How many photovoltaic panels are needed for a home?

Most used photovoltaic kit For domestic use are those of 3, 5 yes 8 kW, So usually a house is used Between 7 and 20 photovoltaic panels of 410 W OR Between 7 and 18 photovoltaic panels of 450 W. Let's see what are the factors that influence the productivity of a photovoltaic panel and when you find the number of photovoltaic panels necessary for your home.

The cost of electricity is increasing and we are increasingly looking for ways to reduce consumption and electricity invoices. Photovoltaic panels are an increasingly popular solution that helps you reduce the value of energy invoices and contribute to the reduction of carbon dioxide emissions.

Factors that influence the need for photovoltaic panels for your home

To determine the need for photovoltaic panels for a home, it is necessary to consider the following aspects:

• The average consumption of energy, expressed in KWH, will help you understand the minimum power that the photovoltaic system will have to produce.
• The power supplied by a photovoltaic system is directly influenced by the average quantity of solar radiation in your area that falls daily on photovoltaic panels. Therefore, the second factor you need to consider is the average quantity of solar radiation. This varies according to the geographical position, orientation and the assembly angle of the panels and you can find it using a series of maps or computers (see more details below).
• The type and efficiency of photovoltaic panels:
  • Monochristalline panels They have the best efficiency, while polycrystalline and amorphous panels have less efficiency, but they are cheaper,
  • Half -cell technological panels It offers better performance in partial shading conditions compared to full cell panels.
• The most recent and effective photovoltaic panels, available from half -2023 are N-Type photovoltaic panelswith an efficiency of over 22%.

As I said, the amount of energy produced by a photovoltaic system depends on the amount of sun radiation received from the photovoltaic panels and this differs according to the position, orientation and the corner of mounting the panels.

Above, the Solar Radiation maps of Romania are presented for photovoltaic panels mounted horizontally and for the photovoltaic panels mounted on the optimal corner. The maps are calculated for 1 kWpeak photovoltaic systems with a performance ratio of 0.75 kWh/kWpeak. From the two maps you can see that the sun radiation received from a photovoltaic panel mounted on the optimal corner is greater than the sun radiation received from a horizontal photovoltaic panel. That's why you have to take a lot of care of the corner of mounting the panels.

How is the need for photovoltaic panels for your home?

Step 1: Calculate the necessary electricity requirement expressed in KWH. To do this, check the energy bills of the last year, determine what the monthly environment or the average daily consumption is and take into account the consumption peaks in December and January.

Step 2: Calculate the production of effective energy provided by a photovoltaic panel using a computer such as the one provided by the EU. In this calculation it is necessary to take into account the type of panel and photovoltaic system (Su-Grid or Off-Grid), geographical position, panel orientation, corner and location in which the panels are mounted.

Step 3: Divide the average consumption of energy to the production of effective energy provided by a panel mounted according to your conditions. You will get the number of photovoltaic panels necessary to cover the average monthly consumption.

To cover energy needs on winter days or cloudy days we recommend mounting a greater number of photovoltaic panels than that resulting from these calculations. If the budget does not allow you to integrate the number of panels from the beginning, you can do it later.

The most used kits of photovoltaic panels for the home

Depending on the consumption of energy and geographical position, the most used kits of photovoltaic panels are 3, 5, 8 or 10 kW.

A system of photovoltaic panels offers a different electricity production depending on the type of panels (polycrystallines, monochristallines, amorphous), the orientation of the panels (south, west), the corner in which they are mounted and the position in which they are mounted.

Kits Potovoltaic Panels 3 KW – Energy production depending on the location

For example, for a 3 kW photovoltaic panels mounted in a house in Constanta, using the above computer you get the following results: the following results:

• The optimal orientation is south;
• The optimal assembly angle of the photovoltaic panels in Costanta is 35^or;
• The total annual energy production is 3.67 kWh and monthly production varies between 156 kWh in winter and 455 kWh in summer. The production of monthly energy varies according to the number of sunny days of that month.

For the same system on the grille of 3 kW photovoltaic panels mounted in Brasov, get the following results:

• The optimal orientation is in the south;
• The optimal corner for the assembly of the solar panels in Brasov is 36^or;
• The annual production of a 3 kW photovoltaic panels kit is 3,266 kWh, with a monthly energy production ranging from 136 kWh in winter and 386 kWh in summer.

In our article How much electricity produces a 5 kW photovoltaic system In a month you can find out how the production of monthly energy of a 5 kW photovoltaic kit varies during the year and according to the city in which it is mounted.

