MiSpeL in Germany: What It’s Worth for Large Scale Co-located Batteries
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Key points
- The Bundesnetzagentur adopted the MiSpeL determination on 1 October 2026, so a co-located battery can charge from the grid without the solar plant losing its market premium. Support will be kept as well for the solar share stored into the battery and re-exported.
- MiSpeL’s separation option (Abgrenzungsoption) uses quarter-hourly meter data to split a site’s exports into ‘eligible’ volumes that keep the market premium and ‘nettable’ volumes treated as stored grid power.
- Solar systems of up to 30 kWp can use a separate flat-rate option (Pauschaloption), which assigns volumes via a pre-defined assumption.
- Until the end of September 2027, a site can use MiSpeL only with the agreement of both its grid operator and its metering point operator (Bundesnetzagentur).
On this page
- What choice did co-located batteries face before MiSpeL?
- What does MiSpeL change?
- When does MiSpeL apply?
- What is MiSpeL worth for a co-located battery?
- What should developers weigh up before using MiSpeL?
- What does MiSpeL mean for new and existing projects?
- Frequently asked questions
On 1 October 2026 the Bundesnetzagentur, Germany’s regulatory office, published its Marktintegration von Speichern und Ladepunkten (MiSpeL) regulation, a policy which allows a renewables co-located (or “green”) German battery to charge from the grid without costing the co-located solar plant its market premium.
In this blog, we’ll explain what changes MiSpeL brings with it, how the new accounting works, and what it is worth - using Gridcog to model a typical front-of-meter site.
What choice did co-located batteries face before MiSpeL?
A battery sharing a grid connection point with a subsidised renewable plant has previously had two options:
- Green. Charge only from the renewable asset and keep the market premium on everything exported. That is the exclusivity principle in section 19(3a) of the Renewable Energy Sources Act (EEG), and is the basis for co-located storage in innovation auctions.
- Grey. Import from the grid and earn merchant revenue, but lose EEG eligibility on all exports, including the part that came from the renewable asset.
The problem for the grey battery is traceability. Once grid electricity enters a battery, it mixes with stored solar energy, and under the old rules there was no recognised way to say how much of a later export was green. The law therefore treated any grid charging as contaminating the whole site’s output.
What does MiSpeL change?
MiSpeL adds a third route with the Abgrenzungsoption (separation option). Here, mixed charging is allowed, with eligible and nettable volumes calculated from quarter-hourly meter data. Put simply, the separation option provides an alternative to the old “all or nothing” setup with a calculation. Every 15 minutes, metered flows into and out of the battery are used to work out how much of what leaves the site originated from the solar plant. That share keeps its EEG market premium (the “eligible” volume). The share that originated from the grid is treated as stored grid power (the “nettable” volume).
For smaller solar with up to 30 kWp, there is a separate flat-rate option (Pauschaloption), which assigns volumes via a pre-defined assumption. The flat-rate option is aimed at households and small commercial rooftops, where installing and settling detailed metering would be disproportionate.
The separation option accounting also serves behind-the-meter co-located batteries. Levies and surcharges apply to everything imported from the grid, even if that energy is exported again. MiSpeL excludes those volumes, removing the non-commodity cost of arbitrage.
When does MiSpeL apply?
The Bundesnetzagentur opened the MiSpeL proceeding in July 2025, consulted on key principles, and published a revised working draft in August 2026 before adopting the final determination on 1 October 2026.
Adoption does not mean every site can switch on day one; the determination includes a transition period running to the end of September 2027, giving grid operators and metering point operators time to implement the new processes. During that window, a site can already use MiSpeL, but only with the agreement of both its grid operator and its metering point operator.
To be eligible to apply to MiSpeL, you need an EEG plant that is paid the market premium, meaning subsidised direct marketing (geförderte Direktvermarktung mit Marktprämie). Plants on the fixed feed-in tariff cannot use either MiSpeL option. Plant operators must also meet a set of metering and balancing conditions.
What is MiSpeL worth for a co-located battery?
In this model, we are focusing on the Front-of-Meter case. We ran three scenarios in Gridcog, with a 10MW, 2-hour BESS co-located with a 12MWp DC (10 MWac) solar asset, with the last 12 months market prices (Sep '25 - Sep '26) and a 60 €/MWh EEG subsidy.
MiSpeL keeps EEG subsidies for the energy that originally came from the co-located renewable asset, while allowing for additional merchant arbitrage through grid import. In comparison to the traditional green case, this increases revenues and works the battery harder, with more cycling through the low-yield winter months.
What should developers weigh up before using MiSpeL?
The revenue case is strong, but a few practical points will shape how quickly sites can benefit:
- Metering and data. The separation option relies on quarter-hourly measurements at the right points on site. Existing projects may need metering upgrades before they qualify.
