The redispatch procedure was originally only applicable to power generators or photovoltaic system operators with an output of 10 MWp or higher, and in October 2021 became the so-called. Redispatch 2.0 extended and has since applied to all plants with a size of 100 kWp or more. It is a procedure for controlling and coordinating power grids. It is intended to ensure that the feeding and withdrawal of electricity in the grid are always in balance. Redispatch 2.0 is intended to prevent power outages and applies to all power plant operators. The operation of all power plants is planned anew on a regional, temporal, and gradual basis in the so-called German federal dispatch – a kind of timetable – from day to day. Redispatch 2.0 only intervenes when power lines are overloaded due to grid bottlenecks. In this case, grid operators can ask certain generation or consumption units to change their electricity production or consumption in order to reduce the overload on the grid. The affected plant operators receive compensation for this. They receive this either directly from the grid operators or indirectly from the respective direct marketers.
Goal of the Redispatch 2.0 procedure: Faster expansion of energy lines
The Redispatch 2.0 procedure is part of the law to accelerate the expansion of energy grids.EnlagIt is intended to help accelerate the expansion of power grids and thus support the energy transition in Germany. The German transmission system operators (TSOs) use the mechanism. It refers to the Ordinance on Measures for Grid and System Security in the Electricity Grid (Measures Ordinance Electricity 2020 - MaßnVStrom 2020) of the Federal Ministry for Economic Affairs and Energy. It stipulates that TSOs can oblige certain plants in the grid to feed in or reduce electricity as needed. These plants are referred to as redispatch plants.
Effectively plan and manage consumption and generation
Specifically, this means that transmission system operators plan the deployment of all electricity generators on a day-to-day basis based on consumption and generation forecasts. This is intended to ensure a stable electricity supply for all regions in Germany. They can initiate the Redispatch 2.0 procedure if the power grid is affected, for example, by a defective power line, a complete failure of a power generation plant, or by fluctuations in volatile energy sources such as wind power and solar energy. In such cases, transmission system operators can activate certain redispatch plants to maintain the power supply or deactivate them to relieve the grid. The costs for redispatch measures are passed on to the operators of the redispatch plants. For example, if electricity generation from wind turbines or photovoltaic systems is higher than the electricity demand, the Redispatch 2.0 procedure helps. In this case, the surplus electricity is either integrated into the grid, or electricity generation from other sources is reduced.
Technical requirements for participating in Redispatch 2.0
Technically, PV systems from 100 kWp are connected via an interface to an easy-to-install radio control receiver and linked to the redispatch process. The device receives commands via a radio signal from a central control system, which can increase or decrease the output of the generating plant. The data basis is formed by the values that are continuously transmitted by a smart meter. Both devices are usually also installed in the Rooftop photovoltaic systems, at Solar parks and Solar Carports. They can be retrofitted to existing systems if necessary.
Further processing of the collected data
All data from all power plants is received by the transmission system operator, who performs a new grid load calculation daily to keep short-term redispatches as low as possible. Their work has naturally increased significantly with the expansion of Redispatch 2.0. The costs of these measures have also risen considerably. In Germany as a whole, these reached a record level of 612 million euros as early as 2021. One reason for this was likely also the development of new balancing, billing, and call-off models.
Criticism of Redispatch 2.0
The entire Redispatch 2.0 process between plant operators, direct marketers, and grid operators has not yet been finalized since its introduction in October 2021. So far, for example, the balancing responsible parties (BRPs) coordinate the financial compensation of grid operators. There is no automatic balance settlement yet. This is due to a lack of data and interface standards and causes additional costs, as the BRP has to manually buy or sell electricity quantities. This bottleneck also means that plant operators have to wait longer for their remuneration, and errors creep into the calculations.
Currently, photovoltaic system operators generally cannot provide a definitive forecast of the electricity they will generate in the future, and therefore can only plan the feed-in or purchase quantities very poorly in advance. As a result, individual reconciliations are still created every time redispatch interventions occur. This enormous additional effort is increasingly met with a lack of understanding not only by the balance group coordinators but also by direct marketers. They too can only pay out compensation to the system operators with a delay, using a blended price that, in case of doubt, is below the market value.
The expansion of the power grid must be urgently pushed forward. Redispatch 2.0 can only accelerate this process if it is clearly regulated itself and thus replaces the current complex interim solution.