The two essential criteria to consider in a solar panel installation project are the panels’ orientation and angle. Orientation refers to the cardinal point facing the sign (north, south, east, west, northeast, etc.); the angle is the slope formed by the panel with the ground (horizontally, vertically or somewhere in between). But, what is the best angle for solar panels? There’s not a definite answer to this question since, depending on the home’s location and the energy needs of its occupants, the optimal angle for solar panels may vary. However, this article will discuss the best angles for solar panels to help the users get an idea of the ideal situation!
What is the Best Angle for Solar Panels?
The inclination is the angle formed by the solar panel and the ground, considered perfectly flat. A panel inclined at 0° is flat against the ground, or horizontal; a 90° panel is vertical, for example, fixed to the front of a building. As the sun’s path varies significantly from one geographic area to another and throughout the year, giving a value for the ideal angle for solar panels is challenging. However, there are general recommendations that will help every consumer make the best choice possible.
The inclination, although mainly expressed in degrees, can also be indicated in percentages. This is relatively rare for solar panels but can happen. Below is a correspondence table to help you find your way around; percentages have been rounded to the nearest whole number.
Best Angle of Photovoltaic Panels
Photovoltaic solar panels generate electricity using solar energy. Their production is maximum when the sun’s rays arrive perpendicularly on the photovoltaic cells; in other words, when the panel in question faces the sun. However, the photovoltaic module produces electricity when exposed to the sun, regardless of the rays’ incidence.
The main problem faced by consumers who want to determine the best angle for solar panels is the same as for orientation- it changes depending on the day of the year and the time of day. We must, therefore, necessarily be satisfied with a compromise, with an average value. The position of the sun in the sky at a given point also depends on the latitude or the position of the place concerning the terrestrial poles. The following formula is generally used to calculate the ideal inclination of solar panels throughout the year:
I = | L | – 10
- I is the inclination to the year expressed in degrees;
- | L | is the absolute value of the latitude, expressed in degrees.
The absolute value of a number is only its numeric part, without a sign (+ or -). In this case, the latitudes are positive in the northern hemisphere and negative in the southern hemisphere; when using the absolute value of latitude, all the “-” signs disappear for the southern hemisphere.
It is this formula that maximizes the production of electricity throughout the year. For people who instead wish to optimize the production of photovoltaic panels in winter, the formula then becomes:
I = | L | + 10
The only area where these formulas do not work is around the equator. In a band of about thirty degrees around this imaginary line, the panels should be laid flat for optimum production all year round. It is rather recommended to give them an inclination of 5° to 10° to ensure that dust and water do not accumulate on the surface.
The same values are valid for installations carried out in America, Asia or Oceania because longitude (east-west positioning of a point on Earth) does not affect the inclination recommended for solar panels. For those who wish to make more precise calculations, tools are available that give usable values from very comprehensive databases for different geographical areas.
Finally, it should be noted that these data are indications that should be used to get an idea of the ideal situation. Still, it is not necessary to follow them to the letter to have a profitable photovoltaic installation.
Best Angles for Solar Thermal Panels
Solar thermal panels do not produce electricity but heat. They are generally used to produce domestic hot water and sometimes to heat a home using a system of hydraulic radiators. The heat produced cannot be sold or stored for long periods. For the installation to be profitable, the thermal panels must operate optimally when the needs are greatest: in winter.
Therefore, the recommended angle for a solar thermal panel is not an average that aims to maximize production throughout the year, but an average of the best inclination over the colder months, in autumn and winter. Thus, the best year-round inclination corresponds to photovoltaic panels for the fall-winter period for thermal panels. The formula is again:
I = | L | + 10
However, there is one exception to this rule: the inclination of the solar panels for heating the swimming pool. This is generally necessary for summer, and the thermal panels that heat the swimming pool can therefore be installed at a slightly lower angle which will take advantage of the summer sun, placed high in the sky.
Best Angle in the Case of Hybrid Solar Panels
Hybrid solar panels are the ones that produce electricity and heat: these are aerovoltaic panels and hydraulic hybrid panels. The question then arises whether they should be installed with the angle of a photovoltaic panel or a thermal panel.
Hybrid solar systems are made up of photovoltaic cells on top, and the heat is recovered below the panels. The production of electricity is more profitable than heat production because it can be sold to benefit from the advantageous purchase price of photovoltaic electricity when it is not consumed. Therefore, we advise individuals to use the optimum inclination for photovoltaic panels for their hybrid panels.
Different mounting brackets are available for different solar panels to get the ideal angle for maximum solar yield. Newpowa Universal Dual Arm Mounting Bracket (ASIN # B07STY9QDX) is ideal for mounting Newpowa solar panel (100-200W) and tilts from 0° to 90°.
Another mounting bracket for achieving the best angles on any flat surface for off-grid solar systems is the Renogy Adjustable Solar Panel Tilt Mounting Brackets (ASIN # B07CSKFWK7) with tilt folding legs.
Our Final Thoughts
We hope the information above must have answered the question, ‘what is the best angle for solar panels’? The ideal angle is essential since it will influence the productivity of the panels. For the best possible results, it is important to consider the two parameters, angle and orientation, simultaneously and not separately. This makes it possible to opt for the best solution!