Solar power directly into the socket: too good to be true? c’t 3003 shows how easy it really is to install balcony power plants.
Electricity is becoming more expensive, consumption is high: a German household consumed an average of 2,828 kilowatt hours (kWh) from the grid in 2021. At current electricity prices, this amounts to four-digit costs per year. It seems all the more sensible to generate the electricity yourself from solar energy. With so-called “balcony power plants” you can do this on your own. But is it really that simple?
In the c’t 3003 video, the c’t editors Jan-Keno Janssen and Jan Mahn discuss the advantages of balcony power plants and show where possible stumbling blocks lurk in use. Because even if the technical structure is simple, some things have to be taken into account.
Landlords and network operators must be informed
For example, the landlord or landlady has a say in whether the balcony power plant is to be visibly attached to the outside of the balcony. In addition, the operation of a plug-in photovoltaic system, as it is officially called, must be reported to the grid operator. If a Ferraris meter is in use, it must be replaced by the network operator.
Some grid operators are also bothered by the Schuko plug that feeds the electricity from the solar panel into the grid – they speak of a danger for users. In fact, however, the NA protection prevents voltage from being applied when the plug is pulled. Despite the discussions, from a technical point of view there is nothing wrong with connecting a balcony power station to the grid with a Schuko plug.
Price savings from six years
In addition to the solar modules, the balcony power plant also includes an inverter that can be designed for a maximum of 600 watts in order to qualify for the simplified conditions. However, it is possible to overload the 600 watt inverter, for example by connecting it to two 400 watt panels, in order to still get as much energy as possible when there is less solar radiation.
For a solar module with 300 watts you have to plan around 250 euros, an inverter with 300 watts costs an additional 200 euros. Balcony power plants are sometimes available in complete packages at a reduced price. In addition to the costs for the balcony power plant itself, you have to factor in the expenses for the fastening material. A complete price for a system with 600 watts is around 700 euros.
The installation of a balcony power plant is therefore particularly worthwhile if you plan cleverly: If you let the washing machine run at 12 o’clock in the midday sun, you prevent excessive seepage of the overproduction into the power grid. A balcony power plant is therefore more suitable for home office workers, smart home fans and other frequent consumers than for people who only consume little. Under good conditions, a balcony power plant can save around 90 to 100 euros in electricity costs per year.
c’t 3003 is c’t’s YouTube channel. The videos on c’t 3003 are independent content and independent of the articles in c’t magazin. Editor Jan-Keno Janssen and video producers Johannes Börnsen and Şahin Erengil publish a video every week.
Did you know that you can just hang a solar panel on the balcony and just plug it into a regular outlet — and then you generate electricity? Without needing any additional electricity meters or contracts or anything? I didn’t know beforehand either. In this video I took a closer look at such a balcony power plant and peppered my colleague Jan with a lot of stupid questions about self-generation of electricity. Stay tuned.
Dear hackers, dear internet surfers, welcome to..
Electricity is getting expensive! Anyone who has to sign a new electricity contract today sometimes pays twice as much for a kilowatt hour as they did last year. We all know the reasons: We are dependent on gas, coal and oil — the burning of which unfortunately also fuels climate change. And of course, a lot of the countries that sell us the stuff aren’t exactly well-meaning democracies. Stupid situation.
You could easily generate electricity yourself with solar modules, very cleanly, without any CO2 emissions. Great thing, thank you, dear sun. But what has always kept me from doing it, for example: I live in rented accommodation, so I don’t have my own roof, and I also always thought that it was ridiculously complicated, with all sorts of weird applications and waiting for permits and so on and so forth. Well, maybe that’s not true, isn’t it all that complicated? Because there is this: BALKONKRAFTWERK.
What the manufacturers of such balcony power plants promise almost sounds a bit too good: Simply plug it into the socket and green electricity flows into the apartment, the meter turns more slowly and I have to pay less. But is it really that simple? And is that legal?
Yes, absolutely, at least that’s what the fans of these balcony power plants say: according to them, anyone can simply plug a solar system with a peak output of up to 600 watts into the socket. Plug-in photovoltaic system is the official name, but in the meantime “balcony power plant” has actually become commonplace. I’m supposed to put about 700 euros on the table for it.
Yes, and 600 watts is not even that little. I took a look at what electricity I draw from the line during the day: So with the fridge, internet and all the smart home junk, I already have a base load of around 100 watts. And when the computer, coffee machine and massage chair are on, it naturally gets more. But 600 watts from the balcony power plant are definitely enough that I don’t have to buy any electricity from my electricity supplier at times — that is, when the sun is shining.
Well, if it really were that easy, why doesn’t everyone have a balcony power plant like this? What is the catch? I asked my c’t colleague Jan Mahn that — he has been working intensively on balcony power plants for a long time and even brought me one once.
interview
Yes, awesome everything. My interest is definitely aroused, I would like to have such a part, how about you? Are you interested in the topic at all? Should we make more videos on do-it-yourself electricity production? Write in the comments. And now I’m wondering how I can convince my missing person to hang something like this on my balcony. Bye!
