Useful Information about PV Systems

A photovoltaic system (PV system) directly converts sunlight into electrical energy by utilizing the photoelectric effect. These systems consist of solar panels, which are made up of many solar cells, typically made of silicon. When sunlight hits the solar cells, the light particles (photons) are absorbed by the silicon atoms. This causes electrons in the solar cells to be excited and released, creating an electric voltage.

This voltage drives electrons through a circuit and generates direct current (DC). Since most household appliances and the power grid operate on alternating current (AC), the DC is converted into AC by an inverter. The AC produced can either be used directly in the home or fed into the public power grid. Excess power can also be stored in battery storage for later use.

Many PV systems are connected to the grid, allowing excess electricity to be fed into the public grid and drawing power from the grid when needed. This makes the use of solar energy flexible and efficient.

A PV system is worthwhile in regions with high solar radiation, as the efficiency and amount of energy produced are highest there. It is particularly beneficial when electricity prices are high, as self-generated electricity is cheaper than purchasing from the grid. Environmental aspects also play an important role, as PV systems provide clean and renewable energy while reducing CO₂ emissions. If suitable roof spaces or open areas are available and installation costs can be reduced through government subsidies or favorable financing options, a PV system is also a worthwhile investment. Additionally, it increases independence from the power grid and protects against future electricity price increases.

Yes, a PV system must be registered. Before commissioning, it is required to register with the local grid operator, who checks whether the grid can handle the additional power feed. After installation, the system must be registered with the Market Master Data Register of the Federal Network Agency. Additionally, registration with the tax office may be necessary, as PV system operators may be considered entrepreneurs and have corresponding tax obligations. These steps are important to comply with legal requirements and to benefit from potential subsidies and compensations.

A balcony power plant, like any other power generation system, must be registered in the Market Master Data Register of the Federal Network Agency. Since May 16, 2024, with the implementation of the Solar Package, registration with the grid operator for plug-and-play solar systems, also known as “balcony power plants,” is no longer required as long as they do not exceed the usual performance values (gross output of 2,000 W and associated inverter capacity of 800 W). By registering in the Market Master Data Register, the grid connection operator is automatically informed about the system operator’s and system’s data.

Solar roof tiles are an interesting option for integrating solar energy into roof architecture. Their usefulness depends on several factors:

Solar roof tiles are an aesthetically pleasing solution, as they look like traditional roof tiles and are therefore less noticeable than conventional solar panels. This makes them particularly attractive for those who do not want their home’s appearance to be affected by separate solar panels. They can be especially worthwhile if the roof needs to be replaced anyway, as the installation of solar roof tiles is often simpler in such cases.

However, solar roof tiles are typically more expensive than conventional solar modules. They also tend to have lower performance per square meter compared to standard PV modules, as they have poorer ventilation and thermal stress, which leads to lower efficiency. This means that larger areas are needed to generate the same amount of energy. Additionally, installation may be more complicated due to specific requirements and higher costs.

Overall, solar roof tiles are useful when aesthetic considerations and integration into the roof structure are a priority, and the higher costs and potentially lower efficiency are acceptable. If the main priority is maximum energy yield, traditional solar panels may be the better choice.

Renting or leasing a PV system can be a sensible alternative to purchasing, especially if the initial investment costs for acquiring one are too high or if you want to avoid the long-term responsibility for maintenance and operation.

When renting or leasing a PV system, the initial costs are generally lower since you don’t have to bear the entire investment cost. Instead, you pay regular rental or lease payments, which are often fixed and thus offer planning security. The maintenance and upkeep of the system are typically handled by the operators of the PV system, reducing the effort for the renter or lessee.

Another advantage is flexibility. If personal or financial circumstances change or if you move, the rental or lease model can provide a simple solution without having to worry about disposing of or selling the system.

However, the long-term cost-benefit ratio of renting or leasing may be less favorable than purchasing, as over the years, the total costs might end up being higher. Additionally, renting or leasing offers less control over the technology and operation of the system.

Overall, renting or leasing a PV system can be a viable option if you don’t want to bear the full investment cost or prefer a flexible solution. However, it is important to weigh the long-term costs and benefits and carefully compare the offers.