hotovoltaics has proven a popular choice with homeowners wishing to switch to green energy. However, one should keep in mind that harvesting sunlight is a bit more complicated than simply drawing power from the grid. The performance of a PV system depends on numerous factors, one of them being the tilt of your modules.
It might seem to you that defining the best solar panel angle is no easy feat. This article breaks down how to calculate your optimum solar panel angle with no effort.
Angle for solar panels: two basic types
When it comes to solar panel angle and its calculation, it must be noted that there are two different parameters referred to in this regard: the first one is the azimuth, and the second one is the tilt. Firstly, we will find out what both terms mean to avoid confusion. Below, you will learn how to calculate these values for your photovoltaic panel system.
Azimuth solar panel angle
In basic terms, the azimuth solar panel angle, or “azimuth” for short, refers to the cardinal direction (in other words, “orientation”) your photovoltaic panels face, which is north, east, west, or south.
To be more precise, the azimuth solar panel angle is basically an angle that describes the position of photovoltaic panels with respect to the north. According to the definition itself, the azimuth angle for solar panels is 0° when the sun is north of PV panels. Correspondingly, it is 90°, 180°, and 270° for the east, the south, and the west.
Tilt solar panel angle
The tilt, otherwise known as the “elevation/altitude angle of solar panels,” is the vertical inclination of your photovoltaic panels. When a PV panel lays on the ground, it has no tilt. If it is standing perpendicular to the ground, the tilt is 90°. The lower the tilt is, the more “up” towards the sun your photovoltaic panels face.
Calculating the optimal solar azimuth
If you are willing to minimize the loss in solar efficiency, your panels should face toward the Equator. The closer to the Equator the photovoltaic panels are positioned, the more direct sunlight they will receive throughout the day, and, as a result, the higher their performance will be.
That means south for all of us living in the Northern Hemisphere. In case you live in the Southern Hemisphere, that means north. So, once again: if you are, for example, located in the United States, the best angle of solar panels is definitely the one directly true south. For those who live below the equator, like Australians, it will be true north.
Are you wondering why we added the word true? By calculating the optimal solar panel orientation, you should be aware that there is a difference between magnetic north, shown by your compass, and true north! A compass needle points to the magnetic north, not the geographic north, and the deviation between these two measurements is called “magnetic declination.”
To find out the difference between true north and magnetic north at your location, use one of the available magnetic declination calculators. For instance, if you live in Los Angeles, California, your magnetic declination is about 11° east. In case you are from Melbourne, Australia, your magnetic declination is also about 11° east.
Knowing your magnetic declination, how can you define the optimal angle for solar panels? Well, without much effort. Since Los Angeles, California, is located above the Equator, find your magnetic south and adjust your photovoltaic panels 11° to the east. By figuring out the optimum solar panel orientation in Melbourne, Australia, find your magnetic north and adjust your PV panels 11° to the west. Thus, you will be able to get the most out of your solar power production.
Solar energy has become cheaper than fossil fuels in many regions, thanks to technological advancements, declining solar panel costs, and increased efficiency.
Calculating the optimum tilt for your solar panels
The tilt solar panel angle calculation receives so much attention because your photovoltaic panels will obviously produce maximum solar energy when they are pointed directly at the sun. Let’s check what factors influence the photovoltaic panel’s tilt.
How does your latitude affect the solar panel inclination?
The latitude of your location plays a crucial role in defining the tilt angle for solar panels. If you plan to achieve the best solar energy production and have no desire or capability to adjust the mounting of your panels, the optimal solar panel angle should be equal to your location’s geographical latitude. For example, for a photovoltaic panel system mounted at a latitude of 50°, the optimum solar panel mounting angle would also be 50°.
Basically, you can find the optimum angle for solar panels by doing a Google search for the latitude of your home address (typically, by your ZIP code) and fixing the tilt once and for all. But more is needed if you are determined to squeeze the most out of your installation. The thing is, the proper solar panel angle will change over the course of the year.
Should you tilt your solar panels seasonally?
It is easiest to mount your photovoltaic panels at a fixed tilt and not to adjust the inclination. However, given that the sun is higher in the summer and lower in the winter, you can capture more energy during the whole year by adjusting the tilt angle of solar panels according to the season.
As a general rule, the tilt should be adjusted twice a year. For warmer months (in summer), it will be 10-15 degrees minus your latitude. The ideal solar panel angle for cooler months (in winter) will be 10-15 degrees added to your latitude.
Due to the fact that the best angle for solar panels changes from summer to winter, photovoltaic panels are usually installed at an angle that will balance the needs of both seasons, especially when a solar system owner is not ready to adjust them. For instance, panels in Miami, Florida, are typically tilted around 25°, as the ideal summer tilt is closer to 10°. In comparison, the ideal winter tilt is closer to 40° degrees, so the 25° tilt is a compromise between the two.
Do you need to change the tilt of your solar panels during the day?
Of course, the sun is continually moving not only throughout the year but also throughout the day. In order to get the best from your equipment, each panel in a photovoltaic system should ideally track the sun minute by minute to achieve the maximum possible energy output. Unfortunately, such tracking systems are often too expensive to implement in a residential household. It is usually more reasonable to figure out the optimal parameters based on the knowledge about magnetic declination (for orientation) and latitude (for tilt) than purchasing a tracker which automatically adjusts the angle for solar panels according to the sun’s position in the sky.
Does your roof affect solar performance?
Actually, comparisons between a shallow 15-degree inclined roof and a steep 45-degree inclined roof show little power production difference. Overall, the amount of energy generated evens itself out across the seasons. A shallow roof captures more sunlight during summer, and a steep roof captures more sunlight during winter. Therefore, the inclination of your roof has little impact on annual panels performance and can hardly be considered a defining factor in your system output.
So is it essential to find the best angle for solar panels, after all?
If you have decided to install a PV panel system, you can use a solar panel angle calculator to figure out the ideal solar panel angle. Photovoltaic providers have a bunch of such tools available on the Internet. There is no angle for solar panels calculator cannot determine, but is it worth paying such attention to finding the panel's optimal azimuth and tilt? Our answer is yes.
Photovoltaic panels don’t have to be south-facing, so if your roof doesn’t face south, this doesn’t mean you can’t go solar. Nevertheless, you will get the most output from a south-facing panel system (if you live in the Northern hemisphere). Your panels don’t need to have the same inclination as the latitude of your home, but if they do, you will receive the maximum average result from your photovoltaic panel system year-round. To summarize, solar panel angle is particularly important for your panel system.