Report: Heat and dust reduce solar energy production in sub-Saharan Africa

 energy sub-Saharan Africa 

Report: Heat and dust reduce solar energy production in sub-Saharan Africa

A report by researchers at Arusha Technical College and the Nelson Mandela African Institute of Science and Technology (Tanzania) stated that solar power generation systems suffer significant efficiency losses in sub-Saharan Africa due to extreme heat and dust accumulation.

According to Ecofin, an agency concerned with African financial and economic affairs, the report, entitled "Performance of Photovoltaic Systems in Sub-Saharan Africa under Environmental, Technical and Political Constraints," was based on field analyses conducted in several countries in the region to assess the efficiency losses of solar panels operating under local environmental conditions.

The report, published in the scientific journal "Discover Sustainability," indicated that in sub-Saharan Africa, high ambient temperatures, intense sunlight, and humidity accelerate thermal degradation. These environmental conditions add thermal stress that directly affects the performance of photovoltaic cells.

He added that in many areas south of the Sahara, daytime conditions often cause the surface temperature of photovoltaic modules to rise to over 40 degrees Celsius. These temperatures are significantly higher than those at which photovoltaic systems are designed to operate efficiently.

Several studies indicate that exceeding a surface temperature of 25°C leads to a decline in energy conversion efficiency. These findings mean that performance losses in photovoltaic cells begin even before temperatures reach extreme levels in sub-Saharan Africa.

At the extreme temperatures frequently recorded in the region, the modules can exceed 70°C, significantly reducing open-circuit voltage and increasing recombination losses. Field data confirm that crystalline silicon modules, the most widespread photovoltaic technology, can experience efficiency losses of 15–20% under these thermal stresses.

These losses reduce overall energy production, particularly in off-grid and rural systems where capacity margins are already limited.

Dust accumulation is another problem affecting the performance of solar panels in sub-Saharan Africa, particularly in arid and semi-arid regions. Unlike desert areas, where dust is mostly mineral, the dust found in most of the region contains a higher proportion of organic matter, moisture-trapping particles, and salt deposits.

Without regular cleaning, these layers of dust can block sunlight and significantly reduce electricity production.

The observed productivity reduction ranges from 20% to over 60%. Particle size, tilt angle, and humidity all influence this reduction.

However, the degree of reduction in photovoltaic cell efficiency due to dust accumulation varies considerably depending on the environment. For example, industrial areas characterized by coal dust experience efficiency reductions ranging from 53% to 64%, while dust accumulated from construction sites and mining operations leads to reductions ranging from 58% to 72%