- Operator cooperation. Until the end of September 2027, using MiSpeL requires sign-off from both the grid operator and the metering point operator, so early engagement will matter.
- To be eligible to apply to MiSpeL, you need an EEG plant that is paid the market premium, meaning subsidised direct marketing (geförderte Direktvermarktung mit Marktprämie).
- Connection limits. Grid charging and solar export share the same connection point, so import capacity and any connection agreement constraints will cap how much extra trading is possible.
Each of these can be tested in a model before committing capital. Gridcog lets developers compare green, merchant and MiSpeL operating strategies side by side for a specific site, using real market prices and asset parameters.
What does MiSpeL mean for new and existing projects?
With MiSpeL, developers can unlock the full upside of a co-located battery without giving up the EEG subsidy, making it the most attractive of the three options on the table.
For new projects, MiSpeL changes how co-located batteries should be sized and specified from the outset: a battery that can trade year-round may justify more capacity or duration than one limited to shifting solar. For existing green sites, it opens a route to extra revenue from assets already in the ground, once metering and operator agreements are in place.
If you’re keen to discuss this topic in more detail, reach out to our team.
Talk to our team Gridcog for asset developers
Frequently asked questions
What does MiSpeL stand for?
MiSpeL stands for Marktintegration von Speichern und Ladepunkten: the market integration of storage and charging points. It is a determination (Festlegung) by the Bundesnetzagentur, adopted on 1 October 2026, that sets out how electricity storage and bidirectional charging points can use grid electricity while keeping the support paid on the renewable electricity they store.
What is the exclusivity principle in section 19(3a) EEG?
It is the rule that a battery co-located with a subsidised renewable plant keeps the EEG market premium only if it charges exclusively from that plant. If the battery charges from the grid, all its export loses eligibility for the EEG support. MiSpeL does not remove this route. The Bundesnetzagentur lists the exclusivity option alongside the two new MiSpeL options, so green-only operation remains available.
What is the difference between the separation option and the flat-rate option?
The separation option (Abgrenzungsoption) is available to all users: storage and charging points are measured on a separate meter, and eligible and nettable volumes are calculated from quarter-hourly data. The flat-rate option (Pauschaloption) is only for solar systems of up to 30 kWp. It needs just a quarter-hourly meter at the building’s grid connection and has a flat-rate eligibility limit of 500 kWh per kWp.
Does MiSpeL apply to batteries co-located with wind?
Yes. The Bundesnetzagentur’s background paper names co-located storage next to a wind turbine, as well as next to a ground-mounted solar plant, as an example of where MiSpeL can be used. Wind sites would use the separation option, because the flat-rate option is only for solar systems of up to 30 kWp.
When can a site start using MiSpeL?
From 1 October 2026, with consent. During a transition period running to 30 September 2027, a site can use either MiSpeL option only if both its grid operator and its metering point operator agree. The flat-rate option must also wait for European Commission state-aid approval of its legal basis before it can be used.
Can existing co-located batteries switch to MiSpeL?
Yes, once metering and operator agreements are in place. For existing green sites, MiSpeL opens a route to extra revenue from assets already in the ground. Existing projects may need metering upgrades before they qualify for the separation option, and until 30 September 2027 they also need sign-off from both the grid operator and the metering point operator. Existing assets also need an EEG plant that is paid subsidised direct marketing premium scheme, and not the fixed, feed-in tariff, to be eligible to apply to MiSpeL.
Which charges does MiSpeL remove from stored grid electricity?
Levies on grid electricity that a battery stores and later feeds back into the grid. Under MiSpeL, no levies are due on the re-exported volume, and through legal cross-references the same relief extends to network charges and other price components. Storage losses linked to the re-export can also be counted. Grid electricity used on site for other consumption still pays all levies and network charges.
Does MiSpeL cover electric vehicles and bidirectional charging?
Yes. MiSpeL covers bidirectional charging points as well as stationary batteries, so vehicle-to-home and vehicle-to-grid set-ups keep their support even when the car battery has also charged from the grid. The Bundesnetzagentur assesses the charging point rather than each vehicle, and levies and network charges fall away on electricity fed back into the grid.
Sources
- Bundesnetzagentur, ‘Bundesnetzagentur erlässt Festlegung zur Marktintegration von Stromspeichern und Ladepunkten (MiSpeL)’, press release, 1 October 2026
- Bundesnetzagentur, ‘Festlegung zur Marktintegration von Speichern und Ladepunkten (MiSpeL)’, determination page, accessed 6 October 2026
- Bundesnetzagentur, ‘MiSpeL Hintergrundpapier’, background paper, 1 October 2026
- Federal Ministry of Justice, ‘Erneuerbare-Energien-Gesetz (EEG 2023), § 19 Zahlungsanspruch’, gesetze-im-internet.de, accessed 6 October 2026
