The Lifespan of a Solar System: What to Expect Over 25 Years

Clerissa Holm • January 29, 2025

 What to Expect Over 25 Years

Investing in solar energy in South Africa is an excellent choice, with over 2,500 hours of sunshine annually in many regions, South Africa ranks among the world’s best locations for solar energy. This abundant resource, coupled with rising electricity tariffs and load-shedding challenges, underscores the growing importance of solar power as a sustainable energy solution. With proper care and maintenance, solar systems can operate effectively for 25 years or more, offering consistent energy savings and reducing reliance on the national grid. South Africa’s unique climate and energy landscape play a significant role in shaping the performance and maintenance needs of solar systems. Here’s what you can expect from your solar system over its lifespan and how to optimise it for South African conditions.

The First Decade: Harnessing the Power of the Sun

South Africa’s high solar irradiance means that solar panels perform exceptionally well during their initial years, with consistent energy output and high efficiency. This period is marked by low maintenance needs and substantial energy savings.

Peak Energy Output: 

The sunny climate ensures optimal solar generation, especially in regions like the Northern Cape and Limpopo and Gauteng.


Minimal Maintenance Needs:

Regular cleaning to remove dust, dirt, and pollen is sufficient in most areas, although drier regions like the Karoo may require more frequent cleaning due to windblown sand and dust.


Warranty Coverage: 

Most panels come with a 10-12 year product warranty and a 25-year performance warranty guaranteeing at least 95% efficiency for the first decade.

South Africa-Specific Tips:

Consider anti-soiling coatings for panels in dusty regions.

Monitor the impact of hailstorms, particularly in Gauteng, and inspect panels for damage after severe weather.

 Years 10-20: Gradual Efficiency Decline

After 10 years, solar panels naturally experience a gradual decline in efficiency due to ageing. However, South Africa’s sunny climate continues to support substantial energy production even as panels age.


  • Efficiency Loss: Expect a 0.5% to 1% annual reduction in output. Panels should retain 85-90% of their original efficiency after 20 years.


  • Component Upgrades: Inverters and batteries may need replacement during this period. In areas affected by load-shedding, investing in high-quality batteries ensures continued energy security.


  • Dust and Dirt Build-Up: Areas with seasonal dryness, like the Highveld winter months, may require more frequent cleaning to maintain performance.



Prolong Performance:

Schedule professional inspections to check for microcracks caused by fluctuating temperatures or hail.

Use energy monitoring tools to detect drops in performance early.


 Years 20-25+: Maintenance and Potential Upgrades

As your solar system approaches its 20- to 25-year mark, it will likely still generate power, though at reduced efficiency. Many South African panels continue to perform well beyond their warranty period, especially with regular maintenance.


  • Efficiency Levels: Expect output to decline to around 75-85% of the original capacity.


  • Consider Upgrades: Advances in solar technology may make upgrading your system a worthwhile investment, particularly for energy-intensive homes or businesses.


  • Durability Factors: The longevity of your system will depend on its exposure to South Africa’s diverse climates, from coastal humidity in Cape Town to the dry heat of the Karoo.


Maintenance for Longevity:


  • Inspect for weather-related wear, including damage from hail, strong winds, and UV exposure in high-altitude areas.


  • Replace mounting structures if signs of rust or wear appear, especially in coastal areas. It is always recommended to use aluminum panel mounting structures to prevent rust and ensure longevity as opposed to steel or galvanized steel structures. 


 Years 20-25+: Maintenance and Potential Upgrades

Maximizing the Lifespan of Your Solar System in South Africa


South Africa’s climate offers unique opportunities and challenges for solar energy. To ensure your system performs optimally throughout its lifespan, follow these best practices:


1. Frequent Cleaning in Dusty Areas: Remove debris and dirt buildup to maintain efficiency, especially in regions prone to windblown sand or prolonged dry spells.


2. Prepare for Weather Events: Use tempered glass panels to withstand hail and invest in durable mounting systems for regions with strong winds.


3. Invest in Energy Storage: Reliable batteries, particularly in areas affected by load-shedding, ensure continuous energy availability during grid outages.


4. Regular Inspections: Schedule professional inspections every few years to detect microcracks, electrical issues, or structural wear.

 Financial and Environmental Returns in South Africa

Over 25 years, a solar system in South Africa offers significant financial benefits by reducing dependence on Eskom and mitigating the impact of tariff hikes. Environmentally, solar power reduces carbon emissions, supporting South Africa’s commitment to sustainability and renewable energy adoption.

 Conclusion

A solar system in South Africa is not just an investment in energy independence but also a step toward environmental stewardship. By understanding its lifecycle and tailoring maintenance practices to South Africa’s climate, you can ensure your system performs optimally and continues to deliver savings and sustainability benefits for decades. By investing in solar energy today, South Africans can reduce their reliance on fossil fuels, combat climate change, and secure a brighter, more sustainable future. Take the first step toward energy independence and environmental responsibility—harness the power of the sun.