Photovoltaic (PV) system

A photovoltaic (PV) system converts sunlight directly into electricity and is installed on the roofs, facades, or open spaces of buildings. It is a key component of the energy transition and is subsidized by the government under the Renewable Energy Sources Act (EEG). In the real estate sector, a PV system increases the building’s energy efficiency, improves its energy performance certificate, and can significantly reduce ongoing operating costs through self-generated electricity and feeding power into the grid.

Technical Basics and System Components

A PV system consists of solar modules (silicon cells), an inverter (which converts direct current to alternating current), a feed-in meter, and optionally a battery storage unit. Roof-mounted systems on single-family homes typically have a capacity of 5-20 kWp (kilowatt-peak). With a battery storage system, excess electricity can be stored for use at night or during periods of bad weather, which increases the share of self-consumption to 60-80%.

Modern inverters can be networked with smart-home systems and enable optimized control of self-consumption-for example, by automatically charging the battery storage system during sunny hours and discharging it in the evening. Those who operate a heat pump or an electric car achieve particularly high self-consumption rates through intelligent load control.

Balcony power plants (plug-in PV) are a simplified, miniature version for renters and homeowners without roof access. They can be used with a feed-in capacity of up to 800 watts without grid registration and do not require a building permit in Bavaria-a low-threshold entry point into solar power generation.

Cost-Effectiveness and Incentives

The payback period for a PV system is currently 8-15 years, depending on the system and electricity consumption; the modules have a lifespan of 25-30 years. The feed-in tariff under the EEG is guaranteed for 20 years and currently (as of 2025) amounts to around 8-9 cents/kWh for systems under 10 kWp. Self-consumption is significantly more cost-effective: Every kilowatt-hour consumed on-site saves grid electricity at full price (30-40 cents/kWh) and is thus four to five times more valuable than a kilowatt-hour fed into the grid.

In Bavaria, PV systems are additionally subsidized through the Bavarian Solar Bonus Program and the KfW product range (e.g., Loan 270 “Renewable Energies - Standard”). The KfW loan enables financing at favorable interest rates; repayments are made from the ongoing electricity revenues. For new commercial buildings in Bavaria, a mandatory PV requirement has been in effect since 2023; corresponding regulations for residential buildings are currently being discussed in state legislation.

A concrete calculation example for Nuremberg: A 10-kWp system generates an annual average of approximately 10,000 kWh of electricity. With a 40% self-consumption rate (4,000 kWh × 35 cents) and 60% feed-in (6,000 kWh × 8 cents), this results in an annual yield of approximately 1,880 euros. With acquisition costs of approximately 15,000 euros, the system pays for itself in about eight years.

Property Value and Energy Performance Certificate

A PV system improves a building’s energy efficiency class on the energy performance certificate, which is increasingly a decisive factor in the purchase decision. Buyers are paying closer attention to expected utility costs-and a property with energy efficiency class A instead of C commands price premiums of 5-15% in the Nuremberg metropolitan region. Appraisers take into account the asset value of the system (current market value of the modules and inverters) and, if applicable, the capitalized income value of the remaining feed-in tariff period.

Important when selling real estate: The buyer must assume the feed-in contract with the grid operator and re-register the system with the Market Master Data Register (MaStR). These formalities should be clearly stipulated in the purchase agreement-specifying who is responsible for the re-registration, which documents must be handed over (system documentation, warranty certificates, maintenance contracts), and whether existing feed-in payments will be prorated. We coordinate these details as part of our sales process.

Practical Tip for Homeowners in Nuremberg and Franconia

With around 1,700 hours of sunshine annually, the Nuremberg metropolitan region is one of the sunniest regions in Germany, making PV systems economically very attractive. By comparison: Hamburg averages about 1,600 hours, and Munich about 1,800 hours of sunshine. Owners of single-family homes and townhouses in Nuremberg, Erlangen, Schwabach, or the surrounding communities should check whether the roof pitch and orientation allow for a profitable PV system. South-facing roofs with a 30-45° pitch are ideal; east-west orientation is less efficient but extends the duration of sunlight exposure throughout the day.

When selling a home, we recommend highlighting the existing PV system prominently in the listing and documenting the current yields with feed-in records. Buyers who can see the actual annual yield over the past three years gain a solid understanding of the system’s profitability. This increases the perceived value and sets the property apart from comparable listings without PV.

Frequently Asked Questions

Do I need a building permit for a PV system?

In Bavaria, rooftop systems up to a size corresponding to the roof area are generally permit-free. Larger systems, facade-mounted systems, or systems in historic preservation zones may require a permit. In Nuremberg, there are numerous neighborhoods with historic ensembles-anyone who owns a historic building there should contact the building code office and the local historic preservation authority before planning. A request to the relevant building code office clarifies the specific case and costs nothing.

What happens to the PV system when the house is sold?

The PV system is generally considered part of the building and is transferred to the buyer upon sale, provided it is permanently installed. The buyer assumes the feed-in contract and must re-register the system. Alternatively, the system can be contractually excluded from the sale-though this rarely makes sense, as the system increases the property’s value and buyers increasingly expect it. We recommend keeping all documentation related to the system (system certificate, warranty documents, grid connection confirmation) available for the buyer.

Is a battery storage system worth it in addition to the PV system?

A battery storage system significantly increases the share of self-consumption but has a longer payback period (often 12-18 years) than the system itself. It is particularly cost-effective for households with high daily consumption or an electric car. The combination of PV + storage + heat pump is considered the ideal solution for nearly self-sufficient living and is increasingly becoming standard in new single-family homes in Nuremberg. When purchasing a storage system, you should ensure sufficient capacity (typically: 10-15 kWh for a single-family home) and a warranty period of at least ten years.

How does a PV system affect your tax return?

Anyone who feeds electricity into the grid is considered a business owner for tax purposes and generates income from commercial operations. However, since 2022, a income tax exemption has applied to PV systems up to 30 kWp on single-family homes (Section 3 No. 72 of the German Income Tax Act) - retroactively effective from 2022. Additionally, sales tax on the purchase and installation is waived for private individuals (0% sales tax since 2023). The combination of these two tax simplifications has made investments in PV systems significantly more attractive. Anyone operating a system over 30 kWp or owning multiple properties should consult a tax advisor.

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