North-south or east-west? Solar panel orientation explained
Solar panel orientation is a pivotal aspect of solar power system design, directly influencing the efficiency and energy output of the panels. In the Australian context, where significant amounts of energy can be generated from the sun, understanding and optimising the orientation of solar panels is particularly important for homeowners. In the Southern Hemisphere, the main panel orientations to consider are north-south and east-west, each with its unique advantages and implications.
Choosing the right orientation for solar panels ensures they capture the maximum amount of sunlight over the course of a day and throughout the year. This decision impacts not only the energy yield but also the overall cost-effectiveness of the solar power system.
The northern orientation
The northern orientation aligns the panels to face directly towards the north. This setup is particularly effective in the Southern Hemisphere, as it allows panels to capture the most direct sunlight during the middle of the day when the sun is at its highest point.
The primary benefit of northern orientation is its ability to maximise solar energy production during peak sun hours. This period, typically from late morning to early afternoon, is when the sun is at its highest point in the sky, providing the most direct and intense solar radiation. For households with high energy consumption during these hours—perhaps due to air conditioning use, home offices, or other daytime activities—aligning panels in a northern direction can be particularly advantageous. This orientation harnesses the sun's energy most effectively when it is most needed, reducing reliance on the grid and potentially lowering electricity bills. It is especially beneficial during the summer months when the days are longer and the sun is higher in the sky, leading to extended periods of peak energy production.
Potential considerations
Local environmental factors may also play a significant role. Potential shading from surrounding buildings, trees, or other structures can significantly impact the amount of sunlight reaching the panels. Even small amounts of shade can reduce the efficiency of solar panels, making it crucial to consider the immediate surroundings when planning the installation.
In urban environments where buildings are densely packed, the potential for shading is higher, and the optimal orientation might shift slightly to avoid shadows cast by nearby structures. Similarly, in suburban or rural areas with abundant vegetation, the growth and movement of trees throughout the year can create dynamic shading patterns that need to be considered.
If shading of your panels is a concern, SolarEdge’s market-leading Power Optimisers can boost production at the panel level, ensuring that if one panel is affected by shade, the rest of the system is not compromised, unlike a traditional string system without optimisers. Learn more about our Power Optimisers here.
East-west orientation
East-west oriented solar panels, uniquely positioned to face the rising and setting sun, offer a distinct advantage in harnessing solar energy during the early morning and late afternoon. This orientation is particularly beneficial for households with energy consumption patterns that align with these times. For example, families preparing for the day in the morning or returning home and using electrical appliances in the evening can draw directly from the solar energy generated during these periods.
Extended duration of generation
While east-west oriented panels may not capture as much direct sunlight as the northern
orientation during the peak solar hours around midday, they offer a prolonged period of energy generation. Starting from the early morning, as the sun rises in the east, these panels begin capturing solar energy, continuing through to the late afternoon as the sun sets in the west. This extended duration of energy generation can be particularly useful during the shorter days of winter when the sun is lower in the sky.
In urban settings, where roof space is often limited and homes are frequently built along an east-west axis, this orientation becomes even more advantageous. The east-west alignment allows homeowners to maximise the use of their limited roof space, capturing solar energy from sunrise to sunset. This can be especially beneficial in densely populated areas where the orientation of buildings and available space may not accommodate the ideal north-oriented solar panel setup.
Balanced energy production
East-west oriented panels can offer a more balanced energy production throughout the day, aligning better with the typical energy usage patterns of many households. Instead of producing a large amount of energy in a short period around midday (which might not be fully utilised and thus exported to the grid), these panels provide a more consistent supply of energy throughout the daylight hours. This consistent generation aligns well with homes that have a steady consumption of electricity during the day, leading to more efficient use of the energy produced and potentially lower electricity bills.
This orientation can also be a strategic choice for homes that participate in net metering schemes. Since east-west panels produce electricity more evenly throughout the day, they can reduce the amount of energy drawn from the grid during peak hours, which are often more expensive. This can lead to additional savings and a more cost-effective use of solar power.
Sun movement and its impact
The sun’s trajectory, both daily and seasonally, significantly influences the efficiency of solar panels. During summer, the sun takes a higher path across the sky, leading to longer daylight hours and more intense solar exposure. In winter, the sun’s lower path results in shorter days and less intense sunlight. For north-oriented panels, this means a significant variation in energy production between summer and winter. East-west oriented panels, however, tend to have a more consistent output throughout the year, though they may produce less total energy compared to their north-oriented counterparts.
Efficiency and energy production comparison
The efficiency of solar panels is greatly influenced by their orientation. North-oriented panels typically achieve higher peak efficiency, particularly during the summer months when the sun is high in the sky. However, their energy production can drop significantly during winter.
East-west orientations, while having slightly lower peak efficiency, provide a more consistent level of energy production throughout the day and across different seasons. This can be particularly beneficial for balancing energy production with consumption patterns, leading to more effective use of the generated solar power.
Factors influencing orientation choice
Choosing the optimal orientation for solar panels involves considering several key factors:
- Local climate conditions: The amount of sunlight and its intensity can vary greatly depending on the geographical location. Areas with higher sunlight intensity may benefit more from northern orientations.
- Energy consumption patterns: Households with peak energy usage in the morning and evening may find east-west orientations more beneficial, while those with midday peaks might prefer northern alignments.
- Roof design and space: The shape and size of the roof can limit the orientation options. In some cases, a combination of both orientations might be the most effective solution.
- Aesthetic preferences: The appearance of solar panels can be a significant consideration for some homeowners, as the choice of orientation can affect how the panels look on the roof.
With real-time performance monitoring and management, you can see how your panels perform across multiple roof orientations. When integrated into a full SolarEdge system, the mySolarEdge app allows homeowners to observe how different orientations affect their energy production throughout the day and across seasons. This data can be invaluable for assessing how your panels are performing through the day and if they are producing enough power to cover your current energy needs. Detailed insights into daily and seasonal energy output can also guide homeowners in aligning their solar panels optimally with the sun’s path. Learn more about this innovative tool and how it can enhance your solar system's performance here.
Key takeaways
- North orientation is most effective in midday sun. It’s ideal for homes with high daytime energy use, though effectiveness may vary with location and shading.
- East-west orientation suits homes with morning and evening energy peaks, offering extended energy generation and a more balanced daily output.
- Optimal panel orientation depends on local climate, energy needs, roof design, and aesthetics, sometimes necessitating a combination of both orientations.
- Performance monitoring can optimise performance, by allowing you to see how your panels are performing on different roof aspects at different times of the day.
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Considering adding a solar system to your home? SolarEdge offers market-leading technology across panels, inverters, optimisers, and storage and backup solutions. Learn more about our range of residential products here, or to find an installer in your area, click here. Got a question or a comment? Get in touch with us now.
