Solar panels in industrial or agricultural companies, what do you need to know?
The installation of solar panels is not only beneficial for private homeowners. Companies will profit even more from a solar photovoltaic installation. There is great potential, especially for industries or farms with large roof areas or terrain and high energy consumption. As is the case for private households, the investment can be easily amortised by savings in energy costs. In addition, entities that take advantage of “green energy” will be able to value and publicise this fact, transmitting a positive image of sustainability.
Self-consumption helps entrepreneurs and farmers to save money
With the end of the fixed subsidised tariffs for selling energy to the grid and the constant rise in electricity costs, the installation of solar panels has become especially interesting for self-consumption. In UPAC (self-consumption), companies replace part of the energy they usually buy from the grid with a photovoltaic installation for self-consumption. In this way, the local production of solar energy is reflected in a significant reduction in your electricity bill. But, more than that, self-consumption allows you to guarantee a fixed price for the amount of electricity that is supplied by the solar system, which translates into less exposure to the expected rises in energy prices.
Since electricity consumption in industrial companies and farms is usually higher during the day, it is possible to obtain a significant cost reduction, since it is precisely at that time that solar systems produce energy. Nowadays, the investment in a photovoltaic solar installation for self-consumption allows you to recover your investment in periods between 4 and 9 years. So, up to what point is this type of solar panel installation economically worthwhile? It depends on various factors, such as:
- Solar radiation on site
- Energy consumption on site
- Size of the solar photovoltaic installation
- Power of the solar panels installed
- Durability and quality of the system
- Possibility of obtaining a subsidy
Which solar panels should be installed?
There are basically two types of solar panels: polycrystalline and monocrystalline cells. Polycrystalline cells are characterized by having a more irregular surface, which gives them a bluish appearance, and have a lower efficiency than monocrystalline cells. They are normally used in smaller systems in private homes, where space is not a problem. Monocrystalline cells have a regular (dark) colour and a higher efficiency, that is to say, more power for the same area, making them more suitable for larger installations, minimising the necessary areas. In the last few years the technological evolution has allowed the production price of monocrystalline cells to be lower and lower, which means that monocrystalline cells will always be the best option, and they also have a better performance in terms of cell degradation (loss of production) over time and the loss factor with temperature.
Despite the different types, solar panels should always comply with the highest quality standards, norms and certifications. A quality panel has a guarantee against manufacturing defects equal to or greater than 10 years, as well as a power guarantee during its entire useful life (around 25 years). The guarantees are provided by the manufacturers themselves, which is why it is important that they are on the BNEF’s tier 1 list, thus guaranteeing that they are “bankable”, ie, that these guarantees are properly valued by the major world banks.
Where to install solar panels?
Solar systems can be installed on almost any type of roof, or even on the ground.
On flat roofs – with roof slabs with waterproofing or finished with a metallic structure and canvas – since there can be no holes to make fixings, triangular structures are used which are properly ballasted, allowing them to resist the wind, while maintaining all the characteristics and/or guarantees of the original roof. There is the advantage here of being able to make the best adjustment to the direction and angle of inclination of the panels, maximising the radiation received, and consequently the production of the solar system.
In the case of inclined roofs, with tile or sandwich type plates, solar panels are installed directly on the roof by means of hooks (tile) or aluminium supports fixed directly to the plate. A very important aspect, and one which distinguishes the quality of the structure used and the installation itself, is the distance between the roof and the solar panels, in order to ensure good ventilation which will lower the temperature in the cells and consequently reduce production losses.
Alternatively, the solar panels can be integrated into the roof or the facade. With this variant, the panels are flush with the building element and can partially replace it. In the case of a building constructed from scratch, the roof can even consist entirely of solar panels. The main disadvantages of this option are higher costs and a substantial reduction in production, due to the higher operating temperature caused by the absence of ventilation.
Agricultural farms and companies located in industrial areas have the advantage of having large areas of metal (or canvas) roofs available to place the solar panels, or on the ground. On the ground the panels are placed on purpose-built tables which are laid on concrete slabs, or directly on the ground in larger installations.
Cleaning the solar panels ensures better yields
The dirt deposited on solar panels reduces the flow of radiation that reaches the cells and can reduce the capacity to produce electrical energy by up to 30%. Solar panels installed in agricultural or industrial areas need regular cleaning due to the amount of dirt particles in the air, or the presence of aggressive polluting substances. In the agricultural industry, special attention should be paid to the existence of a combination of ammonia, produced by the animals themselves, and dust in the air (typical of rural areas), which leads to the setting of a solid, fairly thick film, which after some time becomes very difficult to clean if it is not done regularly. Furthermore, this ammonia in gaseous state is very aggressive, and can lead to early corrosion of the solar modules.
Therefore, the existing degree of dirt must be well evaluated to better adapt the maintenance plan by a professional team, so that the solar panels can maintain their guarantee and the best possible performance over the years.