Does heat make solar panels perform less efficiently?
Solar panels use sunlight to generate electricity, but high temperatures make them less efficient. As panels get hotter, they produce less power.
If you live in Western Sydney, Queensland, South Australia, or anywhere that often hits 35°C or higher in summer, this really matters. It can affect which panels are best for your home.
At PSC Energy, we install solar systems in Western Sydney, where summer roof temperatures can reach 60 to 65°C. We’ve seen how different panels perform in these conditions and know there’s often a gap between manufacturer claims and real-world results.
In this article, you’ll learn about the following:
- Why Heat Is the Enemy of Solar Output
- Temperature Coefficient: The One Number That Actually Matters
- How the Main Panel Technologies Compare in Heat
- Best Solar Panels for Hot Weather Australia (2026)
- How Much Does It Matter Terms of Dollars?
- What to Look for When Comparing Quotes in a Hot Climate
- FAQ: Solar Panels in Hot Weather in Australia
By the end of this article, you’ll understand how heat affects solar output, which specs matter most, and which panels we recommend for hot Australian climates.
Why Heat Is the Enemy of Solar Output
This surprises many people. Australia gets plenty of sun, so it seems like solar panels should work perfectly. But solar panels generate electricity from light, not heat.
More sunlight helps, but more heat does not.
When a panel gets too hot, its electrical resistance increases. This lowers the voltage and reduces the amount of power the panel can produce.
On a 35°C day, panels on your roof can reach 60 to 65°C. At these temperatures, most standard panels produce far less power than their rated output.
This problem is bigger in Australia than in most other countries. In places with mild summers, heat loss is minor. But in cities like Penrith, Parramatta, Brisbane, or Adelaide, it happens many times each year.
If you’re interested in learning a bit more about how weather affects solar panels, you might want to check out the following article titled, How Does The Weather Affect Your Solar Panels?
Temperature Coefficient: The One Number That Actually Matters
Every solar panel datasheet lists the temperature coefficient of power. This number shows how much output the panel loses for each degree above 25°C, which is the standard test temperature.
Here’s how that works in practice:
- A panel with a temperature coefficient of -0.35%/°C loses 0.35% of its rated output for every degree above 25°C.
- If a panel reaches 65°C, which often happens in Australian summers, it can lose about 14% of its output.
A lower (less negative) temperature coefficient means the panel performs better in heat. Here’s a quick comparison by technology type:
- Standard TOPCon panels: -0.28% to -0.35%/°C
- HJT (Heterojunction) panels: -0.24% to -0.26%/°C
- ABC (All Back Contact) panels: -0.26%/°C
The difference between -0.35% and -0.26% might seem small, but over many hot days each year and a 25-year system life, it adds up to a lot more power.
If you’re interested in learning a bit more about solar panel efficiencies, you might want to check out the following article titled, How Efficient Are Solar Panels? Shade, Heat, and Seasonal Considerations in NSW, Australia.
How the Main Panel Technologies Compare in Heat
There are three main types of solar cell technology available in Australia. Here’s how each one handles heat.
TOPCon
TOPCon (Tunnel Oxide Passivated Contact) is the most common technology in today’s mid-range and budget panels. It’s a step up from older PERC technology and works well in normal conditions.
In hot conditions, TOPCon panels perform adequately but not exceptionally. Their temperature coefficients usually range from -0.28% to -0.35%/°C, depending on the manufacturer. TOPCon is a solid choice for most Australian homes, but it’s not the best in very hot climates.
HJT (Heterojunction Technology)
HJT panels use both crystalline and amorphous silicon to reduce electrical losses in hot weather. Their temperature coefficients are usually between -0.24% and -0.26%/°C, so they handle heat better than most. REC’s Alpha range is the best-known HJT panel in Australia. These panels are usually more expensive.
ABC (All Back Contact)
ABC panels place all their electrical connections on the back of the cell, so there are no metal bars blocking light on the front. This improves both efficiency and heat performance. Aiko’s Gen 3 ABC panels have a temperature coefficient of -0.26%/°C, similar to top HJT panels. They also run about 30% cooler than TOPCon panels at hot spots, which helps them last longer.
If you’re interested in learning a bit more about solar panel problems and solutions, you might want to check out the following article titled, 4 Common Solar Panel Problems (and How to Avoid Them).
Best Solar Panels for Hot Weather Australia (2026)
Here are the three panels we recommend for homeowners in hot parts of Australia, along with the reasons why.
1. Aiko Gen 3 ABC — Best Overall for Hot Climates
- Temperature coefficient: -0.26%/°C.
- Output: 535 to 550W per panel.
- Module efficiency: up to 25%.
- Warranty: 25-year product, 30-year performance guarantee.
- Long-term output: retains 90.6% after 30 years.
- Degradation: ~1% in year one, then 0.35% per year.
- Hot-spot temperature: 30% lower than comparable TOPCon panels.
- CEC approved: March 2026.
Aiko won the 2025 SolarQuotes Installers’ Choice Award for best solar panel in Australia, as voted by 161 working solar installers. Their Gen 3 ABC panels are the newest in the range, approved by the Clean Energy Council in March 2026 and available from late April 2026.
The temperature performance is impressive. A -0.26%/°C coefficient and lower hot-spot temperature mean these panels truly outperform standard TOPCon options on hot days, not just in theory. The 25% efficiency rating also means you need fewer panels for the same system size, which is helpful if your roof has limited space.
2. REC Alpha Pure RX — Best Premium Option
- Temperature coefficient: approximately -0.24%/°C (HJT technology).
- Output: up to 470W per panel.
- Warranty: 25 years of product and performance.
- Technology: HJT (Heterojunction).
