MiSpeL

MiSpeL is the market integration process of the new paragraph §19 EEG introduced with the Solar Peak Act that allows market integration of storage systems and EV charging points in Germany. It replaces the exclusivity option and allows bidirectional operation, energy arbitrage and flexible use of hybrid PV and battery systems. The regulation aims to simplify administration and bureaucracy through a flat-rate option for small PV prosumers while supporting grid stability and smart energy management.

What is MiSpeL?

MiSpeL, short for “Market Integration of Storage and Charging Points", is the German market integration process defined under §19 of the Renewable Energy Act (Erneuerbare-Energien-Gesetz, EEG). The amendment was introduced in February 2025 while the market procedure started in September 2025. It was developed by the Federal Network Agency (Bundesnetzagentur, BNetzA) to enable the market integration of energy storage systems such as battery energy storage systems (BESS) and charging points. MiSpeL replaces the previous exclusivity option (Ausschließlichkeitsoption) that only allowed storage systems to charge from renewable sources and introduces two different models: the Abgrenzungsoption and the Pauschalmodell.

MiSpeL allows the bidirectional operation of batteries in hybrid plants that combine renewable energy sources such as PV or wind with the public grid. It enables energy arbitrage and bidirectional charging by allowing stored electricity from both renewable generation and the grid to be used flexibly. Before MiSpeL, hybrid installations such as PV plus batteries could only feed 100 percent renewable electricity into the grid. The goal of MiSpeL is to enable flexibility use cases from decentralized systems and to align them with market conditions and grid requirements. 

Core concept of MiSpeL

Traditionally, storage systems such as home batteries or EVs could be charged from renewable sources or the public grid. However, under the exclusivity option (Ausschließlichkeitsoption), only electricity that was 100 percent renewable could be fed back into the grid while retaining EEG subsidies. Any electricity stored from the grid or mixed sources lost its subsidy when injected into the grid. This restriction limited flexibility and made energy arbitrage impossible. The exclusivity option therefore prevented bidirectional use, such as buying electricity at low prices and selling it at high prices, even for prosumers, resulting in an administratively complex and inflexible system.

With MiSpeL, however, bidirectional use is now possible. MiSpeL allows for bidirectional energy flows between renewable sources, storage units and the electricity grid. This means that system owners or prosumers can buy electricity from the grid when prices are low, for example at night or during periods of overproduction, store it locally in a battery or charge their EV, and either feed the stored energy back into the grid when prices are high or use it to cover their own demand.

With this change, prosumers become active market participants who can act based on price signals rather than only on PV generation. To benefit from the flat-rate option, direct marketing of the electricity is required, allowing operators to participate in the market while receiving the defined subsidies. This enables market-based operation of batteries and charging infrastructure while also supporting grid stability through flexible feed-in and withdrawal, encouraging smart energy management that optimizes charging and discharging based on real-time prices.

Implementation process of MiSpeL 

The implementation of MiSpeL is directed by the BNetzA under §19 EEG as part of the Solarpaket I. It aims to define a technical and legal framework for integrating storage systems and charge points into the electricity market while maintaining compliance with the renewable energy act. This process must be completed by July 2026 with the market rollout being expected in late 2026 to early 2027. The development includes public consultations and collaborations with grid operators, energy companies and industry stakeholders to ensure transparent and practical regulation. 

The implementation focuses on defining measurement and billing requirements for bidirectional systems and clarifies how the two integration options, the deferral option (Abgrenzubgsoption) and the flat-rate option (Pauschaloption) are to be applied. It also creates a clear reporting and verification procedure for storage and feed in volumes, reducing administrative complexity. 

Once finalized, MiSpeL will replace the exclusivity option in Germany and will be the standard framework for market integrated storage systems and charging infrastructure. As this transition requires digital and metering solutions that can handle the data exchange and compliance with BNetzA standards.

MiSpeL deferral and flat-rate options

MiSpeL defines two options for integrating storage systems and charge points into the electricity market: 

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• The deferral option requires precise measurements and separation of electricity flows, meaning that all energy fed into the grid locally must be accurately allocated between renewable sources and grid electricity. It requires two 15-minute iMSys smart meters: one to measure the renewable energy feed-in and one to track electricity from the grid that is cycled through the battery. This setup allows exact tracking for subsidy eligibility but makes the option more complex to implement.

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• The flat-rate option is a simplified, flat-rate calculation suitable for smaller systems and prosumers. It assumes that up to 500 kilowatt hours (kWh) per kilowatt peak (kWp) of installed PV per year are eligible for subsidies. Any feed-in beyond this limit loses subsidy eligibility but is still subject to discounted taxes, levies, and grid fees. This option only requires a single bidirectional smart meter at the grid connection point and minimizes technical and administrative efforts. It also enables operators to benefit from energy arbitrage and bidirectional operation without complex allocation calculations.

