How solar panels work using the sun’s energy is easy to explain. When sunlight hits a solar cell, its electrons move and generate direct current. This is converted to an alternating current in an inverter. With solar thermal panels, the sun’s rays heat the liquid in the panels, which is then emitted as heat.
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How Solar Panels Generate Electricity
The solar cells in a solar module are solely responsible for generating electricity, including the required “solar panel repairs.” When the sun’s rays fall on the photovoltaic panel, the photons of the sunlight move the solar cell’s electrons, contributing to the energy production. They pass through the wiring in the form of a direct current, which is then fed into an inverter. This crucial component converts the direct current into usable alternating current. Once converted, the electricity flows from the inverter to the meter for consumption within the household grid, or it can be fed into the public grid.
Hot water function solar panel
Solar collectors work similarly. However, instead of solar cells, they have tubes filled with a special water-glycol mixture. When the sun’s rays hit the tube, the liquid heats up due to infrared radiation. The warm liquid is then drained into a storage tank, and a heat exchanger is used to heat the water. It then flows back to the bifacial solar panels, now cooling down again. A water storage tank keeps the water warm for hours and is distributed throughout the house by a pump. Unfortunately, unlike photovoltaics, unused energy cannot be fed into the grid.
How much do solar panels cost?
The average cost of a solar panel is between 150 and 200 Euros. The price depends on the performance and quality of the modules. Solar thermal panels have a wider price range, ranging from €375 to €750 per square meter. Both already include shipping costs.
Cost of generating electricity from solar panels
Solar panels cost between €120 and €340 for a conventional 300-watt solar panel. The exact price depends on various factors, such as the type of solar cell and its performance. When comparing prices, costs are usually expressed in euros per kilowatt-peak (kWp) or cents per watt-peak (Wp), not per panel. Depending on the manufacturer, prices can vary widely.
Monocrystalline solar panels cost more than thin-film solar panels but produce almost twice as much solar energy. Therefore, you need more thin-film modules to generate the same amount of electricity.
The cost of hot water solar panels
They use solar panels for hot water costs between 375 and 750 euros per square meter. An area of five square meters can already cover the hot water consumption of a family. The total acquisition cost of the system is between EUR 4,000 and EUR 6,000. Solar panels cost less than €1,000 to €2,500.
If you also want to use heat for heating, you need at least twice the number of solar panels—the total cost of a solar thermal system averages between 8,000 and 10,000 Euros.
Solar panel manufacturer
Germany has a large number of manufacturers of both solar panels for photovoltaic systems and solar collectors for solar thermal systems.
In our large solar panel test, we tested and compared the most famous and largest solar manufacturers for you.
| Manufacturer | Country |
| Luxor | Germany |
| REC | Norway |
| Hanwha Q Cells | Germany |
| SunPower | USA |
| Renogy | USA |
| Astro Energy | China |
| Suntech Power | China |
| BYD | China |
| Canadian Solar | China |
| Meyer Burger | Germany |
| Canadian Solar | China |
| Meyer Burger | Germany |
| Bauer | Solar Germany |
| Trina | Solar China |
| Seraphim | China |
| Joywood | China |
| Hyundai Energy | South Korea |
| LONGi | China |
| Viessman | Germany |
| Solarwatt | Germany |
| ZNShine | China |
| Winaico | Taiwan |
| Yes Solar | China |
How big are the solar panels?
Solar panel sizes vary by performance and use. Typically, photovoltaic systems have solar panels with an area of 1.6 to 2 square meters each. Typically 60 individual solar cells measuring 156 mm x 156 mm are installed.
The size of solar panels for solar thermal also depends on performance, manufacturer, type, and use. Thus, the average area of solar collectors on private roofs is 2 to 2.6 m².
How many solar panels do I need?
How much solar do I need depends on your use, an average family of four needs about 4,500 kWh of electricity annually. Photovoltaic systems in Germany generate approximately 1,000 kWh of electricity per kWh of photovoltaic output. A 5 kW photovoltaic system is therefore required. Conventional solar panels have an output of 260 to 340 Wp, so 16 to 20 solar panels are required.
You can install a power storage unit to suit your needs even in winter or on days with less solar radiation, such as cloudy days. A power storage system can absorb excess green power and release it again when needed.
How long do solar panels last?
If the solar panel is made of crystalline solar cells, it will reliably last about 30 to 40 years. Thin-film solar panels have a relatively short lifespan of 20 to 25 years. Solar panels for hot water should last at least 25 years. With good care and regular maintenance, 30 years or more is possible.
In conclusion
Solar panels convert solar energy into electricity or heat. There are two types of solar panels: photovoltaic panels, which convert sunlight directly into solar electricity, and solar thermal panels, which convert sunlight into heat. Choosing the right type of solar panel depends on your home’s unique needs and requirements.
No matter which solar panels you choose: Correct and professional installation is a basic requirement for properly functioning photovoltaic systems.
