- A balcony solar system is a small solar system with one to four modules that feeds power directly into your socket. Up to 800 watts of inverter output is allowed.
- It usually costs €300 to €800 and saves about €100 to €250 a year.
- A solar system on the roof supplies 10 to 15 times as much power and can cover a large part of your consumption.
- For tenants and flats, a balcony solar system is ideal. For homeowners, a rooftop system is usually the better investment.
Balcony solar systems have become very popular in recent years – you see them on balconies, garden fences and garages. That is why many homeowners ask us: “Wouldn’t one of those small modules be enough?” The answer depends on what you want to achieve. Here we compare both solutions honestly.
What is a balcony solar system?
A balcony solar system – also called a plug-in solar device – consists of solar modules and a small inverter. The power flows through a socket into your home’s wiring and is used there directly by your appliances, for example the fridge or the router.
- Output: the inverter may feed in up to 800 watts. The modules themselves may have a combined output of up to 2,000 watts.
- Registration: you only need to enter the device in the Marktstammdatenregister (the federal register of energy installations) run by the Federal Network Agency. Registration with the grid operator is no longer required.
- Tenants and owners’ associations: since 2024, landlords and owners’ associations may only refuse a balcony solar system in exceptional cases.
Balcony solar and rooftop systems compared
| Balcony solar system | Solar system on the roof | |
|---|---|---|
| Output | up to 800 W feed-in | usually 6–15 kWp |
| Power per year | approx. 400–800 kWh | approx. 5,700–14,700 kWh |
| Share of consumption (family, 4,500 kWh) | approx. 10 % | 30 % without, 60–70 % with battery |
| Costs | approx. €300–800 | approx. €6,500–22,500 |
| Savings per year | approx. €100–250 | approx. €1,000–1,500 (10 kWp) |
| Installation | can be done yourself | by a specialist company |
| Battery, e-car, heat pump | hardly worthwhile | easy to combine |
Which option suits whom?
A balcony solar system is ideal if …
- you rent or live in a flat you own,
- you don’t have a suitable roof,
- you want to start on a small budget and gain some experience.
A rooftop system is better if …
- you own a house with free roof space,
- you want to noticeably lower your electricity bill – not just by a few per cent,
- you want to use an e-car, a heat pump or a battery now or later.
Our honest opinion: for homeowners, a balcony solar system is usually just a small start. The roof has room for ten times as much – and only a rooftop system can be sensibly combined with a battery, e-car and heat pump.
The roof check shows you in 2 minutes which system is worthwhile for your house.
What to look out for with a balcony solar system
- Direction: a south-facing spot without shade delivers the most. Hung vertically on the balcony railing, the modules yield less than when set up at an angle.
- Secure mounting: modules must stay firmly in place even in a storm. Don’t skimp on the brackets.
- Its own circuit: don’t plug the device into a multi-socket extension lead. If in doubt, have an electrician check the wiring.
- Old meter: if an old Ferraris meter runs backwards, it has to be replaced. The metering point operator takes care of this.
And if I already have a balcony solar system?
Then it is no obstacle to a rooftop system. We take it into account in the planning and work out whether it can keep running or whether it makes more sense to use the modules differently.
Conclusion
Balcony solar systems and rooftop systems are not competitors but solutions for different situations. In a flat, a balcony solar system is a good way to get your own power. In your own house, a rooftop system gets you many times more – and makes you much less dependent on rising electricity prices.
Frequently asked questions
How much electricity does a balcony solar system produce?
Depending on direction and module output, about 400 to 800 kWh a year. For a family that is around 10 % of their electricity consumption.
Do I have to register a balcony solar system?
Yes, but only in the Marktstammdatenregister of the Federal Network Agency (Bundesnetzagentur). This takes a few minutes online. Registration with the grid operator is no longer required.
Can my landlord ban a balcony solar system?
Only in exceptional cases. Since 2024, balcony solar systems have been classed as a privileged measure. However, the landlord or owners’ association may have a say in how the system is mounted.
Does TAQA Solar also install balcony solar systems?
We focus on solar systems for roofs, batteries and wallboxes. If you are unsure what suits you, we are still happy to advise you.
As of: November 2026. All prices are guide values including installation. Legal and tax information without guarantee – the laws in force apply (including UStG, EStG, EEG).
