Solar energy is an inexhaustible resource, one of the cleanest sources of energy and therefore environmentally friendly. On our planet, we have an enormous amount of solar energy obtained from the sun. We can put this solar energy to good use.

 Photovoltaics - what it is and how it works

the sun shining on the roofs of housesThe word ''photovoltaics'' comes from the English word ''photovoltaics'' which means: ''photo'' - light and ''volt'' - unit of voltage measurement. A common abbreviation is PV.

Photovoltaics, therefore, is the field of science that deals with the conversion of sunlight into electricity. That is, the generation of electricity from the sun's rays. This is made possible by the use of various technologies, primarily photovoltaics. This conversion of light into electricity takes place in so-called photovoltaic cells. This is an environmentally friendly source of renewable energy.

Photovoltaic cells are manufactured from a semiconductor material (it is usually silicon) and by joining together they form a photovoltaic module. This module is housed in an aluminium or steel frame to protect the cells from mechanical damage. In these cells, the photovoltaic phenomenon takes place - the conversion of energy from the sun into direct current. This current then runs to a device called an inverter (inverter). Here, the direct current is converted into alternating current (i.e. the kind we have in our household sockets).

The photovoltaic installation includes:

  • Photovoltaic panels (called solar) - convert energy from the sun into electricity

They can be monocrystalline or polycrystalline. They differ in colour, structure and efficiency. Monocrystalline panels have a black colour, while polycrystalline panels are blue. Monocrystalline have a higher efficiency and power output than polycrystalline.

There are also CIGS cell panels (good for building facades) and CdTe cell panels (have a distinctive red colour and are made of a single cell).

  • Inverter - converts direct current into alternating current

It is known as the heart of the installation. It regulates the operation of the PV system. Its task is also to provide protection during a fault, during a power failure in the grid. In this case, it disconnects the PV system and interrupts energy distribution. The inverter can be mounted externally or internally. There are 3 types of inverters: central inverters, micro inverters and string inverters.

  • Mounting system - allows panels to be mounted on a variety of roof types and surfaces

It is most often made of stainless steel and/or aluminium, due to the fact that these materials are rust-resistant.

  • Wiring - cables connecting installations to the internal network

Specialised accessories are needed to connect everything together. These include AC/DC protection, junction boxes, MC4 connectors and splitters. This cabling should be resistant to harsh weather conditions and UV rays.

Like every thing, a photovoltaic installation also has advantages and disadvantages. The advantages of a photovoltaic installation are:

  • Possibility of selling excess stored energy
  • Total access to solar energy
  • Independence from electricity price increases
  • With continuous power generation, zero carbon emissions
  • Guaranteed for 25 or even 40 years

As for the disadvantages of a photovoltaic installation, the main one is its initial cost.

Before starting the installation, it is very important to fit and check the individual components. It is necessary to analyse, for example:

  • possibility to position the panels (e.g. on the roof or ground)
  • roof layout
  • type and number of photovoltaic modules
  • inverter selection
  • the times of energy use

Photovoltaic installer - what he does and his qualifications

roof fitter for photovoltaic panels".The work in photovoltaics is to adapt a residential, public or commercial building to take solar energy and convert it into electricity. On the technical side, this involves installing the panels, connecting them to an inverter and connecting everything to the electrical system.

Installing a photovoltaic system may seem like a simple task at first glance, but in reality it is not. There is a lot of voltage and power being generated, so an incorrect installation may cause a fire, short circuit or other hazard. For this reason, the person responsible for the installation (photovoltaic fitter) must be qualified.

The photovoltaic installer is a relatively new profession on the market and not yet fully known to everyone. So what does his job entail? His duties include:

  • Installation of photovoltaic systems
  • Inverter configuration
  • Electrical work
  • Assembly of inverters together with protection on AS and CD side
  • Earthing and electrical measurements
  • Installation of cable routes for the photovoltaic system
  • Customer care
  • Installation of ground and roof structures - related work

What qualifications should a photovoltaic installer have? A person who undertakes work in this industry should hold at least one of these qualifications:

  • SEP authorisations (Association of Polish Electricians). A person who carries out electrical work should have one. This qualification certificate, which entitles you to deal with the operation of equipment, networks and installations, must be valid.
  • Possession of a certificate which confirms the qualification to install renewable energy sources. This certificate is issued by the Office of Technical Inspection (UDT). The certificate is issued for 5 years. In order to obtain it, the holder must undergo training at a centre designated for this purpose and pass a state examination before a UDT commission.
  • be qualified to work at height. The fitter should have this qualification as the installation of the panels sometimes requires working on the roof, in which case he/she must observe personal protection and health and safety regulations.

With more and more solar panel installations, the job of a fitter seems to be a secure income. Besides, it is possible to find employment in other European countries.

The tremendous technological development in the world in recent years, together with the development of our ecological awareness, has made photovoltaics one of the fastest growing industries in the industry today. The largest photovoltaic markets in the world are China and the United States. In Europe, the Netherlands and Germany lead the way, followed by Spain. According to forecasts by Social Power Europe, global photovoltaic capacity will increase by 225 GW in 2023.

In Poland, photovoltaics are also becoming more common. The installed capacity of photovoltaics in February 2021 was 4244.03 MW, and this year it is more than double that. The number of new PV installations is more than 45,000 units.