As subsidies and aid to the solar energy, more people are choosing to install solar panels for their home. However, most buyers are not fully aware of the technical aspects and variables to consider when selecting a solar system. electrical self-consumptionLet's explore everything you need to know to make informed and correct decisions.
How much energy does your home need?
The starting point is to determine how much energy you consume annually in your home. This will allow you to estimate how much electricity you should generate using solar panels. In this section, it is important to consider aspects such as:
- Hours of sunshine available in your area: It is important to know how much average solar radiation your home receives throughout the year. The number of hours of sun varies depending on the geographic location and the inclination of the roof.
- Energy consumption: Take a detailed look at your electricity consumption. You can obtain this information by reviewing your electricity bills for the last 12 months.
- Consumption patterns: Identify the times of day when you consume the most energy, which can influence decisions about storage and self-consumption.
With this information in mind, it will be easier to choose the amount and type of solar panels you need.
How to calculate the number of solar panels needed
To properly size your solar installation, you must first know the performance of the solar panels you plan to install. This is where factors such as panel efficiency, the characteristics of your roof, and possible shadows or obstacles that may affect direct solar radiation come into play.
- Types of solar panels: It is important to know the options on the market and compare their efficiencies. Monocrystalline panels, for example, have a higher efficiency than polycrystalline ones and, although they are more expensive, they take up less space to produce the same energy.
- Solar panel power: The nominal power of a solar panel is measured in peak watts (Wp). It is important to compare the generating capacity of a panel when it is receiving direct solar radiation.
Seeking advice from manufacturers and experts is crucial to understanding not only how many panels you need, but also where to place them to maximise performance. Plus, you can choose between roof-mounted panels, ground-mounted panels, and tilted or mobile systems, depending on your needs.
Different types of solar panels
In the market there are different types of solar, the most common are:
- Monocrystalline: Made from high-purity silicon, these panels have higher efficiency (17%-23%) and performance, but are usually more expensive.
- Polycrystalline: They are a little less efficient (15%-17%) than monocrystalline, but they are also cheaper and can be an ideal option if you have enough space.
- Amorphous or thin film panels: Although they are less efficient (range 10%-12%), their flexibility and low cost make them useful in specific circumstances.
Beyond the traditional types, in recent years innovative technologies applied to solar panels have emerged:
- Half-Cut Panels: They have half cells, which allows them to reduce electrical resistance losses and increase efficiency, especially when part of the panel is shaded.
- Bifacial panels: These panels are capable of capturing solar radiation on both sides, which increases energy production.
- PERC panels: They include an additional layer that reflects part of the unabsorbed light to increase efficiency.
Installing Solar Panels: Key Considerations
Before you make a purchase, in addition to the quality and quantity of solar panels, consider the costs associated with installation and the additional equipment you will need:
- Installation cost: Don't forget to include in your calculations the cost of professional installation, which can vary depending on the type of roof and the difficulty of accessing it.
- Solar inverter: It converts the energy generated into alternating current, which is what most household appliances use.
- Storage systems: This option is useful when you want to store excess energy generated during daylight hours for later consumption.
The ideal installation should take into account:
- Orientation: Panels should face south (in the northern hemisphere) to capture the most sunlight.
- Inclination: The optimal angle for your installation will depend on the latitude of your location, although an angle close to 30 degrees is generally recommended.
- Shadow: Evaluate whether there are objects that may cast shadows, such as nearby trees or buildings, that may affect performance.
Warranties and maintenance of solar panels
when acquiring solar, you should not overlook the warranties offered by the manufacturer. There are two types of warranties to consider:
- Product Warranty: It usually covers manufacturing defects, and is generally offered for 10-15 years, although some manufacturers offer up to 25 years.
- Performance Guarantee: It refers to the loss of efficiency of the panel over time. Most manufacturers guarantee that after 25 years the panel will maintain at least 80% of its initial efficiency.
As far as maintenance goes, the good news is that the solar They require minimal maintenance. It is recommended to clean the surface of the panels every 6 months or when obstructions are detected that may reduce light absorption. In addition, the electrical systems should be checked annually.
Grants and subsidies for the installation of solar energy
The decision to install solar panels has become more feasible due to the grants and subsidies available in many countries. In Spain, there are several State and regional subsidies which can significantly reduce the installation cost:
- Recovery, Transformation and Resilience Plan: Aid for the installation of renewable energies such as solar.
- IBI and ICIO bonuses: Some local governments offer discounts on the Real Estate Tax (IBI) and the Tax on Construction, Installations and Works (ICIO) for those who install solar energy.
- Personal income tax deductions: In certain autonomous communities, percentages of the installation cost can be deducted from the income tax return.
Taking advantage of these grants can reduce the total cost of the installation by up to 40%, so it is advisable to find out which ones are available in your area and how to apply for them.
There is no doubt that investing in solar energy is a strategic decision for the future, not only because of the savings on the electricity bill, but also because of the environmental benefits, energy independence and the possibility of contributing to a healthier planet for future generations.