REC is a premium panel brand with a strong track record in Australia. Their Alpha Pure RX uses HJT technology, which performs very well in hot conditions. With a temperature coefficient of about -0.24%/°C, they are leaders in heat performance.
REC panels cost more than Aiko or Jinko. A 10kW system with REC Alpha panels usually costs $12,000 to $14,000 installed. If you want the best heat performance and are willing to pay extra, REC is a great choice. They’re also highly rated for coastal areas, where salt air can be tough on panels.
3. Jinko Tiger Neo — Best Value Option
- Temperature coefficient: approximately -0.29%/°C (TOPCon technology).
- Output: up to 440W per panel.
- Warranty: 25 years of product and performance.
- Technology: N-type TOPCon.
Jinko is one of the most widely installed solar panel brands in Australia. The Tiger Neo range uses N-type TOPCon cells, which handle heat better than older P-type panels. A temperature coefficient of around -0.29%/°C is good, though not as strong as Aiko or REC in hot conditions.
Jinko’s biggest advantage is value. A 10kW system with Jinko panels usually costs $9,000 to $11,000 installed, which is much less than REC and similar to Aiko. If you’re on a budget but still want a good panel, Jinko Tiger Neo is a solid choice. Just make sure you pick a quality installer, since some companies use Jinko’s name to cut corners elsewhere.
If you’re interested in learning a bit more about solar panels and energy systems, you might want to check out the following article titled, Are Solar Panels Worth It in NSW, Australia? A Price Breakdown for 2026.
How Much Does It Matter Terms of Dollars?
Here’s a worked example. Consider a 10kW system in Western Sydney, a location that regularly hits 38-42°C in summer.
Assumptions:
- Panel surface temperature on a hot day: 65°C (40°C above the 25°C test condition).
- The system generates 40kWh/day in peak summer.
- Feed-in tariff: $0.05/kWh; self-consumption saves $0.30/kWh.
At 65°C panel temperature, here’s the approximate output reduction by technology:
- Standard TOPCon (-0.35%/°C): 14% loss = output drops to ~34.4kWh/day
- Aiko/REC (-0.26%/°C): 10.4% loss = output drops to ~35.8kWh/day
That’s about 1.4kWh more each day from the better panel. It might not seem like much for a single day, but over 60 to 80 hot days a year in Western Sydney, it adds up to 85 to 115kWh more each year. At about $0.20 per kWh, that’s $17 to $23 extra per year.
In short, the hotter your climate and the more hot days you have each year, the more important the temperature coefficient is.
What to Look for When Comparing Quotes in a Hot Climate
When you get solar quotes, most of the focus is on system price and panel brand. Here’s what you should check if you live in a hot region:
- Temperature coefficient: Check this number on the datasheet. Anything better than -0.29%/°C is good, and -0.26%/°C or better is excellent for hot climates.
- N-type vs P-type cells: N-type cells, found in modern TOPCon, HJT, and ABC panels, last longer in the heat than older P-type (PERC) cells. Make sure your panels use N-type cells.
- Hot-spot temperature: This isn’t always on the standard datasheet, but it’s worth asking about. Lower hot-spot temperatures mean less thermal stress on the cells over time.
- Warranty terms: Look for a 25-year product warranty and a performance guarantee. Check the yearly degradation rate, not just the final number. For example, a panel that keeps 90.6% of its output after 30 years (like Aiko) is better than one that only promises 80% at year 25.
- Installer quality: Even the best panel won’t work well if it’s not installed properly. Ask if the company uses their own electricians or subcontractors, and check their reviews.
Wrapping Up: Hot Roof, Cool Returns
Solar panels work harder in Australia than in most other countries. The strong sun makes solar a great investment, but the heat puts extra stress on your panels. Choosing a panel with a low temperature coefficient, N-type cells, and a solid warranty helps your system deliver its rated output when it matters most.
PSC Energy installs solar systems throughout Western Sydney and understands what Australian conditions demand from solar panels. If you’d like advice tailored to your roof, location, and energy needs, contact our team for a free quote. It’s what we do.
If you’re interested in learning a bit more about weighing the cost of solar against the cost of the grid, you might want to check out the following article titled, Cost of Solar Panels vs. Cost of Energy from the Grid.
FAQ: Solar Panels in Hot Weather in Australia
Do solar panels lose efficiency in hot weather in Australia?
Yes. Solar panels are tested at 25°C. In the Australian summer, panel surface temperatures often reach 60-70°C. That additional heat reduces voltage and drops output. The amount of loss depends on the panel’s temperature coefficient.
What is the best temperature coefficient for solar panels in a hot climate?
Look for a temperature coefficient of -0.26%/°C or better. HJT and ABC technology panels typically achieve this. Standard TOPCon panels sit around -0.29% to -0.35%/°C.
Are Aiko panels good for hot climates?
Yes. Aiko Gen 3 ABC panels carry a temperature coefficient of -0.26%/°C and run 30% cooler at the hot-spot level than comparable TOPCon panels. They’re among the strongest-performing panels on the Australian market in hot conditions.
Do solar panels work better in winter or summer in Australia?
Panels often produce more power per day in summer due to longer daylight hours and stronger sunlight, despite heat loss. But efficiency per hour of sunlight is actually higher on mild sunny days than on extreme heat days, because heat reduces output.
Are there solar panels specifically designed for hot climates?
No panel is made exclusively for hot climates, but some technologies handle heat significantly better than others. HJT and ABC panels are the best current options for heat performance. Both Aiko and REC offer strong choices in this area.
Is it worth paying more for panels that perform better in heat?
In a hot climate like Western Sydney, Queensland, or South Australia, yes — particularly if your system is large or you plan to own the home long-term. The extra output on hot days adds up over a 25-year system life.
