Durability of photovoltaic panels: How durable are photovoltaic panels?

From hailstorms to floods, extreme weather events are becoming more common around the world. Therefore, solar companies must take certain precautions to protect photovoltaic equipment and ensure the durability of solar panels in extreme weather conditions.

“We have a choice to build photovoltaic systems that can provide reliable electricity even when extreme weather conditions damage the grid,” said Dirk Jordan, senior reliability engineer at the National Renewable Energy Laboratory (NREL). “The certifications, including education and use of best practices for regional extreme weather, will pay off in electricity savings.”

Solar panel durability includes weather resistance, mechanical strength, equipment longevity, reliability, degradation resistance, equipment warranties and certifications. Let’s review this critical topic so you can better serve your solar customers.

Types of solar panels.

There are many types of photovoltaic modules used in residential and commercial solar energy projects.

Monocrystalline solarpanels are made of a single crystal, usually silicon, and have a black appearance. They are typically efficient modules, but can be more expensive. Monocrystalline panels are generally known for their higher efficiency and longer life compared to polycrystalline panels. This higher longevity is attributed to the structural uniformity of monocrystalline silicon, which results in better resistance to stress and degradation over time.

Polycrystalline solar panels are made of multiple silicon crystals and have a blue spotted appearance. They are generally less efficient and durable than monocrystalline panels, but are often more cost-effective.

Thin-film solar panels use a different manufacturing process, which involves depositing layers of semiconductor material on a substrate such as glass or metal. They can be flexible and lightweight, as well as transparent or translucent. Thin-film panels tend to be less efficient than crystalline panels, but perform better in low-light conditions and at high temperatures. Although thin-film panels have their advantages, they generally have a shorter lifespan and lower durability compared to monocrystalline modules.

Building-integrated photovoltaics (BIPV) are designed to integrate seamlessly with building materials, such as solar roof tiles or transparent solar windows. They serve both to generate renewable energy and as a structural component of the building. The durability of BIPV varies considerably depending on the material and application.

What are photovoltaic panels made of?

Photovoltaic modules are designed to withstand extreme weather conditions such as hail, wind and snow loads. Numerous components help protect the life of the solar cells from moisture, UV radiation, wind, structural damage and other weather-related hazards that can shorten their life.

Solar panels typically consist of the following components:

• Photovoltaic cells are made of semiconductor material that converts sunlight into electricity.
• Hermetization protects the delicate photovoltaic cells from environmental factors and prevents moisture from entering the panel.
• The bottom layer provides electrical insulation and protection from moisture and UV radiation.
• Theframe often consists of aluminum or steel and provides structural support. It protects components from mechanical stress and helps securely mount the panels to the racking system.
• The glass cover is made of tempered glass on the front of the panel to protect it from weather and debris.

Many of these materials and design features increase the solar panels’ durability and resistance to extreme weather conditions. The encapsulation, back layer and glass cover protect the internal components from moisture and UV radiation, which can cause damage over time. The frame ensures structural integrity, while the tempered glass cover provides resistance to hail, wind and other weather-related hazards.

Durability and performance of photovoltaic panels in hot weather.

As temperatures rise, the efficiency of solar panels tends to decrease, resulting in reduced solar energy production. The decrease in efficiency with increasing temperature is primarily due to the behavior of the semiconductor materials in the photovoltaic cells, which can affect both the short-term electricity production and the long-term durability of the solar panels.

The temperature coefficient is used to quantify this relationship and typically uses 25° C as a reference temperature. It represents the percentage decrease in solar panel output for each degree Celsius increase in temperature above 25°C.

The temperature coefficient typically ranges from -0.2% to -0.5% per degree C, but varies depending on the type of solar panel and module quality. Thin-film solar panels tend to have a lower temperature coefficient than monocrystalline and polycrystalline solar panels, so they perform well in hot weather. Similarly, monocrystalline solar panels generally perform better in hot weather compared to polycrystalline panels.

Prolonged exposure to high temperatures can have a degrading effect on the materials used in solar panels, potentially shortening their overall lifespan. Elevated temperatures can lead to thermal stress, causing expansion and contraction of various panel components, which can weaken solder joints and other delicate parts. Over time, such thermal cycles can contribute to the degradation of solar cells and other materials, ultimately affecting the long-term performance and durability of solar panels.

Durability of photovoltaic panels under extreme conditions.

