Solar Panel Efficiency continues to increase year by year with developing technology. As new generation solar panels emerge, panel efficiency also increases. The average solar panel efficiency for 2024 is between 15% and 25%.
So what is this solar panel efficiency? Why is solar panel efficiency important? How does it affect the solar energy system? Let’s look for answers to these questions together.
What is Solar Panel Efficiency
Solar panels consist of solar cells that convert the sunlight falling on them into electricity. Solar cells convert solar energy into electrical energy in proportion to their efficiency. When a solar panel with 20% efficiency is mentioned, it means that it converts 20% of the sunlight falling on it into electricity.
A value such as 20% may seem low for solar panel efficiency. The efficiency of power plants that convert fossil fuels into electricity is around 60%, but these power plants use fossil fuels as raw materials and this has a cost. It is completely free with solar energy and the free energy is converted into electrical energy with 20% efficiency.
Therefore, every increase in efficiency means big profit. Below are the efficiency values for different solar panel types.
| Type of solar panel | Efficiency (%) |
|---|---|
| Monocrystalline | 15-20% |
| Polycrystalline | 15-17% |
| Thin-film | 15-20% |
For instance, when it comes to the efficiency of the different solar panel types, monocrystalline solar panels have the highest efficiency. Polycrystalline solar panels, on the other hand, have a slightly lower efficiency rate.
Module Efficiency vs. System Efficiency
When converting sunlight into electricity, not only solar panel efficiency should be taken into consideration. In the solar energy system, in addition to the panel, there are also equipment such as inverters and cables. These equipment have their own efficiency.
Solar power systems also rely on inverters to convert the direct current (DC) from PV cells into the alternating current (AC) needed to power your home appliances. The best solar inverters are more than 97% efficient, but you can still expect minor losses during transmission.
Considering the total system efficiency, it is below the solar panel efficiency. For example, the total efficiency of a system with a 20% efficient panel will be around 17% – 18%.
How to Increase Solar Panel Efficiency
In order for solar panel efficiency to be constantly high, installation should be done by a professional team. To increase solar panel efficiency, you must first perform or have your system maintained regularly. The efficiency of poorly maintained systems decreases very rapidly.
Let’s examine the things to be done during the maintenance phase under headings.
Professional Installation
Professional and correct installation is very important for the life and efficiency of your solar power plant. Manufacturers give a lifespan of 25-30 years for solar panels and state that panel efficiency will decrease by around 10% during this period. In order to prevent your efficiency from decreasing further, engineering work must be carried out correctly during installation.
Also, the warranty coverage is well researched. Faulty panels or inverters can be replaced free of charge under warranty.
Clean the Solar Panel
Solar panels convert the sunlight falling on them into electricity. If the panel surfaces are dirty (dust, bird droppings, etc.), less sunlight reaches the panels and the amount of electricity produced by the panel decreases. This means that your panel efficiency decreases.
Therefore, panel cleaning is of great importance for efficiency. However, the following conditions should be taken into consideration when cleaning or having it done.
- You should stay away from hard brushes or abrasive chemicals during cleaning. Cracking or scratching panels will reduce efficiency.
- If possible, use brushes produced for panel cleaning. If not possible, choose soft brushes.
- One solution is to wash your panels with a hose. However, washing the panels with a hose while they are hot may cause cracks. This is a factor that reduces your productivity.
Remove Shadows
Shadows directly affect your panel efficiency. If you have a solar power plant on the land, trees or overgrowing grass will cast shadows on the panels and reduce efficiency.
Since the sun does not remain constant and moves during the day, sun angles change and shading also changes. If necessary, shadows that may occur should be detected and eliminated in advance by real-time simulation.
