Solar Power Plants (PLTS) are an increasingly popular renewable energy solution in Indonesia. However, how does volcanic ash affect solar panels and these systems?
Volcanic ashfall not only covers the surface of photovoltaic (PV) glass but also causes serious consequences, ranging from a drastic drop in efficiency to the risk of long-term physical damage to system components.
Here are some of the effects of volcanic ash on solar power systems:
1. Reduced Efficiency and Power Output due to the Soiling Effect
Volcanic ash settling on solar panel glass creates a barrier that blocks sunlight, a phenomenon known as the "soiling effect."
This dense layer covers the silicon cells inside the panel, significantly disrupting the process of converting photon energy into electrical current.
Ash accumulation obstructs the absorption of direct solar irradiation. A drop in power output occurs rapidly, depending on the thickness of the ash layer.
A volcanic ash layer just a few millimeters thick can slash a solar panel's efficiency and power output by anywhere from 50% to over 80%.
2. Risk of Physical Damage and Component Degradation
The chemical composition and texture of volcanic ash are far more damaging than ordinary environmental dust. Volcanic ash is acidic and hard, with particles featuring sharp edges.
a. Corrosion of Glass and Panel Frames
Volcanic ash contains various acidic compounds, including sulfur and chloride elements. When these ash particles mix with atmospheric moisture or morning dew, the ash layer transforms into a corrosive solution.
This condition can erode the anti-reflective coating on the glass surface and trigger corrosion on the aluminum frames supporting the panels.
b. Abrasion and Micro-scratching
The texture of volcanic ash particles is highly abrasive, as they consist of rock fragments and natural silica glass. Improper manual cleaning methods, such as sweeping ash while it is dry can cause sharp particles to scrape against the glass panels.
This results in micro-scratches that reduce glass clarity and lower the solar power plant's efficiency over the long term.
c. Risk of Hotspots and PV Cell Damage
Volcanic ash accumulation is often uneven across the panel surface, creating localized shaded areas (partial shading).
Cells covered by ash stop generating electric current and instead become a load, absorbing energy from surrounding cells.
This power absorption triggers an extreme temperature spike at a specific point (a hotspot), creating a risk of burning and permanently damaging the PV cell's internal structure.
3. Mechanical Load on Support Structures
Volcanic ash accumulating in areas near an eruption not only obstructs light absorption but also imposes a direct physical load on the solar power installation.
When volcanic ash mixes with rainwater, its density increases rapidly, making it extremely heavy. The accumulation of wet ash across the panel arrays exerts additional pressure—or mechanical load (ash load)—on the support structure (racking system).
If this load exceeds the design capacity, the support frame risks bending or suffering structural failure.
Differences Between Volcanic Ash and Ordinary Dust
The impact of volcanic ash is far more destructive than that of urban dust or ordinary soil dust.
Environmental dust is generally neutral in nature, with fine, rounded particles; consequently, any resulting drop in output occurs gradually, and permanent damage is rare.
In contrast, volcanic ash is chemically acidic (due to sulfur content) and consists of sharp, extremely hard particles. These characteristics allow volcanic ash to cause an immediate drop in electrical output and pose a high risk of damaging the panel's protective glass coating if not handled correctly.
Mitigation Steps for Solar Power System Owners
1. Avoid Dry Cleaning
It is strongly advised not to sweep, brush, or wipe away volcanic ash while it is dry. Direct friction from dry ash will damage and scratch the panel's protective glass.
Ensure that any soap used is not the type that could scratch the solar panels.
2. Rinsing with Low-Pressure Water
Use a medium-pressure water spray to first dissolve and rinse away the layer of ash. Once the ash particles have been fully rinsed off, the panel surface can be gently cleaned using a soft cleaning tool.
3. Periodic System Inspection
After the eruption subsides, conduct a thorough inspection of all supporting components—such as cable conduits, junction boxes, and inverter ventilation vents, to ensure no acidic dust residue has entered and triggered an electrical short circuit.
For technical tasks like this, it is best to hire a technician specializing in solar power system maintenance.
What is the Solar PV Maintenance Frequency During Volcanic Ash Exposure?
Maintenance frequency for solar PV systems during volcanic ash exposure deviates from the standard routine schedule (every 6–12 months); instead, it is based on actual conditions and the specific phase of the volcanic eruption.
1. Active Eruption Phase / Ongoing Ashfall
Visual/Monitoring Frequency: Daily remote monitoring (via dashboard) to track drops in power output.
Physical Action: Deferred (zero interventions until ashfall ceases), unless rinsing the surface becomes unavoidable due to excessive ash accumulation that threatens to overload the structure. Physical cleaning while ash is still falling is ineffective and poses safety risks to technicians due to ash exposure and risk form slipping.
2. Post-Eruption Phase (First 1–3 Days After Ashfall Stops)
Visual Inspection and Rinsing: Once, immediately after ashfall has consistently stopped.
Physical Cleaning (Washing): 1–2 times during the first week. The initial rinse aims to dissolve adhering acidic ash; it is best performed in the morning or late afternoon when panel temperatures are lower to prevent thermal shock.
3. Recovery Phase (1–4 Weeks Post-Eruption)
Electrical & Component Checks: Once per week during the first month.
Inspections focus on cleaning inverter cooling/ventilation filters, physically checking junction boxes, and ensuring no wet ash deposits remain in the gaps of the mounting structures.
Key Indicators for Emergency Cleaning
If the following conditions are observed, cleaning or inspection must be performed immediately, regardless of the scheduled maintenance plan: Output Drop > 20%: A sudden decrease in power output caused by soiling.
Ash Thickness > 2–3 mm: This thickness poses a risk of excessive mechanical load if the ash gets wet from rain. Post-Ash Drizzle: Light rain wets the ash, causing it to harden into a cement-like crust (caking). Cleanup must be performed immediately before this crust dries and hardens.
Emergency Solar Power Plant (PLTS) Maintenance Amidst Volcanic Ash
When volcanic ash is present, do not hesitate to carry out additional maintenance, as the ash can impact the performance and condition of the solar power plant itself.
Ensure that mitigation measures and emergency maintenance procedures are implemented when volcanic ash is spreading in the area. For this maintenance, it is best to engage experts experienced in the care and servicing of solar power plants.
Batari Energy provides solar power plant maintenance services across Indonesia. Do you need maintenance services due to volcanic ash conditions? Click this link for more information!