Solar panels are designed to withstand a wide range of weather conditions and can generally perform well under extreme conditions. However, some factors, such as dirt, heavy rain, snow, hurricanes and other harsh weather conditions, can affect solar performance. Proper design, installation and maintenance practices can help mitigate these effects. Please refer to the PVEL photovoltaic module reliability scorecard for information on the performance of specific models.

Dirty photovoltaic panels.

The accumulation of dust, dirt or other particles on the surface of solar panels can reduce the amount of sunlight reaching the solar cells. Dirt can be more pronounced in dry, dusty climates or near industrial plants. In fact, dirty solar modules are more likely to develop hot spots, a common defect in photovoltaic panels that can affect their long-term durability.

To address the problem of dirty photovoltaic panels affecting their longevity, regular cleaning and maintenance is essential. Implementing a scheduled cleaning routine can effectively remove accumulated dirt and debris from the surface of the panels, allowing them to operate at maximum efficiency. Using proper cleaning techniques and equipment, such as soft brushes and non-abrasive cleaning solutions, can help prevent damage to the panels while effectively removing dirt. Critical to the longevity of solar panels, however, is cleaning them safely and avoiding surface scratches.

Rain.

Although rain clouds reduce solar power generation by obscuring sunlight, rainfall can also have a positive effect on the performance of solar panels. Rainwater helps wash away dust and dirt, improving the performance of solar panels. Solar inverters can be sensitive to lightning, so use surge protectors and cover them as much as possible to ensure the longevity of the solar system.

Snow on photovoltaic panels.

Snow accumulation on solar panels poses a challenge because it covers their surface and reduces the amount of sunlight reaching the cells. In regions with heavy snowfall, solar panels are often installed at an angle to help the snow slide off. In addition, photovoltaic modules are designed to be durable and withstand snow loads in accordance with local building codes and standards.

In some cases, periodic snow removal may be necessary to restore optimal performance. However, care should be taken not to scratch the modules, as this may affect the durability of the solar panels. Use a soft brush or snow removal tool designed specifically for solar panels to safely remove snow. In addition, proper precautions are crucial when on the roof, especially if the surface is icy.

Hurricanes and solar panels in high winds.

Solar panels are designed to withstand high wind speeds and are typically tested according to international standards such as the International Electrotechnical Commission (IEC) 61215, a standard that evaluates the mechanical strength of photovoltaic panels by subjecting them to simulated wind conditions. Panels meeting these standards are designed to withstand damage from hurricanes and other strong winds.

Permits for photovoltaic installation in windy climates can meet the requirements of IEC 61215. These requirements are designed to ensure the durability and performance of solar panels in various environmental conditions, including windy climates. However, specific permit requirements may vary depending on local regulations and the severity of wind conditions in a given area.

Flood-prone areas and the durability of photovoltaic panels.

Proper wire routing and electrical installation are critical to ensuring the safety and performance of solar panel systems in flood-prone areas. Electrical components and connections can be designed to be waterproof or housed in weatherproof enclosures. Cable routing is carefully planned to avoid flood-prone areas, and additional measures such as elevated mounting or flood barriers can be implemented if necessary. It is important to follow local building codes and regulations for installing solar panels in flood-prone areas to ensure longevity and safe operation.

Inspection of panels after a weather event.

After a weather event, solar installers should conduct a thorough inspection of the systems for potential damage and longevity issues with the solar panels. Here are the most important steps:

• Ensure personal safety: Before starting the inspection, check for downed power lines or other hazardous conditions. Notify the appropriate authorities and follow proper safety protocols.
• Visual inspection of photovoltaic panels: Please visually inspect photovoltaic modules for visible signs of damage, such as cracks, broken glass or loose connections. Please check that no debris, such as fallen branches, has come into contact with the panels. In addition, please check the panel frame for any signs of bending or deformation.
• Switching off the solar system: If any signs of damage are visible, turn off the entire solar system to prevent any electrical hazards.
• Grounding and wiring: Check the grounding system and wiring connections for loose, corroded or damaged connections.
• Solar panel mounting and racking: Please check the mounting system and rack for signs of movement, damage or misalignment. Please look for loose or missing bolts, brackets or other components and check that the panels are still securely attached to the roof or mounting structure.
• Electrical tests: If a visual inspection reveals no visible damage, electrical tests may be necessary. Please measure the voltage and current output of the panels to ensure that they are within the expected range. Any significant deviation may indicate hidden damage.

