Toronto Mike

The mini PV system in 2022

A few years ago, large solar systems gained attention. Nowadays, you can see them widely on the roofs of supermarkets, farms, industrial halls or in the open field. On the other hand, the mini PV system is a somewhat newer phenomenon. It is used for private use and the self-sufficient supply of the house electricity network with solar energy. In many ways, mini PV systems are very similar to conventional photovoltaic systems. Nevertheless, there are crucial differences.

Here you can find out when the purchase of a mini PV system is worthwhile for you and how you can easily install this photovoltaic system in your home.

What is a mini PV system?

The mini PV system is an abbreviation for a mini photovoltaic system. This smaller type of solar system, just like the larger ones, converts solar radiation into electrical energy. You can also use it to generate electricity yourself. However, mini PV systems are much smaller photovoltaic systems used exclusively to power private households. In contrast to the large systems, it is impossible to feed electricity into the public grid and receive financial compensation.

The mini PV systems are supplied as "plug-in photovoltaic systems". This means that they can be set up and used immediately after delivery. While large solar panels also have large inverters, mini PV systems have a micro-inverter. Both have the same function: They convert DC voltage from the solar modules into AC voltage so that the energy can be used as electricity in the home. Equipped with a micro-inverter, these smaller solar generators also enable private individuals to easily install them and connect them directly to the AC grid in their household.

Mounting options for mini solar systems

Mini solar systems can be easily installed in many places. These include facades, gardens, balconies and roofs. Because the construction and assembly are not very demanding, they can also be carried out by laypeople. Since the solar modules yield the maximum energy at an angle of approx. 30°, it is important to align the system optimally. This is achieved by the triangular elevation, which also ensures that the system is held securely. The riser and the screws should be tight and metal to withstand strong winds.

What distinguishes mini PV systems from other photovoltaic systems?

You should ask yourself whether you want to use a photovoltaic system for private or commercial use. Large solar panels installed in industrial halls or on large open-air meadows are mainly used for commercial purposes. Large solar panels can also be found on the roof or garage of a home, but this is only possible if owners have enough space. With larger solar panels, the energy generated can be fed into the grid and is financially rewarded via feed-in tariffs. In comparison, however, the small solar panels are only intended for private use.

Large solar panels are sometimes made from "thin film". A material that is very light and cheap to produce but only has an efficiency of 6% - 10%. In contrast, mini PV systems made exclusively from mono- or polycrystalline have much higher efficiency. Due to this nature, the smaller modules achieve an efficiency of 12% - 20%.

Now you may be wondering why the large solar panels are also not made from crystalline. In fact, this is often the case. However, because the modules are larger, crystalline ones weigh and cost much more than thin film ones. Although thin-film modules are not as efficient as crystalline mini-PV systems, they compensate for this with their size.

A mini PV system has an average size of around one to two square meters, and the output provided is around 100 to 600 W, depending on the condition and quality of the modules. The abbreviation W stands for "Watt Peak" and is used in photovoltaics Often used to indicate the maximum output of a photovoltaic system. With the specification of W, better comparability of different PV systems is possible. The output value for a mini PV system with 100 W is a power generation of 90-kilowatt hours of electricity per year. In contrast, large solar systems have 2,000 to 10,000 W and generate as much as 1,000 kWh per m² per year.

The construction of a mini PV system

In contrast to larger PV systems, a mini PV system is connected using a standard plug system. The micro-inverter forms the link between the plug and the PV system. Most inverters have both a display and an Ethernet connection. These two features help the user to call up the current and past yield data and the performance curve for the entire period via the display.

The solar module's connection to the house's main supply is ensured by a normal socket outlet with earthing contact. It is also possible to connect an electricity storage device (e.g. a classic solar battery) in which excess energy is stored for later use.

Another way of using the mini PV systems is the so-called off grid solar system. In this case, the solar system is not connected directly to the house's electricity network. Instead, the energy generated is temporarily stored in a solar battery. The advantage of the island system is that you can take the battery (such as 12v lithium battery or agm battery) with you and charge your laptop or other electronic devices outside the house.

Mini PV systems are also used on caravans and campers. Here they are used as stand-alone solar systems to ensure the power supply even in remote areas.

Because mini PV systems produce electricity exclusively for the household, the following is incredibly important: If the mini PV system transmits the electricity to the house via a plug and little or no electricity is consumed at the moment, the electricity is fed into the public grid. In this case, the electricity meter in your household runs backwards.

Modern digital counters are already equipped with a backstop. If you have an analogue meter without this blocking device, you should have it replaced before using the mini PV systems. You can easily request an exchange from your network operator.

Here you can read what you need to consider when buying an electricity meter.

For whom is the purchase of a mini PV system worthwhile?

The standard acquisition costs for a mini PV system are between 300 and 1,000 dollars. The yield, on the other hand, depends heavily on the geographical location within Germany and the exact location of the attachment. Most hours of sunshine in Germany are in the southern federal states and north-eastern Germany. Ideally, the mini solar system should be placed on a south-facing balcony to absorb the most solar energy. Otherwise, an orientation to the east or west is also useful.

In summary, the mini PV system is an inexpensive way to use solar energy for private households and to contribute to environmental protection. In addition, the maintenance of small solar modules is relatively low. In most cases, manufacturers grant a multi-year guarantee that covers the damage that usually occurs to solar systems. Furthermore, the assembly can be carried out quickly and easily without special knowledge. Depending on the electricity price and the installation location, a mini PV system pays for itself after an average of five to ten years.

Mini PV system - FAQ

Can you feed into the socket?

Unlike conventional systems, mini PV systems do not feed the electricity they generate into the public grid. Instead, they feed the electricity directly into the home network via a plug-in cable. This way, you feed the electricity from your mini PV system directly through the socket. While this is easily possible with conventional socket outlets with earthing contact, we recommend using special energy socket outlets. These are more robust and have a lower risk of overloading and overheating.

What is better, a mini PV system or a large PV system?

Mini PV systems are a very good way to generate electricity on the balcony, in rented apartments and caravans due to their price, easy installation and much lower regulations.

However, if you want to generate enough electricity to cover your total consumption, you should use large solar systems. Although these cost a little more, the return is far greater. In addition, the solar power generated covers your own needs and can be fed into the grid legally and without any problems. There is also a fee for this, which you cannot get with a mini PV system. If you have a solar system with solar power battery, you can even store the solar power and use it flexibly.

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