Photovoltaics is considered one of the most environmentally friendly sources of electricity. Unlike many other power generation technologies, photovoltaics do not emit harmful substances into the air or water, which means it is clean and environmentally friendly. What is the life cycle of photovoltaic panels?
Production of photovoltaic panels
Opponents of photovoltaic installations often raise the issue of panel production and its bad impact on the environment. Let’s check how it looks in reality.
Photovoltaic panels are built from fossil raw materials. The basic raw material we need for production is quartz, mined from open-pit mines, but it can also be obtained from beaches or inland dunes. Mining it can have a negative impact on soil quality and water pollution or loss of natural resources. Subsequent production processes consume large amounts of energy to produce polycrystalline silicon.
Large amounts of water are used in the production of photovoltaic panels. It is used not only in production processes, but also for cooling and washing equipment.
Production processes can emit harmful substances into the environment, such as carbon dioxide, the excess of which in the atmosphere is a major cause of climate change. Also nitrogen oxides or various types of dust. Emissions of these harmful substances result from the use of raw materials such as silicon and metals in production. Below is a chart that illustrates the amount of carbon dioxide emitted by various heat sources during their life cycle.
We can see that photovoltaics, despite producing carbon dioxide, cannot match the amounts produced by conventional energy sources.
Operating time and energy production from the sun
Photovoltaics does not need fossil fuels to produce electricity. It gets its energy from solar radiation. When the smallest unit of light – a photon – falls on a silicon wafer, it knocks an electron out of the valence shell. These freed electrons are the flow of direct current, which is directed to the inverter, whose most important task in the installation is to convert direct current into alternating current. We can install photovoltaic panels both on the roofs of buildings and on the ground, and even on the walls of buildings.
Photovoltaic panels last a minimum of 25 years with a high efficiency of over 80%. The higher the quality of the modules, the higher the efficiency after years of operation. After 25 years of operation, the efficiency decreases, but this does not mean that the modules become useless. They still produce large amounts of electricity and can be used safely.
What’s next Recycling or landfill?
Photovoltaics in Poland have only become popular and used on an increasing scale in the last dozen years or so. This means that the problem of used photovoltaic panels is yet to come. Fortunately, photovoltaic panels can be recycled! We wrote an entire article on this topic, which you can find here: https://evolive.pl/instalacje-fotowoltaiczne/utylizacja-paneli-fotowoltaicznych/
When the need to recycle panels on a large scale arises there will be companies that will start offering such services. Of course, we cannot promise that all panels will be recycled. This depends primarily on the awareness and goodwill of the owners of photovoltaic installations.
Is photovoltaics ECO?
It is difficult to estimate how much water is used in the production process of photovoltaic panels, it depends on many factors. It is also difficult to estimate the scale of environmental degradation in the extraction of raw materials needed for production. However, the more than 30-year working life of the modules, during which the installation generates virtually no additional costs (servicing and repairs in a properly designed installation are rare), testifies to the positive impact on the environment. The use of any conventional energy source, in addition to the negative impact on the environment during the production of the source, releases harmful substances into the atmosphere during operation. Photovoltaic modules operate emission-free, that is, from the moment they start working, they have no negative impact on the environment. The graph presented in Section 1 shows that the total emissions for the production of photovoltaic panels are about 50 g e/kWh, with traditional energy sources emitting into the atmosphere about 500 g CO2 e/kWh (gaseous fuels) or even approx. 1000 g e/kWh (coal fuels).
The recyclability of photovoltaic panels means that they will not leave a long-term footprint on the planet. Top-down regulations would help in this regard, which would mandate that used parts of the installations be transferred to collection sites that would recycle them.