Buy, set up and register a mini solar system

Energy prices are rising and after four mini solar systems have now been installed by families and friends, I want to summarize the most important points that you have to consider in order to legally operate a balcony power plant.

Mini solar systems have been around in Germany for a very long time. Previously operated as “guerrilla PV systems”, mostly secret, the legislator relaxed the rules considerably in 2019, so that basically only a few points have to be observed in order to be able to legally operate such a “balcony power plant”. With the With increasing energy prices, such a small PV system is very worthwhile. In addition, the first cities and regions are already promoting such systems.

Buy a balcony power plant

The interest in mini PV systems is constantly increasing, so that a problem is currently arising. Since February 2022, plug-in balcony power plants are no longer as easy and cheap to get as they used to be. At that time last year, a complete set with two solar modules, an inverter, cable and fastening material cost around 500 to 600 euros. Now you have to Lucky if you can get a set with everything for under 800 euros. The price is even tending towards 1,000 euros (check it out on eBay).

The problem is that that Interest is currently gigantic and the capacities for the production and delivery of solar panels and inverters from China are at their limit. While the inverters are only built for mini PV systems, the solar panels are also used in large PV systems for roofs. So there are several buyers here who really want these parts now.

Furthermore, there is a lack of accessories. Fastening materials for balcony power plants have also become scarce. For the last balcony power station that I built on the garden shed of my parents’ neighbors, we had to use a completely different bracket than my parents’. All this takes time because you then have to worry about stability again.

Use socket for feeding

In order to be able to operate a mini solar system via a normal Schuko socket, the inverter must have NA protection. This ensures that the entire system switches off immediately as soon as the frequency of the power grid is no longer detected. This is also the most important requirement that you have to meet with the network operator. Nothing works legally without it. But this is also an important protection for you.

Furthermore, the Inverters output a maximum of 600 watts. The solar panels can also have 2x 340 watts, for example, to get more out of less sun. In this case, however, a maximum of 600 watts can be output. In order to be able to measure the energy generated, you should use a WiFi socket with an app and energy measurement. I use those from AVM (look at Amazon). If you don’t have a Fritzbox, I can recommend this model for outdoor use (look at Amazon).

Alternatively, you can have a Wieland power socket fitted by an electrician. Then the system can also be stronger. But here additional costs arise, such special connections are usually not worthwhile. That’s why connecting to a Schuko socket should also be the option you choose. The requirements for this have also been relaxed.

Place the mini solar system in the right place

In order to be able to operate a solar system sensibly, you must of course have the right place for it. You can easily hang the mini solar system on a balcony railing. It’s important angle of about 30 degrees, to get the most out of it and ideally a southern exposure. If you own a house, fixing it is not a problem either. If you rent an apartment or a house, you have to get permission from the landlord.

But you can operate a mini PV system in many places. All you need is an outlet nearby. In my case, I simply installed the bracket myself on a carport.

Of course you have to a certain skill have to come up with a support so customized to the place. But you can find a lot of ideas on the internet that you can implement.

With my parents we simply used the garden shed:

What do you have to consider during assembly?

• Secure attachment: It is essential to ensure that the solar cells are installed securely and cannot come loose even in strong winds. A solar panel weighs around 17 kg and measures approx. 100 x 170 cm. If such a solar panel is caught by the wind, it can cause major damage or injury.
• Alignment: Where you want to install the solar system, you should observe the course of the sun throughout the day. South orientation is perfect, but small deviations are okay. Are there shadows from trees, buildings or other things? If something casts a shadow on the solar cells, the yield is noticeably worse.
• Inverter: You have to fix the inverter nearby. In my case it hangs on the back of a solar cell, with my parents we extended the cable into the garden shed. This protects it from the effects of the weather and should also work more efficiently without strong temperature fluctuations. Extension cables may also be required for installation in order to reach the inverter. The cables on the solar panels are usually relatively short.

Putting the individual components together is child’s play. You really can’t go wrong as each cable has a unique shape and can’t be misconnected. The two solar cells belong to the inverter and from there a cable runs to the socket. That’s it already.

Important: You should only operate a plug-in solar system on an electricity meter that has a backstop. If you still have an old meter, it must be replaced first. If the counter rolls back, you’re committing tax evasion and it can get really expensive if you get caught.

Register a mini PV system

For the legal operation of the plug-in balcony power plant, you have to register the system in two places:

• Network operator: You have to register your mini PV system with your grid operator. Many providers now provide simplified registration procedures, so you only have to fill out a form and enclose the certificate of the inverter. This proves that the inverter has NA protection. You only have one obligation to report to the grid operator, since he needs to know that you are feeding electricity into the grid as a generator. This is important so that the power grid is not disturbed. Furthermore, the network operator checks whether you have the right electricity meter and then replaces it if not. It doesn’t cost you anything.
• Market master data register: Furthermore, you must Enter the PV system in the market master data register. That’s easy too. There are a few pages to navigate here, but it’s pretty much self-explanatory. There’s also a lot of help on the website so it’s easy to find your way around. You are also required to report here. But you don’t need permission or activation. You fill out everything and the solar system can be used directly.

Don’t let the network operator unsettle you

That’s it already. You don’t have to do more to operate your balcony power plant legally. Everything used to be much more difficult because there was no simplified registration and the network operators made strange announcements. Everything is much easier now. While I was still fighting for three months to get approval for a new meter, it was at the two following plants after two to three weeks everything through – without discussions.

So don’t let the network operator talk you into anything. As long as the inverter has NA protection and does not exceed 600 watts, you can operate it on the Schuko socket. The VDE standard is thus fulfilled. A norm is not a law. This is often misunderstood. So don’t let that get you down. If you meet the requirements, then you are in the right.