If you have a house with roofs with several falls and you are interested in the placement of solar panels in this article we will analyze this topic. In the case of photovoltaic installations placed on roofs, the following play a very important role: the angle of the sun’s rays, the position of the roof in relation to the directions of the world, the shadow and whether it is a complicated roof.
Photovoltaic energy on a complicated roof
Of course, the best thing is if the roof we want to use for the photovoltaic installation is gabled, has an optimal slope and is oriented to the south. If we are only planning to build a house, we have the opportunity to optimize these parameters. However, what to do in a situation where our house is already built, but its roof is unfortunately complicated in the context of the location of the photovoltaic panels? We will try to answer this question step by step.
Is my roof suitable for a photovoltaic installation?
However, before answering these questions, we must begin our considerations with the answer of whether my roof is suitable for photovoltaic installations. To do this, you need:
- determine the position of the ceiling in relation to the directions of the world;
- analyze the roof structure: determine the number of drops, bends, determine where the chimneys and roof windows are located;
- analyze shading. So where and for how long the shadow will fall on the installation, it will also be useful to analyze the area. And if there are trees or other buildings around the house that can shade the roof significantly;
- Determine the angle at which the panels will be located, preferably 20 to 40 degrees for a sloped roof and 10 to 15 degrees for a flat roof.
In addition, photovoltaic panels can be used on any roof, except asbestos, ondulin, polycarbonate and plexiglass.
Complicated roof – what is it?
What kind of roof can be called complicated in the context of the installation of photovoltaic installations on it? We are talking mainly about roofs characterized by a complicated structure. These are hipped roofs with numerous dormers, roof windows or chimneys. In many cases, the flat surfaces of such roofs may not be sufficient to install photovoltaic panels on them.
In addition, most of these roofs may have a northern exposure, be in the shade, or for other reasons the roof may not be suitable for the use of photovoltaic installations.
Photovoltaic installation on a complex roof – options available
If the roof has a complex structure, but the total area of the roof allows the installation of photovoltaic panels, we have several options to make the photovoltaic installation effective.
In such cases, however, string inverter-based facilities cannot be used. In the case of these mechanisms, the individual panels are connected to each other in series, and the direct current produced by the modules is jointly converted into alternating current by means of an inverter: each panel of the installation works with the power of the weakest link.
The use of inverters with multiple systems for monitoring the maximum power point, the so-called MPPT
MPPT, or Maximum Power Point Tracker, is an electronic system that tracks the maximum power point of solar modules. It allows you to optimize energy production from a few to a dozen percent. In the case of complex roof structures, an inverter with several independent MPPT inputs should be used. This makes it possible to mount photovoltaic modules on several different roof slopes.
Microinverters are smaller and safer inverters . They are an increasingly used solution because they allow each of the panels connected to each other in a chain to work more efficiently.
Stilo Energy currently offers devices that support up to four panels. Thanks to the use of these devices, neither panel connected to each other in a chain does not affect the other. In addition, despite connecting 4 panels to a microwave oven, we can monitor individual panels (their production, operation, etc.). How is it possible? Each microinverter has its own MPP tracker. In such a solution, the entire process of converting light energy into electricity is carried out in the module.
Application of an inverter with power optimizers
In the case of a roof that is not multi-pitched but with shading elements, it is possible to use a central or string inverter and power optimizers. Optimizers are electronic devices that control and optimize PV modules (most of the time, a single optimizer supports 1 or 2 modules). As a result, it is capable of producing the maximum amount of energy in all conditions.
They are used, for example, for selected modules that are shaded during certain periods of the day or year. To optimally select such a solution, a shading analysis is carried out using professional programs to design photovoltaic installations. Using energy optimizers allows you to get a few to a dozen higher percentages of electricity performance from your installation.
A complicated roof is not an obstacle!
Even roofs with very complex structures – of various heights, with skylights, dormers or chimneys – can be the basis for photovoltaic installations. Please note that not all roofs can be equipped with photovoltaic systems. However, if it is not possible to install a solar photovoltaic system on the roof and there is enough land available, there are no obstacles in deciding to install a photovoltaic system on the ground. Stilo Energy specialists will help you choose the optimal solution for your property conditions.