The Federal Network Agency is planning to set „Market integration of storage and charging points (MiSpeL) a crucial switch for the future of electricity storage. Until now, the rule has been: Only if a storage device exclusively with renewable electricity Once electricity has been fed into the grid, the resulting grid feed-in can receive EEG (Renewable Energy Sources Act) funding. As soon as grid electricity is also fed in – for example, to take advantage of favorable prices on the spot market – the eligibility for funding is completely lost.
The existing exclusivity option according to § 19 Abs. 3a EEG, which previously excluded the use of charging stations for storage, is now up for debate and is to be dropped with MiSpeL. In the future, storage systems will be able to absorb both renewable energy and grid electricity simultaneously without the EEG feed-in tariff for the renewable portion being lost. Through the Use of „mixed current“ open up new Flexibility potentials for operators of power storage systems and charging points.
New options for demarcation by MiSpeL
Provided that the relevant documentation and delimitation requirements are met, the Federal Network Agency proposes two methods for distinguishing between eligible (renewable energy electricity) and balanceable (grid electricity) quantities:
1. Accrual optionAllows for a mathematically exact quarter-hourly allocation of energy quantities based on clearly defined formulas. This option is particularly relevant for operators of large storage and PV systems with high flexibility requirements who wish to leverage the full potential of electricity trading arbitrage and schedule optimization.
High accuracy, but increased measurement and billing effort.
→ Practically relevant for larger storage facilities and professional operators.
2. Package optionSimplified procedure for smaller facilities as well as operators who prefer simplified processes. The billable electricity quantities are assigned on a flat-rate basis.
Only for small systems up to 30 kWp.
Not applicable for large-scale industrial storage.
For companies with a PV system and Large-scale battery storage is the new delimitation function the key to greater flexibility. In the future, you can use your storage as well Self-consumption optimization as well as participating in German electricity market install without losing eligibility for EEG subsidies.
Simplifications for bidirectional charging
Another aspect of the MiSpeL design concerns Vehicle-to-Grid (V2G) and bidirectional charging.Charging points for electric cars will be regulated in the same way as stationary batteries in the future. They can be used according to the same principles for optimizing self-consumption and participating in the energy market. This creates an even larger flexibility reserve in the system. This also greatly facilitates the integration of storage technologies into intelligent energy management systems.
New Applications for Battery Storage through MiSpeL
The mixed-current operation made possible by MiSpeL opens up new application areas for companies with large battery storage systems. In addition to the intermediate storage of their own renewable generation, it will be possible to store grid electricity during times of particularly low prices and to sell it back at higher prices later. This additional flexibility increases profitability, since large storage systems not only contribute to optimizing self-consumption but also actively react to electricity market prices and Power trading can be used. At the same time, they make an important contribution to the integration of renewable energies by smoothing out generation and load peaks.Peak Shavingto cushion and shift loadsLoad shiftingWith the new delimitation option, operators will also, for the first time, receive a clear, legally sound framework for the Parallel use from renewable electricity and grid electricity in storage operation – a crucial step for planning security of future storage investments.
Classification of the new MiSpeL rules for storage
The draft implements provisions of the Electricity Storage Act, which aims in particular to avoid temporary generation surpluses and to better integrate electricity from renewable energies into the market. The previous „all-or-nothing“ rule is to be abolished. Instead, the new demarcation allows storage to be used more broadly economically and its flexibility to be specifically marketed. This increases the attractiveness of large-scale storage not only for self-consumers but also for operators who want to participate in electricity and flexibility markets.
However, it remains open how MiSpeL rules will be reconciled with discussions about Network Charge Reform (AgNes) intermeshes. The Federal Network Agency expressly points out that the issue of grid fee privileges is not part of the MiSpeL determination. For companies, this means: MiSpeL clearly improves the market integration of storage. However, relief from grid fees will be decided in separate proceedings.
The determination procedures are ongoing until the end of October 2025; feedback from practitioners – particularly from companies and associations – is expressly welcome. Overall, MiSpeL opens up new revenue streams through arbitrage, grid services, and optimized schedules, which sustainably strengthens the economic viability and system integration of large battery storage systems. At the same time, regulatory and settlement barriers are to be removed.
An update on the topic can be found in our post: “MiSpeL regulation decided: What battery storage systems in industry and commerce are now allowed“.