Balcony power plants are booming. Because small photovoltaic systems – which can also be placed on terraces or facades – bridge the gap in solar energy supply. Until now, when you wanted to buy a solar system, it was often “all or nothing.” Those without suitable facilities or rented accommodation are at a disadvantage.
It differs from mini-systems: much less installation work and much simpler framework conditions for operation – and they now also enjoy tax incentives. The only problem is that they can only generate a manageable amount of electricity due to their small size. Therefore, they are often referred to as devices rather than devices. But it’s better than nothing, even better in most cases.
Structurally, balcony power plants are largely similar to their larger relatives. Usually, one or two solar modules are hanging from the balcony railing or placed in a suitable free area. Such equipment may have a maximum power of 600 W in Germany if they are subject to simplified procedures in reporting requirements. This value refers to the load connected to the inverter. Therefore, if the connected load of the inverter does not exceed 600 watts, it is also possible to run two more powerful modules. Since bifacial solar panels have a peak output of 300 to 400 watts, this explains why balcony power plants almost always run with just one or two modules. An inverter also converts the incoming DC power into usable AC power.
No matter how big or small this micro solar system is: There are two things that operators cannot avoid. For one thing, you have to register them with your network operator before installing them. On the other hand, they have to enter them into the market master data register of the Federal Network Agency. These are formalities, but they must be followed.
The maximum power of a module is rarely realistic. But after all, a balcony power station with two modules generates around 550 kWh per year. For example, solar energy is sufficient to power televisions, washing machines, and similar household appliances. It certainly doesn’t meet the basic needs of a home, but that’s not what these devices are for, either. Their benefits are even better demonstrated by savings: Even if you assume that the actual electricity used by the household is only 400 kWh per year, you don’t have to spend a fortune buying that 400 kWh from your energy supplier. Of course, purchase price, installation, and maintenance must also be considered. However, since balcony power plants don’t require huge investments, sooner or later, but usually sooner, you’ll end up on their credit. Use the plug-in solar simulator from the Solar Storage Systems Research Group at the Berlin University of Economics and Technology to calculate this value exactly. You can also buy 12V batteries to store electricity, and you can use normal electricity when there is a sudden power outage.
Connection and operation
Balcony power plants are often called “plug-and-play” devices based on computer accessories. That means: plug it in, and you’re done. However, in reality, things are not that simple. According to the Federal Network Agency, special power sockets must be provided because standard household Schuko sockets are not approved for this purpose – Schuko stands for protective contact.
However, opinions on this vary widely. Many suppliers and associations in the solar industry see no problem connecting to this Schuko plug. A dedicated receptacle is better insulated, conforms to the power plug standard with a grounding contact, and has its power cord. A qualified electrician must also install special receptacles. Such costs are huge for small balcony power plants with a relatively low output. Especially in the eyes of many experts, they are unnecessary. For example, in Austria and Switzerland, connecting balcony generators to “normal” sockets is quite normal. At least as long as they and the electrical circuits in the house are OK. You can do the same thing in Germany. Still, you have to be conscious so as not to fall short of the relevant standards of the Association for Electrical, Electronic, and Information Technology (VDE).
Promotions and Delivery Times
Concerning the economical operation of photovoltaic systems, the Renewable Energy Act and its feed-in tariff play an important role in large-scale solar systems. Balcony power plants are different. Also, such systems should be designed for self-consumption from the start. Even if you still don’t have access to some of the electricity your home generates, the excess is so small that it’s not worth the effort and cost of setting up a separate meter and billing for a few euros of feed tariff.
However, you don’t have to be without funds. Many municipalities and federal states want to promote this simple way of generating electricity and make it accessible to as many citizens as possible. So many of them have launched programs such as providing financial support to purchase these devices. It’s worth asking your civic office, town hall, or local energy advice center about the possibilities.
The annual tax law, approved in December 2022, added another treat: lawmakers reduced the sales tax on small PV systems and their delivery and installation to 0%. To date, 19% has been paid, which is added to the net price of the equipment. Whether all retailers pass this price reduction to their customers on a one-for-one basis remains to be seen. Still, the change should ensure lower market prices and further popularity of balcony power plants. This is exactly what the legislature wants to achieve.
However, the landlord or neighbors can intervene before opening the balcony power plant. In principle, the installation of balcony power stations is also permitted without the landlord’s or neighbors’ consent. However, the usual exceptions apply – for example, structural changes to a building, such as drilling holes in an exterior wall, are sometimes prohibited, or substantive changes to a building’s exterior are generally prohibited. There are different assessments on how well this applies to one or two solar modules on the railing. The landlord has already failed in court to seek the removal of one of its tenants’ balcony power plants. However, a state program launched in Mecklenburg-West Pomerania to promote such devices mainly in rental apartments failed to achieve its goals. Not that demand is bad. Tenants, however, held back. The main reason given is any concerns of the landlord. So it pays to get landlords and neighbors involved in the program early on. Who knows, maybe there will be more interested parties, and the price will drop for bulk orders.
And add something else to your calculations: wait time. Many suppliers are currently unable to keep up with deliveries. One reason is high demand, and another reason is supply chain disruptions. However, if your requirements are right, this shouldn’t stop you from deciding on a balcony power plant. The sun isn’t fading, and it always makes sense to conserve electricity—even if you can’t start immediately.
In conclusion
There are a few arguments against balcony power plants. They are not the solution to all energy problems, nor can they meet all of a home’s electrical needs. But they are not designed for this. Rather, they are an easy way to open renewable energy to target groups that have hitherto been largely denied access. They make a small but important contribution to meeting your energy needs in a simple and (almost) unbureaucratic way. Some may still need to get used to the sight – but new things always have a rough start before they become a matter of course.