Choosing the Best Solar Panels for Your Home in South Africa: A Guide by EEC’s CEO

To ensure we recommend the best products for solar owners, we conduct rigorous testing at our in-house research facility. Here, we evaluate solar panel technologies under real-world conditions, so you can be confident in the recommendations we provide. We’ve specifically examined three main panel types for their performance in the South African climate:

1. monocrystalline (including enhanced mono PERC),
2. polycrystalline, and advanced
3. heterojunction cell technology.

1. Monocrystalline vs. Mono PERC Technology

• Monocrystalline Panels: These panels are highly efficient, but in South Africa’s high temperatures, they can lose a bit of performance. While excellent in cooler climates, high heat can impact their efficiency.

• Mono PERC Panels: An improvement on traditional monocrystalline panels, mono PERC technology offers a better temperature coefficient, making these panels ideal for hot climates. For homeowners, mono PERC panels are a highly recommended choice, providing better efficiency in our warmer conditions.

2. Real-World Performance Insights

Solar panels are usually rated at standard test conditions (STC), but actual performance can differ when exposed to temperature fluctuations, sunlight angles, and shading. In our testing facility, we found that as temperatures rise, solar panel output can decline. For homeowners, this means selecting a panel with high resilience to heat is crucial for consistent, reliable performance, particularly in off-grid solar applications.

3. Advanced Technology: Heterojunction Cell Technology

For homeowners interested in the latest advancements, heterojunction cell technology combines monocrystalline and thin-film layers, enhancing efficiency even further. Our tests showed these panels capture a broader range of light frequencies, enabling them to perform well in low-light conditions, like cloudy mornings or late afternoons.

• Wider Light Capture: Heterojunction panels excel in capturing light from different angles and under various weather conditions, increasing energy yield even during cloudy days.
  
  
• Superior Temperature Management: With a lower temperature coefficient, these panels remain efficient even in high-heat conditions, a definite advantage in South Africa’s warmer areas.
  
  

Our testing included a comparison of two monoperc panels—one premium model and one budget option—as well as a heterojunction cell technology panel.

Here’s what we discovered:

• The premium monoperc panel showed a 6-8% higher energy yield than the budget option, proving to be a solid investment for clients seeking high long-term returns.
  
  
• The heterojunction cell technology panel excelled with a 15% yield increase over older models. This advanced technology combines monocrystalline and thin-film cells, expanding its ability to capture light across a range of conditions, including low light in early mornings and late afternoons.

For homeowners, it’s essential to choose a solar system that not only lasts but also retains its efficiency. Traditional solar panels come with a 25-year performance guarantee, allowing for up to a 20% efficiency loss. In contrast, new technology panels—like heterojunction—come with a 30-year guarantee and only a 4% efficiency loss, meaning they deliver a much higher long-term return on investment.

While panels with advanced technologies were once significantly more expensive, the price difference today is just 10-15% more than traditional models. This slightly higher upfront investment is offset by increased efficiency, durability, and lower efficiency loss, providing homeowners with long-term energy savings and dependable performance.