Frequently asked questions about the durability of photovoltaic panels.

Here are some of the most frequently asked questions about solar panels in extreme weather conditions.

Are there warranties for solar panels that cover damage caused by extreme weather?

Solar panel warranties typically cover manufacturing defects and performance warranties, not weather damage, as these are subject to external factors beyond the manufacturer’s control. However, warranty terms can vary from manufacturer to manufacturer, so it’s important to consult the specific solar panel manufacturer’s warranty for accurate information.

Homeowners insurance policies often offer coverage for weather-related damage to solar panels as part of their property protection. Please advise your solar panel customers to check with their insurers for solar panel coverage under their policies.

What photovoltaic panels are the most durable in hot climates?

The best solar panels for hot climates tend to have low temperature coefficients to maintain performance. Mono-crystalline panels have a monocrystalline structure, which allows for better heat tolerance and overall performance in hot climates compared to the multicrystalline structure of polycrystalline panels. Thin-film panels and dual-surface panels are also suitable for high temperatures. Please choose panels with a low temperature coefficient for optimal performance in hot climates.

Are photovoltaic panels weatherproof?

Solar modules are designed to be weatherproof and are built to withstand a variety of weather conditions, including rain, snow, hail and high winds. Solar panel manufacturers use materials such as tempered glass and sturdy frames to protect the solar cells from damage. However, proper installation is key to ensuring they are weatherproof, making them suitable for use in a variety of climates and environments.

Can photovoltaic system maintenance increase the life of photovoltaic panels?

Yes, your customers can perform several tasks to prevent weather damage. Depending on the roof and homeowner, you may need to hire a professional to safely perform some of these tasks.

• Please visually inspect the solar panels, racking system and any associated wiring for signs of physical damage, such as cracks, chips, loose connections or exposed wires.
• Please remove any debris such as leaves, branches or dirt from the surface of the solar panels. Accumulated debris can reduce the performance of the panels and ultimately damage them if left unattended.
• Please trim trees near the PV panels, as falling branches or excessive shading by trees can affect the performance of the PV system and potentially cause damage during severe weather.
• Please inspect the roof and mounting system for signs of damage, such as loose or corroded shingles, deteriorating flashings or loose fasteners, if it is safe for homeowners to do so. Address any problems immediately to prevent roof leaks or structural damage.
• Please monitor system output with a solar monitoring system and check inverter readings for unexplained drops in solar output. Please ensure that your customers have the required log-in data to monitor their production data.

Is there any durability test data for photovoltaic panels?

The PVEL Solar Module Scorecard is a reputable source that evaluates the durability of solar panels, as well as other performance indicators. It typically includes data on reliability, performance and other important aspects of solar panels based on extensive testing.

How much wind can photovoltaic panels withstand?

Photovoltaic systems should be designed to withstand wind speeds typical of where they are installed. Standard solar panels can typically withstand wind speeds of 145 to 193 kilometers per hour. However, the specific ratings of solar panels can vary depending on the manufacturer and installation guidelines. In addition, proper installation and mounting of solar panels play a key role in ensuring the safety of the modules in windy conditions.

How durable are photovoltaic panels?

Solar panels are generally durable and designed for long-term use. A glass shell provides protection from environmental factors, while encapsulating materials protect the sensitive photovoltaic cells. The bottom layer acts as an additional layer of protection. Properly manufactured solar panels can withstand harsh weather conditions, temperature fluctuations and UV exposure.

How long do photovoltaic panels last?

Solar panels typically last about 25 to 30 years or more. However, most solar panels continue to produce electricity after 30 years, but at a lower rate due to age-related degradation. Some models of solar panels degrade faster than others, so please refer to the power guarantee for information on the rate of degradation.

Photovoltaic panels are durable and resistant to extreme weather conditions.

Not only are photovoltaic modules designed to withstand extreme weather conditions, but solar batteries can even mitigate power outages caused by such events. For example, tens of thousands of solar PV systems were installed in Puerto Rico after Hurricane Maria. There are best practices that photovoltaic installers and homeowners should follow to prevent extreme weather from damaging photovoltaic systems.

Proper photovoltaic system design promotes durability in extreme weather conditions through features such as robust mounting systems, weather-resistant materials, reinforced structures and advanced monitoring systems that can detect and mitigate potential problems. These design elements ensure that solar systems can withstand harsh conditions and maintain optimal performance for a long time.