Balancing group (Bilanzkreis) · Glossary

A balancing group is a computational settlement unit of the electricity market. It combines feed-in and withdrawal points as well as trading transactions and assigns them to a responsible market participant. The German Energy Industry Act (Energiewirtschaftsgesetz) defines the balancing group in the electricity sector as a combination of feed-in and withdrawal points within a control area. It is intended to reduce deviations between feed-in and withdrawal through pooling effects and to enable trading transactions. A balancing group is therefore not a line and not a grid of its own. Nor does it describe a physical flow of electricity. It is better understood as an account for energy quantities: for each quarter-hour, it records what was planned, what was actually fed in or withdrawn, and who is responsible for the difference.

Why balancing groups exist

In the power grid, generation and consumption must be physically in balance at all times. The market, by contrast, works with forecasts, supply contracts and trading transactions. These constantly deviate from reality, for example because of weather, consumption behaviour or power plant outages. The balancing group system makes these deviations economically attributable to individual participants. In short: the transmission system operators ensure physical stability, but the costs of deviations are meant to be borne by those whose portfolios cause them. The Energy Industry Act therefore expressly attributes a central importance to the balancing group and balancing energy system for security of supply.

Structure and allocation

The rules originally stem from Section 4 of the Electricity Grid Access Ordinance (Stromnetzzugangsverordnung, StromNZV). Accordingly, grid users form balancing groups within a control area in each case. Each balancing group must contain at least one feed-in or withdrawal point. For pure trading transactions without supplying final consumers, however, balancing groups without such points are also possible. A balancing group may also be assigned to another balancing group as a sub-balancing group. Every feed-in and withdrawal point must be assigned to a balancing group. This makes it possible to attribute every quantity of electricity actually measured to a responsible party.

An important correction to a common simplification follows from this: a balancing group does not extend arbitrarily across control area boundaries. Germany has four control areas, operated by 50Hertz, Amprion, TenneT and TransnetBW. A supplier with customers in several control areas therefore maintains separate balancing groups in each of these areas. Energy quantities between balancing groups are shifted by means of schedules. Irrespective of this, the physical flow of electricity does not follow the contractual allocation. Electricity from a particular wind farm does not flow specifically to a particular customer merely because both are assigned to the same participant for balancing purposes.

The balance responsible party

For each balancing group, a balance responsible party (Bilanzkreisverantwortlicher, BKV) must be designated to the competent transmission system operator. The BKV is responsible for a balanced position between feed-in and withdrawal in every quarter-hour. As the interface between grid users and transmission system operators, the BKV bears economic responsibility for deviations. BKVs are typically energy suppliers, traders, direct marketers, large industrial companies or service providers. They do not need a power plant of their own. Their tasks include consumption and generation forecasts, procurement on the forward, day-ahead and intraday market, and the submission of schedules.

What matters are energy quantities per quarter-hour, expressed in kilowatt-hours or megawatt-hours. Instantaneous power does not count here. A schedule specifies which energy quantities are delivered between balancing groups in which quarter-hour. Under the rules applied so far, schedules must be complete and must allow a balanced position of the balancing group. In this way they also contribute to a balanced position of the control area.

Balanced management – an obligation, not a recommendation

It is often said that balancing groups may simply deviate because deviations are settled anyway. This is not correct. Legally, the BKV is obliged to manage its balancing group in a balanced manner in every quarter-hour. Deviations that arise despite careful forecasting and trading are practically unavoidable and are settled. This does not make them a permitted option. The Bundesnetzagentur has expressly designed the balancing energy price so that it creates incentives for balancing group compliance. For example, it should not be worthwhile to deliberately speculate on balancing energy instead of readjusting on the intraday market. The expectation is therefore: forecast, trade and balance to the best of one's knowledge. Exact hits are not required, but deliberate imbalances are impermissible.

Balancing energy, control energy and reBAP

Transmission system operators deploy control energy to offset power imbalances in the control area and keep the frequency stable. Balancing energy, by contrast, describes the perspective of the individual balancing group. It refers to the energy quantity with which the transmission system operator computationally offsets and settles the deviation between plan and actual of a balancing group. If a balancing group draws more than it has covered, it is short. If it feeds in more or withdraws less than planned, it is long. Both terms are closely connected: the costs of the control energy deployed flow into the price of balancing energy.

