The so-called 2,500-hour rule is one of the special regulations for electricity-intensive companies and, like the Belt load or the Atypical grid usageregulated in § 19 StromNEV. Here too, companies have the option of setting a clearly Reduced grid fee if their electricity consumption exceeds a certain period of use and a minimum consumption. To ensure that the grid fees can be levied in a "causation-based" manner, the structure of the grid fees is determined on the basis of energy prices (for the amount of electricity consumed) and power prices (for the highest connected load used per year). This creates a defined "Inflection point at 2,500 annual usage hours", which has a direct impact on the calculation of costs for grid users.
Background and aim of the 2,500-hour rule
The 2,500-hour rule is based on empirical data on historical grid loads and aims to achieve a Distribution of grid costs according to causation to be guaranteed. Consumers that place an uneven load on the electricity grid due to high peak loads also contribute more to the grid's fixed costs. The Simultaneity functionwhich models a user's contribution to the grid peak, provides for a gradual linear adjustment. If usage exceeds 2,500 hours per year, there is a transition to higher charges, which in practice leads to a differentiation of the grid charges into two items: Work and power prices vary depending on whether the 2,500 hours are exceeded. The aim of the regulation is to relieve companies with more even load profiles, while at the same time users with irregular or high peak loads bear the costs they cause.
Requirements for the 2,500-hour rule
In order to benefit from the 2,500-hour rule, electricity-intensive companies must meet two key requirements. Firstly, the annual electricity consumption at a single consumption point must be at least 10 GWh must amount to. Secondly, a so-called utilization period - i.e. the ratio of annual work to simultaneous highest power drawn - from at least 2,500 hours to be demonstrated. These criteria are aimed at providing targeted relief to companies with a consistently high energy demand and even capacity utilization. An application for a reduced individual grid charge can only be submitted if both conditions are met at the same time.
Individual grid fee reductions
If a company fulfills the requirements of the 2,500-hour rule, it is possible to Individual grid charge with the responsible grid operator. The fee is not reduced across the board, but is based on Basis of actual use of the grid, in particular taking into account uniform capacity utilization. The agreement is subject to approval by the Federal Network Agency and enables electricity-intensive companies to Customized relief in the grid fees. The aim is to reduce the economic burden on companies with consistently high electricity consumption without losing sight of the system costs for all grid participants. The resulting loss of revenue for grid operators is passed on to all electricity consumers via the nationwide §19 surcharge. This surcharge for special grid usage was 0.643 ct/kWh in 2024 and was increased to 1.553 ct/kWh in 2025.
Legal basis of the 2,500-hour rule
The basis for the 2,500-hour rule is Section 20 of the Energy Industry Act (EnWG) and the basis for its calculation is set out in the Incentive Regulation Ordinance (ARegV). The relief is ultimately anchored in Section 19 (2) sentence 2, in Section 19 StromNEV levy and in StromNEV Annex 4 to Section 16 (2), which stipulates that the lower usage duration range of the simultaneity function is between 0 and 2,500 annual usage hours. The upper usage duration range starts at 2,500 annual usage hours and ends at 8,760 annual usage hours. The respective grid operators (DSOs) calculate the grid charges accordingly and must comply with these framework conditions:
- the degree of simultaneity with an annual usage period of zero hours is a maximum of 0.2
- the two straight lines describing the degree of simultaneity intersect at a point defined by the annual usage period of 2,500 hours
- the degree of simultaneity for an annual usage period of 8,760 hours is 1.
Calculation of the annual hours of use
The Annual hours of use - also Full utilization hours are the central technical benchmark for the 2,500-hour regulation. Their calculation is based on the ratio of the annual electricity consumption (in kWh) to the maximum power consumption (in kW). In other words, the ratio between the annual electricity consumption and the maximum peak load of a consumer. It serves as an indicator of how evenly a consumer loads the grid. High load peaks therefore shorten the duration of use and the smoothing of load peaks (peak shaving) extends the duration of use. From the kink point at 2,500 hours, users with less than 2,500 hours of use pay higher labor prices (per kWh), while users with more than 2,500 hours of use higher service prices (per kW) must be paid.
Battery storage for grid charge optimization with the 2,500-hour rule
The use of Large battery storage systems plays a role in the Network fee optimization The 2,500-hour rule plays a dual role. Energy-intensive companies with large storage facilities in particular benefit from a classification above 2,500 hours of use. In this area, the power prices are proportionally higher. Through the targeted reduction of peak loads (Peak Shaving), the Reduce maximum removal rate.
As the duration of use is calculated as a quotient of annual consumption and peak power, large-scale battery storage systems can, on the other hand, enable access to the 2,500-hour regulation in the first place or increase its effect. Companies that are currently below the 2,500-hour limit can use storage to smooth out their peak loads and increase the constant hours of use.
Criticism of the regulation
The current structure of grid fees in Germany distinguishes between energy prices and demand charges. However, the current grid fee regulation hinders the use of Flexible power consumer in industry, critics note. Although these technologies could be used specifically for high levels of electricity generation from renewables, existing grid fees create false incentives: they reward the greatest possible use of renewable energy. Consistent power consumption (e.g. through high service charges for short periods of use), which makes flexible use economically unattractive. Rigid threshold values for usage hours (e.g. 2,500 h or 7,000 h) are particularly critical, as high additional costs can arise if these are not reached. The fees are also heavily dependent on the Location dependent - partly random - and do not reflect the actual system benefits. Overall, the current regulations therefore inhibit investment in flexible, climate-friendly technologies.
Conclusion: Between incentive and need for adjustment
The 2,500-hour regulation is an effective instrument for reducing grid fees for electricity-intensive companies - provided that the technical and legal requirements are met. It rewards an even load on the grid and creates incentives for greater energy efficiency and investment in technologies such as battery storage or load management. At the same time, however, it is also clear that the regulation is based on rigid threshold values and does not always reflect the actual benefit to the grid. In times of increasing flexibility through renewable energies and controllable consumers, the discussion about the further development of the grid fee structure is becoming increasingly relevant. In order to create investment-friendly framework conditions in the long term, targeted adjustments are therefore necessary to better reconcile system responsibility, flexibility and economic efficiency.