How to Position Your Solar Panels for Maximum Energy Output

Solar panels are devices that convert sunlight into electricity, and they are becoming more popular as a source of renewable and clean energy. However, the amount of electricity that solar panels can produce depends on several factors, such as the type, quality, and size of the panels, the weather conditions, and the location and orientation of the panels. In this blog post, we will focus on the last factor, and explain how to position your solar panels for maximum energy output.

Why does the position of solar panels matter?

The position of solar panels matters because it affects how much sunlight they can receive and how efficiently they can convert it into electricity. The more sunlight that hits the panels, the more electricity they can generate. However, not all sunlight is equal. The angle and direction of the sunlight can make a big difference in the power output of the panels. At RenewSolar we have gone into years of research in how panels act in the real world and what is the best solutions for the various requirements of our clients.

The angle of the sunlight is determined by the position of the sun in the sky, which changes throughout the day and throughout the year. The sun rises in the east and sets in the west, and it moves higher or lower in the sky depending on the season. The angle of the sunlight affects the intensity and the duration of the solar radiation that reaches the panels. The higher the sun is in the sky, the more intense and direct the sunlight is, and the more power the panels can produce. The longer the sun stays in the sky, the more hours of sunlight the panels can receive, and the more energy they can generate. Simple right?

The direction of the sunlight is determined by the orientation of the panels, which is the compass direction that they face. The direction of the sunlight affects the angle at which the sunlight hits the panels, which is also known as the incidence angle. The smaller the incidence angle, the more perpendicular the sunlight is to the panels, and the more power the panels can produce. The larger the incidence angle, the more oblique the sunlight is to the panels, and the less power the panels can produce.

Therefore, to optimise the power output of solar panels, they should be positioned in such a way that they receive the most intense and direct sunlight for the longest period of time, and that they have the smallest incidence angle with the sunlight.

How to position your solar panels for maximum energy output?

The optimal position of solar panels depends on the latitude of the location, which is the distance from the equator. The latitude affects the angle and the duration of the sunlight that reaches the panels throughout the year. Generally, the closer the location is to the equator, the higher the sun is in the sky in summer, and the more uniform the sunlight is throughout the year. The farther the location is from the equator, the lower the sun is in the sky, and the more variable the sunlight is throughout the year.

The optimal position of solar panels consists of two components: the tilt angle and the azimuth angle. The tilt angle is the angle between the panels and the horizontal plane, and it affects the incidence angle of the sunlight. The azimuth angle is the angle between the panels and the north-south direction, and it affects the orientation of the panels. Lastly there is the Power Curve consideration, this relates to the inverter and power coming from the panels to spread this over the day to lower peak power which can often go to waste on larger system or for summer arrays.

Tilt angle

The optimal tilt angle of solar panels is the angle that makes the panels perpendicular to the sun at noon, when the sun is at its highest point in the sky. This angle varies depending on the latitude and the season of the year. A simple rule of thumb to estimate the optimal tilt angle is to add or subtract 15 degrees from the latitude, depending on the season. For example, if the latitude is 40 degrees north, the optimal tilt angle is 40 + 15 = 55 degrees in winter, and 40 – 15 = 25 degrees in summer. This rule of thumb assumes that the panels are fixed and do not change their tilt angle throughout the year. However, some panels are adjustable and can change their tilt angle according to the season, which can increase the power output by up to 10% ¹. Summer and winter array tilt angle can make a difference of up to 50% in power output.

Another way to estimate the optimal tilt angle is to use online calculators or tools that take into account the location, the date, and the time of the day, and provide the optimal tilt angle for the panels. For example, this tool allows you to enter your address and see the optimal tilt angle for your panels on a map.

Azimuth angle

The optimal azimuth angle of solar panels is the angle that makes the panels face the direction where the sun spends the most time in the sky. This direction varies depending on the latitude and the hemisphere of the location. Generally, the optimal azimuth angle is 0 degrees, which means facing true south in the northern hemisphere, and true north in the southern hemisphere. This is because the sun moves from east to west across the sky, and it is at its highest point in the south or north direction at noon. By facing true south or true north, the panels can receive the most sunlight throughout the day.

However, true south and true north are different from magnetic south and magnetic north, which are the directions indicated by a compass. Magnetic south and magnetic north are affected by the Earth’s magnetic field, which varies depending on the location and the time. To find true south or true north, you need to correct the magnetic declination, which is the angle between magnetic south or north and true south or north. You can use online tools or maps to find the magnetic declination for your location. For example, this tool allows you to enter your address and see the magnetic declination for your location on a map.

Another way to find true south or true north is to use the sun’s position at noon, when it is at its highest point in the sky. You can use a sundial, a stick, or a shadow to mark the direction of the sun at noon, and then align your panels perpendicular to that direction. However, this method is not very accurate, as the sun’s position at noon varies throughout the year due to the Earth’s tilt and orbit. A more accurate method is to use the sun’s position at the equinoxes, which are the two days of the year when the sun is directly above the equator, and the day and night are equal in length. These days are usually around March 21 and September 23. On these days, the sun’s position at noon is exactly true south or true north, and you can use the same method as above to mark the direction and align your panels.

Power Curve Consideration

Power curves are a very common sight in solar production and you will see what you may think is common or standard ( shown in grey). The curves are usually shown by fixed roof solar and for that reason you appear to have the same curve. The green power curve Shows a Solar tracker, this is a fixed system which rotates on a single or dual axis. The results speak for themselves. However the point of split or trackers is to feed the system a equal amount of power through out the day with more linear results.
Fixed installations also have to cater for feast and famine solar in the UK, therefore a winter array will be larger than the summer array as we tend to use more power in the winter and the sun is the weakest against the clouds and the rain, we also have the shorter solar days and the factor between summer and winter is roughly 8 times. In Our test the installation of a winter array proved to be 50% more performance that fixed roof top arrays. if you want to calculate your power output from solar check out the link.

Conclusion

Solar panels are a great way to generate clean and renewable energy, but they need to be positioned properly to maximise their power output. The optimal position of solar panels depends on the latitude, the season, and the time of the day, and it consists of two components: the tilt angle and the azimuth angle. The tilt angle is the angle between the panels and the horizontal plane, and it affects the incidence angle of the sunlight. The azimuth angle is the angle between the panels and the north-south direction, and it affects the orientation of the panels.
Generally, the “Common” position of solar panels is to have a tilt angle that makes the panels perpendicular to the sun at noon, and an azimuth angle that makes the panels face true south or true north, depending on the hemisphere you are reading this in. However, there are online tools and methods that can help you find the optimal position of solar panels for your specific location and date. By positioning your solar panels optimally for your needs, you can increase their efficiency and effectiveness, and enjoy the benefits of solar energy. But you do need to think about when you need the optimal power from your panels. It is far more common for clients to have a east facing array to catch the Early sun and to recharge the battery they were using the night before. Equally West facing for live power when you return home from work and turn things on.