Photovoltaics (PV) has long been a key component of sustainable energy generation. With falling costs for PV systems and rising electricity prices, the use of solar energy is becoming more and more attractive. More and more people are therefore interested in investing in their own solar system.
To ensure that you start your personal energy transition successfully and legally, there are a few important points to consider.
In this article, we answer the most frequently asked questions about the purchase and operation of a photovoltaic system – and shed light on current political developments and the legal framework in energy law.
Energy law is a dynamic, constantly changing field. Therefore, this article can provide general information but cannot replace individual advice.
For a specific case analysis and individual advice, we would be happy to offer you an initial consultation with our specialized energy law attorneys.
Who is considered the operator of a photovoltaic system?
The Renewable Energy Sources Act (EEG) specifies the term "plant operator" in Section 3 No. 2: According to this, a plant operator is anyone who, regardless of ownership, operates the plant to generate electricity from renewable sources or mine gas. The legal responsibility for operating the plant therefore does not necessarily lie with the owner, but with the person who uses the electricity generated.
This regulation clarifies that the plant operator bears the economic burden. He is responsible for assuming the operating costs and the financial risk. He also has the right to use the plant on his own account, which means that he can use the electricity generated himself or sell it.
Interestingly, the operator role is decoupled from the legal ownership of the plant. This is particularly relevant in cases where plants are leased, for example. Self-supply of electricity, where electricity production and consumption are in the hands of the same person, is another aspect that underlines the importance of the operator position. These principles are equally valid for operators who themselves consume the electricity they generate.
Legal classification of a contract for the purchase, delivery and installation of a photovoltaic system
The legal nature of contracts for the purchase and installation of a photovoltaic system was unclear for a long time, which caused significant uncertainty for consumers. The decisive factor is whether the contract is classified as a purchase contract or a work contract, as this results in different legal consequences.
If separate contracts are concluded for purchase, delivery and assembly, these are independent agreements that can each be considered individually. This simplifies legal handling as there is no need for complex classification.
In many cases, however, a "complete package" is offered that includes both the installation and commissioning of the photovoltaic system. With such a mixed contract, a clear separation is not legally possible, and a decision must be made as to whether the contract should be treated primarily as a purchase contract in accordance with Section 433 of the German Civil Code (BGB) or as a work contract in accordance with Section 631 of the German Civil Code (BGB). This classification is based primarily on whether the construction work or the delivery of the system is the main focus. If the installation is only a supplementary service to the delivery, the purchase contract dominates.
For consumers, the law on sales often offers more advantages, such as the right to choose between remedying defects and delivering a new product within the scope of the warranty in accordance with Section 439 Paragraph 1 of the German Civil Code (BGB). The warranty period for sales contracts is typically two years, but for work contracts it is five years - or four years for contracts under the VOB.
Especially for in-roof systems that have construction material-related aspects of the work contract, a five-year warranty period could even be applicable.
Practical tip: For a typical "rooftop photovoltaic system", a purchase contract is often assumed, since installation plays a subordinate role here. Despite the possibility of individual contract adjustments, general terms and conditions (GTC) of a company that attempt to circumvent the purchase law are often ineffective against consumers.
When is a photovoltaic system considered delivered?
The point in time at which a PV system is considered “delivered” depends on the contractual agreements.
If the seller has undertaken to assemble the equipment, install it in a ready-to-use state and provide an introduction to its operation, the equipment will not be considered delivered until these steps have been completed.
Case law stipulates that the buyer only has the opportunity to inspect the technical system after it has been completely assembled, installed and instructed (cf. BGH NJW 1961, 730).
It is therefore crucial that the buyer is given the opportunity to inspect the system after it has been fully commissioned.
Commissioning of a photovoltaic system: significance and costs in energy law
The energy law definition of the commissioning of a photovoltaic system (PV system) according to Section 3 No. 5 of the Renewable Energy Sources Act (EEG) describes the “initial commissioning of the system exclusively with renewable energy or mine gas after it has been made technically ready for operation”. In concrete terms, this means:
The PV system must be permanently installed at the intended location, for example on a roof, and equipped with all the necessary accessories for generating electricity. However, the mere production of electricity is not enough to speak of completed commissioning. The system is only officially in operation when the electricity is fed into the public grid, temporarily stored in a storage facility or consumed directly.
