Fast read
Partial shading can impact solar panel efficiency, but it doesn't necessarily make solar energy unviable. Shading reduces the energy production of affected panels, and with traditional systems, one shaded panel can affect others in the same string. However, modern technology, like microinverters and power optimisers, allows panels to operate independently, reducing shading impacts.
The severity of shading depends on factors like the time of day, roof orientation, and shading consistency. A professional assessment with tools like solar pathfinders can help determine how much shading is problematic. In many cases, trimming trees or adjusting panel placement can mitigate shading issues. Overall, solar can still be a viable option even with some shade.
Can Trees or Chimneys Affect Your Solar Panel Performance?
If you’re thinking about installing solar but your roof has some shading—perhaps from nearby
trees, a chimney, or another building—it’s totally reasonable to wonder if it’s still worth it. After all, sunlight is the fuel for your solar system. Even a little shade can raise concerns about performance and payback.
The good news? While shading does affect solar efficiency, it doesn’t always mean solar is off the table Let’s explore how much shading matters, what you can do about it, and how modern technology helps minimise the impact. You’re in the right place to get clear, practical guidance.
Why Does Partial Shading Affect Solar Panel Performance?
Solar panels work by converting sunlight into electricity. So naturally, when part of a panel is shaded, that part produces less power. But what surprises many people is just how much shading can affect the whole system—especially with older string inverter solutions . Traditionally, panels in a string system are connected in series, like Christmas lights. If one panel (or even one cell) gets shaded, it can reduce the output of the whole string. That’s because the current flowing through the entire string is limited by the weakest panel.
Let’s say your system has20 panels in 2 strings of 10, and one is partially shaded by a tree branch in the morning. That one shaded panel could potentially drag down the performance of the other nine in that same string—at least during those shaded hours. While some panels like Aiko has shade tolerance built in the panel – overall it’s simple avoid shade on panels.How Much Shading Is Too Much?
The impact of shading depends on several factors:
- Time of day: Morning or late-afternoon shading is often less serious than midday shade when the sun is strongest.
- Season: Trees may cast more or less shade depending on whether they’re evergreen or deciduous.
- Roof orientation: If your north-facing roof gets some shade in winter but is clear in summer, you might still get excellent year-round production.
- Shading pattern: Consistent, predictable shading (e.g. from a chimney at a certain hour) can often be planned for. Random, moving shade (like leaves fluttering) is trickier.
In practice, some shading is manageable—especially if it only affects a small area for part of the day. But if more than 10–15% of your system is regularly shaded during peak hours, it may be worth considering other options, like adjusting the panel layout, trimming vegetation, or using microinverters or optimiser technology.
Can Technology Help Reduce the Impact of Shading?
Yes, and it’s one of the best developments in solar tech. There are now several ways to minimise shading losses:
Microinverters
Instead of one central inverter for the whole system, microinverters like Enphase go on each panel individually. That means each panel operates independently—so a shaded panel won’t affect the others.
Power Optimisers
These devices, often used with string inverters, “optimise” each panel’s output and isolate any underperforming panels. A well-known brand of this technology is SolarEdge. Like microinverters, they reduce the domino effect of shading.
Solar panel-level Monitoring
Systems with microinverters or optimisers also allow you to see performance panel by panel. This makes it easy to spot if one panel is underperforming due to shade, dirt, or damage.
Bypass Diodes
Modern PV panels have bypass diodes built in. These allow current to “skip over” shaded cells, reducing—but not eliminating—the loss.
Using one of these technologies is a smart move if shading is a concern. While they may cost a bit more upfront, they often pay off in higher generation, with less breakdown via hot spots and better reliability over time.
Should I Cut Down Trees to Improve Solar Performance?
This is a common question—and it depends. Some shading from trees might only affect early morning or late afternoon production, in which case the financial impact could be small. But if a tree consistently blocks the midday sun, it could significantly reduce your system’s output. Here are some things to consider before trimming or removing trees:
- Tree species: Deciduous trees lose leaves in winter, which may help with seasonal sun access.
- Heritage or council rules: Some trees are protected, so you’ll need approval to remove or prune them, and if you remove a tree, make sure you plant many more in another location.
- Aesthetic and environmental value: Trees provide cooling, privacy, and habitat. It’s worth weighing the energy gain against what you’d lose in amenity. Often, a good installer can design around the shade by positioning panels in the clearest areas or using shade-tolerant technology. It’s not always an all-or-nothing decision.
How Can I Know If My Roof Is Too Shaded?
A proper site inspection is the best way. A reputable installer will use tools like solar pathfinders or shade analysis apps to map out shading throughout the year. They’ll look at:
The position of the sun across seasons.
- Shadows cast by trees, buildings, and chimneys.
- Best locations and angles for panels to maximise output.
- This analysis is usually included in a quality quote. If an installer doesn’t offer it—or dismisses your shading concerns—that’s a red flag.
You can also do a basic self-check. Stand on your roof (if safe), or use a drone or a solar app (like SunSurveyor) to see how shadows move during the day. But for a reliable estimate, it’s best to leave it to the professionals.
What’s the Bottom Line on Shading and Solar?
Partial shading isn’t ideal, but it’s not necessarily a deal-breaker. Thanks to smart technology and good design, many homes with moderate shading still achieve strong solar performance. The key is to understand where the shade falls, how long it lasts, and how to work around it.
If you’re not sure how shading might affect your home, a site-specific assessment is the best next step. Your Energy Answers can connect you with trusted local experts who will evaluate your roof honestly and recommend the right system for your conditions—shade and all.
You don’t have to guess. And you definitely don’t have to settle. With the right advice, solar can still be a smart, effective choice—even with a few trees in the picture.
