kilowatt hours of solar energy per year. With almost no carbon emissions, the Sahara could potentially produce more than seven times the electricity requirements of Europe. Moreover, the Desert also has the advantage of being very close to Europe.
In fact, there are two practical technologies at the moment to generate solar electricity within this context: concentrated solar power (CSP) and regular photovoltaic solar panels.
CSP uses lenses or mirrors to focus the sun’s energy in one spot, which becomes incredibly hot. This heat then generates electricity through conventional steam turbines. This technology seems to be more suitable to the Sahara, but the lenses and mirrors could be covered by sand storms.
A concentrated solar plant near Seville, Spain
Photovoltaic solar panels convert the sun’s energy to electricity directly using semiconductors. But one of the drawbacks is that when the panels get too hot their efficiency drops. This isn’t ideal in a part of the world where summer temperatures often exceed 45 ℃ in the shade. Another problem is that sand storms could cover the panels, further reducing their efficiency.
In addition, both technologies might need some amount of water to clean the mirrors and panels, which also makes water an important factor to consider. Thus, most researchers suggest integrating these two technologies to develop a hybrid system.
Just a small portion of the Sahara could produce as much energy as the entire continent of Africa does at present.
Author: Amin Al-Habaibeh, Professor of Intelligent Engineering Systems, Nottingham Trent University