Commissioning date of a PV system: The commissioning date marks the point in time at which the system is fully installed and the electricity generated is actually used, whether through feed-in, direct consumption or storage. This point in time is critical because it determines the start of the remuneration period for electricity fed into the grid according to the EEG.
Important practical tip: Commissioning should always be carried out by a qualified electrician. This specialist checks and documents the proper operating status of the system. It is also advisable for customers to document the commissioning process precisely in order to be able to assert any claims.
Costs of commissioning a PV system: The costs for the installation and actual commissioning of a standard rooftop PV system vary depending on the size and specific site conditions and are between around €1,500 and €3,000. In addition to these initial costs, there are ongoing expenses such as insurance premiums or reserves for maintenance and repairs, which can run into the three-digit range annually. The acquisition costs for the system and accessories are not included in these amounts.
Delivery times for photovoltaic systems: What you should know
Delivery times for a photovoltaic system vary and average between 2 and 4 months. The time until delivery is influenced by several factors, including the customer's geographical location, the choice of supplier and the availability of the components required for installation.
Experts expect delivery times to ease in the future. Supply chains have stabilized, especially compared to the challenges that arose during the Corona pandemic and at the beginning of the Ukraine conflict. Despite the general improvement, however, delays can still occur. These are often due to increased demand for specific components or the limited availability of skilled craftsmen at the respective location.
Who pays the costs for grid connection and grid expansion for a photovoltaic system?
The financial responsibility for the grid connection of a photovoltaic system lies with the system operator. According to Section 8 Paragraph 6 of the Renewable Energy Sources Act (EEG) 2023, the grid operator must provide a concrete schedule for the grid connection and a detailed cost estimate within eight weeks as soon as it has received all the necessary information from the system operator.
While the costs for the actual connection of the plant to the grid are borne by the plant operator, the grid operator usually assumes the costs for necessary expansions of the grid. This regulation ensures that the infrastructure costs are not passed on exclusively to individual plant operators, but are borne by the grid operator company, which ensures a fair distribution of the burden in the sense of promoting renewable energies.
Delay in commissioning a photovoltaic system: rights and compensation
Setting a contractual delivery date for your photovoltaic system is essential to ensure planning security and to assert possible claims for damages in the event of delivery delays.
Procedure if delivery date is missing: If no delivery date was originally agreed, it is advisable to set one retrospectively. This allows you to transfer responsibility for any damage caused by late delivery to the seller.
Legal consequences of non-compliance: Failure to meet delivery deadlines will result in the seller being in default - regardless of whether subcontractors have been commissioned. In such a case, the seller may be required to compensate for the negative effects of the delayed commissioning. However, claims for damages due to delay must be examined on a case-by-case basis.
Compensation for delayed completion of a PV system: Claims for damages due to late delivery are based on the situation you would have reached without the delay. This includes, for example, lost feed-in tariffs or increased costs for self-consumption if the PV electricity is only available late. The Munich Higher Regional Court has ruled that lost profits can be determined even without extensive expert reports if an average value for electricity generation can be derived (case no. 28 I 452/19).
Claim for damages against the network operator: The grid operator is obliged to connect the PV system to the public grid. If there are delays in the grid connection and the system remains unused as a result, disadvantages can arise. The prerequisite for compensation is that all technical requirements for the grid connection are met. From this point on, the grid operator is obliged to connect "immediately" in accordance with Section 8 EEG 2023. If the delay is the responsibility of the grid operator, claims for damages are possible in accordance with Sections 280 ff. of the German Civil Code (BGB).
Practical tip: To avoid delays in the grid connection, it is advisable to apply for it early and, if necessary, to coordinate this process with the support of the installation company. If the grid connection is part of an "all-inclusive PV package", the provider is responsible for any delays and must deal with the grid operator in the event of problems.
Energy law attorney: support with the purchase and commissioning of your solar system
The purchase and commissioning of a photovoltaic system (PV system) is associated with legal challenges that often only become apparent in detail. Our specialized energy law attorneys are at your side and help you avoid legal pitfalls - from drafting contracts to solving delays.
- Legal advice on the purchase contract for solar systems
- Delay in the delivery and commissioning of your PV system
- Specialist lawyers for energy law: compensation and warranty
With our expertise in energy law, you are legally protected when purchasing and installing your solar system. Contact us for in-depth advice!
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