Sample calculation under MiSpeL

To show the proper benefits of MiSpeL and how the regulation can look in action, we created a sample calculation below. 

Setup

• PV system: 10 kWp
  
  
• Battery storage: 10 kWh (bidirectional)
  
  
• Flat-rate limit: 500 kWh per kWp per year → 10 × 500 = 5,000 kWh maximum subsidy-eligible feed-in
  
  

Scenario 1 – Feed-in below limit

• Measured total feed-in: 4,500 kWh
  
  
• Measured total grid consumption: 2,000 kWh
  
  
• Since feed-in (4,500 kWh) < flat-rate limit (5,000 kWh):
  
  
  
  • Subsidy-eligible feed-in: 4,500 kWh
    
    
  • Saldierungsfähige feed-in: 0 kWh
    
    
  • Grid consumption billed normally: 2,000 kWh

In Scenario 1, total feed-in is 4,500 kWh, which is below the limit, so the entire amount is subsidized. Grid consumption is billed normally.

Scenario 2 – Feed-in above limit

• Measured total feed-in: 8,000 kWh
  
  
• Measured total grid consumption: 2,000 kWh
  
  
• Flat-rate limit: 5,000 kWh subsidized → remaining 8,000 − 5,000 = 3,000 kWh is saldierungsfähig
  
  
• Saldierungsfähige feed-in offsets grid consumption: 2,000 kWh of grid use can be fully offset by 3,000 kWh surplus feed-in
  
  
• Result: 5,000 kWh subsidized, 3,000 kWh saldierungsfähig, no levy on grid consumption

In Scenario 2, total feed-in is 8,000 kWh, exceeding the limit. The first 5,000 kWh is subsidized, while the remaining 3,000 kWh are treated as grid electricity and used for levy balancing. This means that while the user still pays for the 2,000 kWh of electricity consumed from the grid at their tariff rate, no levies are charged on this amount because the feed-in surplus exceeds grid consumption.

This enables bidirectional operation and energy arbitrage, allowing the system to buy electricity at low prices, and store, use or sell it when prices are higher.

MiSpeL benefits 

MiSpeL introduces several important benefits for prosumers, storage operators and the electricity system. By allowing bidirectional operation, batteries and EVs can buy electricity when prices are low, and then (as mentioned) store, use or sell it when prices are high. This enables energy arbitrage and increases economic efficiency.

The flat-rate option simplifies administration as only a single bidirectional meter is required for smaller systems. Operators can fully participate in the electricity market while still receiving subsidies for a defined portion of their feed-in.

MiSpeL also enhances grid stability. Flexible feed-in and withdrawal reduces peaks and supports the integration of renewables. The regulation encourages smart energy management and the use of dynamic tariffs, allowing operators to optimize their storage and charging points based on real-time prices.

Criticism and solutions

Although MiSpeL represents a significant step forward, several challenges and criticisms have been raised. The deferral option (Abgrenzungsoption) is technically complex and requires detailed measurements and data handling, which may be burdensome for smaller operators. Definitions for eligible storage systems and measurement standards also remain unclear. Commercial operators may benefit more than small prosumers due to economies of scale and because of the tight timeline for full implementation.

Solutions to address these challenges include automated data collection and processing to reduce manual effort and ensure compliance with measurement requirements. Optimization algorithms allow storage and EVs to capture arbitrage opportunities efficiently. Platforms that integrate real-time price signals and manage reporting can help operators fully participate in MiSpeL while minimizing administrative complexity.

Expert insights and future outlook

MiSpeL marks a shift from subsidy-driven operation toward market-driven flexibility for storage systems and charge points. In this context, hybrid systems refer to configurations that combine renewable generation such as PV or wind with battery storage and a grid connection, allowing both grid feed-in and withdrawal. These hybrid setups are likely to become the standard for prosumers and commercial sites by 2027.

The success of MiSpeL depends on digital infrastructure, real-time metering and intelligent energy management. As Irene Guerra Gil, Energy Market Expert at gridX, explains: “Active participation of prosumers in the energy markets is a great opportunity to unlock value not only for end customers through cost savings but also for companies using decentralized assets.” Looking ahead, MiSpeL could serve as a model for broader European integration of prosumers, ensuring that these decentralized assets operate in harmony with the electricity market rather than against it. Intelligent digital solutions,such as HEMS will be essential to unlock the full potential of decentralised energy systems and ensure that flexibility benefits both operators and the grid.