Balcony Power Plant & EEG: Metering & Grid Feed-in Rules Explained

The increasing adoption of renewable energy sources, particularly photovoltaic (PV) systems, is creating new complexities for homeowners and grid operators alike. A recent discussion highlights a scenario where individuals with existing renewable energy installations, such as those covered by Germany’s Renewable Energy Sources Act (EEG), are adding smaller systems like balcony power plants. This combination can lead to situations where energy is drawn from the grid – supplied by providers like BKW – even while the homeowner is generating surplus power, raising questions about fair accounting and potential overcharging.

The core issue revolves around accurately measuring and accounting for all energy flows – energy generated by the homeowner’s systems, energy consumed by the household, and energy imported from the grid. Currently, the standard setup often doesn’t adequately capture instances where a homeowner is simultaneously generating power and importing a little amount from the grid to cover immediate demand or system inefficiencies. Here’s particularly relevant as Germany continues to incentivize the expansion of renewable energy capacity, aiming for a significant increase in the proportion of electricity generated from sustainable sources. The Bundesnetzagentur, Germany’s Federal Network Agency, took over responsibility for regulating these connections at the end of July 2022, following changes to the EEG 2021 (§ 85 EEG), reinforcing the legal right of those seeking grid connection (“Anschlussbegehrende”) to have their renewable energy systems prioritized (§ 8 EEG).

The Challenge of Bi-Directional Energy Flow

Traditionally, electricity meters measure energy flowing in one direction – from the grid to the consumer. Still, with the rise of distributed generation, energy can flow in both directions. When a homeowner generates more electricity than they consume, the surplus is typically fed back into the grid, and they may receive compensation through mechanisms like direct marketing, as offered by companies like BKW. However, if a homeowner’s consumption briefly exceeds their generation, even a small amount of energy may be drawn from the grid. Without proper metering, this imported energy can be overlooked, leading to inaccurate billing.

The concern raised by one homeowner, as detailed in a recent online forum, is that grid operators may apply a standardized deduction – in their case, 950 kWh annually – to account for potential grid imports. While this deduction might amount to a relatively small sum – approximately €65 per year based on current energy prices – the homeowner prefers a more precise accounting method. This preference is understandable, as a fixed deduction doesn’t reflect actual energy usage and could result in an overestimation of grid imports.

Required Metering and System Configuration

The solution, according to experts and forum discussions, involves installing an additional, calibrated meter to specifically measure the energy imported from the grid when the homeowner’s renewable energy systems aren’t fully meeting demand. This meter needs to be installed in a specific configuration to accurately capture the energy flow. As one forum user, “berny,” outlined, the setup would typically involve: Hausanschluss (main connection) – Zähler_Netzbetreiber (grid operator’s meter) – Einspeisung_Solar (solar feed-in) – Eigener_Zähler (own meter) – Haus+BKW (house + BKW). The grid operator’s meter continues to measure overall consumption and feed-in to the grid, while the homeowner’s meter specifically tracks energy drawn from the grid when the renewable sources are insufficient.

Crucially, the homeowner’s meter must be “phasensaldierend,” meaning it accurately measures the difference between energy generated and energy consumed on each phase of the electrical system. This ensures that the measurement reflects the actual net energy flow. Another forum user, “pvstrom,” emphasized this requirement, noting that acceptance of such a meter is not guaranteed and depends on the local grid operator’s policies.

Installation and Costs

While the cost of a calibrated meter itself is relatively modest – around €100 – the installation process can be more complex. The installation typically requires modifications to the electrical panel and should be carried out by a qualified electrician, even if the work is done within the non-sealed section of the panel. This is to ensure compliance with safety regulations and accurate meter readings.

The Bundesnetzagentur highlights the importance of digitalization and standardization in streamlining the grid connection process for renewable energy systems. New legal requirements, effective January 1, 2025 (§ 8 Abs. 7 EEG), aim to simplify and accelerate the processing of grid connection requests. This suggests a move towards more standardized procedures and potentially, greater acceptance of advanced metering solutions.

Direct Marketing and EEG Compensation

For homeowners participating in direct marketing programs, such as those offered by BKW, the situation is further nuanced. Direct marketing allows renewable energy producers to sell their electricity directly on the market, receiving a market premium from the grid operator and a monthly market value payment from the marketing company. This arrangement provides a financial incentive for generating renewable energy, but it also requires accurate measurement of both generation and consumption to ensure fair compensation. BKW assures customers of a secured EEG compensation, receiving the market premium from the grid operator and the monthly market value from BKW, with transparent cost calculations based on a per-megawatt-hour fee.

Navigating Regulatory Changes and Future Developments

The regulatory landscape surrounding renewable energy is constantly evolving. The “Easter Package” introduced by the German government in 2022, and the subsequent “Solar Package” in May 2024, have introduced new requirements for standardizing and digitizing the grid connection process, particularly for smaller EE-Anlagen up to 30 kW. These changes are intended to reduce bureaucratic hurdles and accelerate the deployment of renewable energy systems. A detailed guide to implementing these legal requirements is available from the BDEW (German Association of Energy and Water Industries).

The situation described by the homeowner underscores the need for clear communication and standardized procedures regarding grid connection and energy accounting. As more households adopt renewable energy technologies, grid operators and policymakers must ensure that billing practices are fair, transparent, and accurately reflect the bi-directional flow of energy. Accurate metering is paramount to achieving this goal and fostering greater consumer confidence in the transition to a sustainable energy future.

The next key development to watch will be the full implementation of the new regulations outlined in the EEG and the associated guidelines from the Bundesnetzagentur and BDEW. Homeowners considering installing or upgrading their renewable energy systems should consult with their local grid operator and a qualified electrician to ensure compliance with the latest requirements and to determine the most appropriate metering solution for their specific needs. Further information and updates can be found on the Bundesnetzagentur website: https://www.bundesnetzagentur.de/DE/Fachthemen/ElektrizitaetundGas/ErneuerbareEnergien/Netzanschluss/start.html

Have you encountered similar challenges with grid connection and energy accounting for your renewable energy systems? Share your experiences and insights in the comments below.