Generating renewable energy is not about purchasing hardware; it is about knowing the physics of light and geometry. Many users install their system once and then forget about it, losing up to 40% of the potential energy output, in this case just with bad orientation. To make your setup as efficient as possible, it is necessary to actively control the relationship between the sun’s path and the surface of your photovoltaic cells throughout the day.
The position of the sun varies continuously along two axes: azimuth (compass direction) and elevation (height in the sky). A static setup will only capture peak energy for a short period around noon. For the remainder of the day, the angle of incidence is too high, and the photons start bouncing off the glass instead of passing into the silicon cells.
The Physics of Light Capture and Angle of Incidence
To achieve peak performance, the sun’s rays must strike the surface of the solar panel at a perpendicular 90-degree angle. This alignment minimizes reflection and maximizes photon absorption.
When this angle deviates even 15 degrees, the efficiency curve starts to drop. The glass that covers a solar panel is built to be clear in nature but turns reflective at oblique angles. This is like the way a clear lake shows a reflection of the sunset.
Therefore, the main objective of positioning a solar panel is to keep this 90-degree angle of incidence for as many hours as possible. This requires the understanding that the “perfect spot” is a moving target that moves every hour.
Determining True South vs. Magnetic South
Most beginners make the mistake of using a simple compass and pointing their solar panel to the south. However, a magnetic compass displays North compared to True North as per the location you are in the region, the pointing of a magnetic compass may be so far off True North (the location being Magnetic South).
For the Northern Hemisphere, the maximum exposure from your solar panel should face true south. This is the direction of the sun when it is at solar noon. In other areas, the divergence of magnetic from true direction, called the magnetic declination, may be more than 20 degrees.
Should you point your solar panel towards Magnetic South in a place of high magnetic declination, you may well miss some maximum intensity of the midday sun. You can locate the true south where you live with the help of online calculators or special GPS smartphone programs.
Adjusting Azimuth Throughout the Day
While true south is the best compromise for a fixed solar panel, a stationary setup is inherently inefficient. To capture the most sunlight, you should ideally rotate the azimuth of the panel three times a day.
- Morning: Face the solar panel southeast to catch the early rising sun.
- Noon: Realign the panel to true south for peak intensity.
- Afternoon: Rotate the panel southwest to capture the setting sun’s energy.
Calculating the Optimal Vertical Tilt Angle
The horizontal direction is taken care of by the azimuth; the vertical tilt is also vital. The degree of slope of the sun determines the angle at which the solar panel is to lean back.
When a solar panel is lying flat on the ground (0 degrees), it will take sun at noon throughout summer and perform dismally during winter. A vertical panel (90 degrees), on the other hand, loses nearly all the midday summer sun.
The basic guideline of a fixed solar panel is to ensure a lean of the panel is at the same angle as the latitude of where the panel will be installed. This is, however, just a normal average that trades off peak efficiency for convenience.
Seasonal Adjustments for Year-Round Power
During winter the sun is substantially lower in the sky as compared to summer, when it is much higher. A solar panel that is left in the same position throughout the year will experience massive losses according to the season.
During winter you must be able to tilt the solar panel to turn it towards the low sun. This formula is normally your latitude plus 15 degrees. This sharp angle also assists the snow to be removed off the glass, thus keeping it clear of the cells.
In summer, the sun is overhead. The tilt of the solar panel should be flattened to the difference between the latitude and 15 degrees. This enables the cells to take in the high-intensity radiation as it falls on them.
Effects of Mass in the Atmosphere
Atmospheric interference is also countered by the angle of the solar panel. During the morning and late afternoon, the sun’s rays penetrate deeper into the atmosphere of the Earth.
This results in an effect of air mass that occurs in the filtering of energy. You can partially counter this scattering by angling the solar panel at the horizon at these times. Nevertheless, with this density in the atmosphere, even a perfectly directed solar panel will generate less power at 5 PM than at noon.
Optimizing Production in Small Areas and Balconies
The luxury of occupying a 360-degree open roof is uncommon to the apartment dwellers. The installation of a solar panel on a balcony takes more ingenuity and accuracy than one in the backyard.
The smallest problem in such environments is that there is a short span of direct sunlight. You need to determine the so-called prime hours during which your balcony is exposed to unobstructed sunlight. Place the solar panel in a manner that takes advantage of the opportunity to, as much as possible, make use of that period.
In case you cannot put a tripod stand because of space, you can just have the solar panel hanging vertically on the railing. Although vertical mounting does not work best during summer, it does surprisingly well in catching low-angle winter sun or reflections of surrounding buildings.
Utilizing the Albedo Effect
Reflection should be used to increase the amount of light reaching your solar panel artificially. This is referred to as the albedo effect. Light surfaces are those that reflect photons, and dark surfaces are those that absorb photons.
Lay a white rug or reflective sheet on the floor of the balcony facing the solar panel.
The solar panel should be placed close to light-colored walls.
Do not put the panel on black rubber mats or dark asphalt.
These surfaces will provide scattered light to boost your total output up to 5-10% with no additional equipment.
Reducing the Effect of Shadows and Obstructions
The worst enemy of a solar panel is its shadows. Any shadow on the surface that is even 10 percent of the area can decrease the power output by half or more.
This disproportionate decline is because photovoltaic cells are frequently interconnected in series. When one cell is covered by a leaf or a handrail shadow, then this would resemble a kink in the hose and limit the flow of current through the whole group.
You need to scan your surroundings carefully to detect any possible impediments. A drying rack, a chimney or even a power line can create a thin shadow that crosses the solar panel as the sun moves.
Learning about Bypass Diodes
Bypass diodes are frequently incorporated into the modern equipment to reduce the problem. These elements enable the current to avoid the dark area of the solar panel.
Nonetheless, bypass diodes are not magic. They still cause drops in voltages. Physical positioning is the best strategy. In case you have two series units that are interconnected to each other, make sure that the two solar panels do not cast a shadow on the other panel.
Place a stand on the solar panel to lift it out of the ground. This mere elevation usually dissipates the shadows of low-growing grass, rocks, or lips of balcony ledges.
Hardware factors that influence the positioning options
The kind of equipment that you have determines your freedom of positioning. Rigid solar panels weigh a lot as well and are difficult to transport, and the user is typically left with a set-and-forget policy.
A portable or flexible solar panel, conversely, provides the flexibility to follow the sun. This is a great strength in terms of efficiency. It is easy to drag the unit five feet to the left and avoid a shadow of a tree, which is not possible with a roof mount.
The cable length is to be factored in when selecting a spot. A long cable enables the battery station to be in the shade as the solar panel is in the sun.
Temperature and Efficiency
There is a latent aspect of heat in positioning. The higher the temperature of the silicon, the lower the electricity, and the less productive the solar panel.
Airflow: Solar panels must not be put directly on hot concrete or asphalt without separation.
Wind: Have the wind blow past the unit to cool the unit.
Elevation: A kickstand serves to cool the rear of the solar panel.
Working on a Daily Positioning Routine
A solar panel is a living thing that should be part of your everyday life if you want to maximize your yield. It does not require attending to all the time, yet minor interventions give great returns.
Look at things when you drink your morning coffee. Tilt and azimuth the solar panel at lunch. A last rotation that would allow you to recharge your battery is in the late afternoon.
Keep the surface clean. Pollen or urban dust forms an ineradicable shade. Rub the solar panel with a microfiber cloth at least once every few days to clean the glass so that it is optically clear.
Through the accurate angles, seasonal sensitivity, and dynamic shadow control, you can get the maximum possible watts out of your system. The sun is free energy, yet it takes your cooperation to trap it in your solar panel. See more.