What contains a system of photovoltaic panels?

A photovoltaic system consists of a series of equipment, which differs depending on the type of system desired: Su-Grid, Off-Bridal or Hybrid. The components of a system of photovoltaic panels are as follows:

• The photovoltaic panels, chosen according to the necessary power, the position in which the available budget is mounted;
• The fixing system of the photovoltaic panels differs depending on the place of assembly of the panels, on the ground or on the roof. For photovoltaic solar panels mounted on the roof, the assembly system differs according to the type of roof: tiles, corrugated sheet etc.;
• Solar inverter (single-phase or three-phase inverter), chosen based on the type of photovoltaic system you want: Su-Grid, Off-Grid or Hybrid;
• Cables and solar connectors: pay attention to the thickness and length of the sunscreen, the more the cables are the losses. In most cases, inverters also include connection cables;
• Solar batteries for energy storage, in the case of hybrid or off-grid photovoltaic systems;
• Monitoring and control systems of electricity production
• If you opt for Prosumes, the electricity distribution company with which you have signed the Prosumor contract will change your electric meter with two ways.

For more information, please read the article too What contains a system of photovoltaic panels

5 steps to create the best photovoltaic system for the home

To choose the best system of photovoltaic panels for the house, it complies with the following steps:

Step 1 – correctly determines the electricity requirement starting from the energy invoices of the last year or taking into account existing consumers.

Passage 2 – Choose the model of the desired photovoltaic panels. We advise you to choose high performance photovoltic systems and which degrade a little over time. Therefore, we advise you to choose the photovoltaic panels of consecrated producers (level 1), which will give you the certainty that they are able to provide your guarantee for 10 years.

Step 3 – establishes the number of photovoltaic panels necessary depending on the type, position and orientation. Check if the surface you want to mount is large enough to allow the installation of all panels.

Step 4 – Determine the type of inverter based on the type of desired photovoltaic system:

• On the photovoltaic system on -Grid – provide the surplus of energy in the network and consume the network when energy production is not enough. You need an inverter on the grid and a BigEctional counter that the electricity distribution company will install.
• Off-Grid photovoltaic system: the system is not connected to the national network and the energy surplus is stored in the batteries, it requires an off-grid inverter.
• Hybrid photovoltaic system – is a mixed system that contains both the battery for the conservation of electricity and for the hybrid inverter.

Check if the chosen inverter is compatible with photovoltaic and accumulators panels.

Passage 5 -the necessary installation kit according to the place of installation, on the ground or on the roof and according to the type of roof.

It is possible to determine the effective quantity of energy produced by a panel or a photovoltaic system by accessing the computer provided by the European Union. Here it is possible to calculate the production of monthly energy depending on the type of photovoltaic panels, the power of the photovoltaic system, the losses in the system, the orientation of the panel (azimut), the corner in which the panels, the position and the type of photovoltaic system (on-grid, off-grid, hybrid) are mounted.

Passage 6 -Secellular and compare several offers of photovoltaic panels kit, check the components of the photovoltaic system included in each offer, the guarantee and assembly conditions.

Step 7 -Coose the winning offer, follow the correct assembly of the photovoltaic panels and enjoy the energy saving.

Recommended brands of photovoltaic panels for the home

For a photovoltaic system with high efficiency and a high warranty term we recommend that you choose the last generation solar panels, of type N, from consecrated producers. These types of solar panels can reach an efficiency of over 22%, have a guarantee of up to 15 years. In addition, the photovoltaic solar panels of the best brands maintain over 84% of the initial production capacity, even 30 years from the production date.

Choose the manufacturers of photovoltaic panels evaluated 1. They are very financially stable, they have a high ability to invest in technological innovation and you are able to provide your guarantee for 10 years.

On our site you can find manufacturers of photovoltaic panels classified for level 1 such as QCEL, Jinko Solar, Longi or Canadian Solar.

Authorized AFM installers for the assembly of photovoltaic panels

Even if you can mount the photovoltaic panel system, we recommend that you resort to an authorized installer so as not to lose the guarantee and avoid the danger of a fire.

In the event that you want to request funding through the Casa Verde program, the installation must be carried out with a company authorized by the administration of the Environment Fund. The list of installers validated by AFM within the program during the installation of photovoltaic systems is available on the AFM website.

If you have further questions about this article or if you want to discover more information on photovoltaic systems, we invite you to contact us on the phone 0374.477.207 or email@zonetecsolar.ro.