In an innovative research published in the Journal of Materials Research and Technology, a collaborative research group from Imam Abdulrahman Bin Faisal University in Saudi Arabia and Egyptian universities, has shown the alarming impact of dust, depending on its composition, on photovoltaic (PV) systems in dry coastal environments. The research demonstrated energy losses exceeding up to 48%. This poses serious difficulties with solar energy projects in regions of importance to the global renewable energy transition.

The Study: Unpacking Dust’s Hidden Dangers

A study in Jubail, found on the coast of the Persian Gulf in Saudi Arabia, experimentally assessed how four dust types – montmorillonite, kaolinite, bentonite and natural dust – affected the performance of a PV panel. The experiment featured 20 W polycrystalline PV panel and the experimenters measured power output of the panel as they incrementally added dust to the surface of the panel beginning with dust deposits at 1.0 g/m² and ultimately up to a maximum deposit level of 7.0 g/m². The outcome of the study showed that the composition of the dust, and not just the quantity, caused differences in efficiency degradation across the different types of dust.

Natural dust, characterized by high silica (25.37%) and calcium oxide (30.52%) content, emerged as the most damaging contaminant. At a deposition density of 6 g/m², it caused a 48% power loss by combining light scattering with hygroscopic cementation—a process where humidity transforms loose particles into a hardened layer resistant to natural cleaning. In contrast, montmorillonite, rich in iron (62.67%), contributed to thermal degradation, raising panel temperatures to 40.4°C and reducing open-circuit voltage.

Humidity: The Silent Amplifier

A key insight from the study is humidity’s role in exacerbating dust-related losses. When relative humidity exceeded 60%, efficiency dropped by 15–30%, as capillary forces bonded dust to PV surfaces, creating cemented layers that wind or rain could not remove. Diurnal analysis further showed that PV efficiency peaked during low-humidity morning hours (8:00–11:30 a.m., efficiency 12–13%) but plummeted by 20–25% in the afternoon when humidity rose.

The team also linked air quality to performance declines. At an Air Quality Index (AQI) exceeding 160, combined effects of airborne aerosols and surface soiling reduced conversion efficiency below 10%, even under moderate dust deposition (3–4 g/m²).

Global Implications for Solar Energy

Owing to high solar irradiance, arid coastal zones, such as the Middle East, North Africa, and parts of Asia, are excellent candidates for solar projects. This investigation demonstrated a significant vulnerability to inefficiencies. For example:

• In Qatar, dust accumulation caused monthly power declines of 10–20% on panels tilted at 22°, with unchecked soiling leading to 70% power loss after 234 rainless days.
• In Baghdad, dust densities of 10 g/m² reduced voltage by 26% and short-circuit current by 12%, slashing power output by 34%.

These losses directly increase the Levelized Cost of Energy (LCOE) through reduced output and higher cleaning costs.

Solutions and Future Directions

The research advocates for tailored mitigation strategies. For instance:

• Hydrophobic coatings can combat adhesion in calcium-rich environments.
• Thermal-resistant materials may mitigate iron-induced heating.
• AI-driven cleaning schedules could optimize maintenance based on dust composition and weather data.

The study also aligns with global efforts to address soiling. In Saudi Arabia’s Effat University, DSM launched a desert-specific PV testing initiative, while China’s arid regions are pioneering anti-soiling coatings.

A Call to Action

As the effects of climate change worsen dust storms in arid regions, the research encourages stakeholders to focus on solutions focused on dust. “Finding a connection between dust composition and degradation modes permits us to take specific actions—whether it’s in material science, maintenance, or system design,” the authors stated.

For solar-dependent nations, these findings are a critical step toward securing energy resilience in a dust-prone world.