In Germany, balancing energy is settled in quarter-hour intervals at the uniform cross-control-area balancing energy price (regelzonenübergreifender einheitlicher Bilanzausgleichsenergiepreis, reBAP). Since 2010 it has applied uniformly in all German control areas because of the grid control cooperation (Netzregelverbund) of the four transmission system operators. For each quarter-hour, the reBAP results from the costs and revenues of the activated control reserve and the balance of the grid control cooperation. It generally applies symmetrically to long and short balancing groups. It can be positive or negative, so that, depending on the situation, the direction of payment may also reverse. Further components, such as a link to intraday exchange prices and a scarcity component, are intended to prevent balancing energy from being cheaper than closing out a position on the market. When the capacity reserve is called upon, the price can exceptionally become asymmetric. If the overall system is almost balanced, small balances in the denominator of the calculation can lead to very high individual prices.

Renewables, consumers and grid operator balancing groups

As the share of wind and solar power grows, managing balancing groups becomes more demanding. Feed-in can be forecast well, but never completely. Direct marketers and suppliers therefore update their forecasts continuously and offset forecast errors on the intraday market until shortly before delivery. Grid operators also maintain their own balancing groups. These include a balancing group for electricity under the Renewable Energy Sources Act and a separate balancing group for the balancing settlement of system security measures such as redispatch.

On the consumption side, many households are still balanced using a standard load profile. In this case, consumption is not measured in every quarter-hour; instead, a typical profile is assumed. With heat pumps, electric cars, battery storage, dynamic tariffs and smart metering systems, the actual time of consumption becomes more important. Suppliers then have to procure not only annual quantities but also manage the time distribution of consumption.

Distinctions and limits of the term

Balancing group and supply contract: The supply contract governs who supplies a customer and on what terms. The balancing group assigns the resulting quantities to a responsible party.
Balancing group and green electricity: A green electricity tariff does not mean that only green electricity physically flows to the socket. Origin is evidenced through guarantees of origin and contractual rules, not by the balancing group alone.
Balancing group and security of supply: Balancing group compliance relieves ongoing system operation and limits the need for control energy. However, the balancing group does not answer whether sufficient firm capacity or adequate grids are available. These questions of security of supply lie at other levels.

Behind the balancing group there is also extensive market communication. Meter values, allocations, schedules and settlement data are exchanged between suppliers, grid operators, metering point operators and transmission system operators. If data arrive late or are erroneous, it becomes unclear to whom which quantities and costs are to be attributed.

Legal status in Germany

The definition remains unchanged in Section 3 of the Energy Industry Act (EnWG); in the current version on gesetze-im-internet.de it is number 21. According to the Bundesnetzagentur, the StromNZV expired at the end of 31 December 2025. Its contents are being transferred into topic-specific determinations of the Bundesnetzagentur. In the GPKE determination BK6-22-024, the chapter "Bilanzkreise" (balancing groups) corresponds verbatim to the former Section 4 StromNZV. The grid operator balancing groups have also been transferred there. The principles described thus continue to apply in substance, now on the basis of these determinations as well as the balancing group contracts and the market rules for balancing group settlement (MaBiS).

Sources

§ 3 EnWG – Begriffsbestimmungen — Bundesministerium der Justiz / gesetze-im-internet.de; unbekannt (aktuelle Fassung). § 3 Nr. 21 EnWG (Bilanzkreis); laut Gesetzesfassungen im Suchergebnis zudem § 1a Abs. 2 EnWG
§ 4 StromNZV – Bilanzkreise — buzer.de (Wiedergabe des Verordnungstextes); unbekannt. § 4 Abs. 1 bis 3 StromNZV
Beschluss BK6-22-024 (Festlegung zur Anpassung der GPKE u. a.) — Bundesnetzagentur, Beschlusskammer 6; 2024-03-21. Begründung, Kapitel zu Bilanzkreisen und Netzbetreiberbilanzkreisen
Ausgleichsenergiepreis — Netztransparenz.de (deutsche Übertragungsnetzbetreiber); unbekannt. Abschnitt Allgemeine Informationen & Historie des Ausgleichsenergiepreises
Ausgleichsenergieabrechnung gegenüber Bilanzkreisverantwortlichen — Amprion GmbH; unbekannt. Seitentext zu reBAP und Netzregelverbund

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Edited by eCMS on 11.11.2026 15:45