BONN/BERLIN (dpa-AFX) - How can many heat pumps and private charging stations already be integrated into the local power grid without it collapsing? By allowing grid operators to dim the power consumption of these devices in an emergency, says the Federal Network Agency. On Monday, after a year-long coordination process, it published the rules according to which this should happen and how consumers will benefit.

Rules are intended to ensure security of supply

The agency describes the problem as follows: The majority of local electricity distribution grids are not yet designed for a rapid ramp-up of heat pumps and private charging facilities for e-cars. The grids therefore need to be digitized and expanded quickly. In the meantime, the regulations should ensure that the transport and heating transition is accelerated and that security of supply is also ensured in the so-called low voltage, says the authority.

The most important thing: in future, electricity grid operators will be allowed to temporarily restrict the power supply of newly installed, controllable heat pumps, charging stations or air conditioning systems in accordance with fixed rules if there is a risk of overloading the electricity grid. "A minimum output must always be available so that heat pumps can be operated and electric cars can continue to be charged," it said.

Grid operators may throttle - household electricity not affected

The distribution grid operators are allowed to reduce the consumption of the so-called consumption devices to up to 4.2 kilowatts for the duration of the overload. "This means that heat pumps can continue to operate and electric cars can usually be recharged for 50 kilometers in two hours." Regular household electricity is not affected by this, the authority emphasized. The requirements of large heat pumps with their higher electricity consumption would be taken into account.

Consumers can decide how the grid operator should intervene: either they allow the grid operator to control individual systems directly - or they select a maximum output value for several systems, which must not be exceeded overall in an emergency. In this case, the consumers would coordinate the reduction independently using an energy management system. Self-generated energy could be included in the calculation. A wallbox - i.e. a domestic charging station for an electric car - can then draw more electricity if it comes from its own solar system, for example.

Operators receive a reduction in the grid fee

In return, the operators of the controllable devices, such as households, will receive a reduction - either as an annual flat rate for the grid fee or as a 60% reduction in the grid fee working price for the respective devices.

Those who opt for the flat rate can also opt for a grid fee that is staggered according to the time of day from 2025. Consumers will then pay a lower grid fee when using electricity at times of low grid utilization.

In future, the grid operator will no longer be allowed to refuse or delay the connection of new heat pumps or private charging facilities and justify this with a possible local grid overload. "If bottlenecks occur, the grid must be expanded. We will pay attention to this," says authority president Klaus Müller.

In the event of a bottleneck, the grid operators are also not allowed to simply control and dim the systems on suspicion, but must first determine the exact grid utilization based on real-time measured values.

Grid operators must publish interventions

But how often does this happen? The Federal Network Agency assumes that grid operators will only have to intervene in exceptional cases and without any significant loss of comfort. "Complete shutdowns of controllable consumption devices are no longer permitted," it said. The grid operators must also publish such control interventions on joint internet platforms. This would also make it clear to the general public if overload problems occur in individual grid areas and the grid operator needs to better equip its grid.

The new rules will apply from January. There are long-term transitional arrangements for existing plants that already have an agreement for control by the grid operator. Existing systems without such an agreement remain permanently exempt, but can participate voluntarily. Night storage heaters will not be permanently subject to the new rules.

Grid giant Eon wants to limit control interventions to the minimum

Germany's largest distribution network operator Eon welcomed the new regulations. The regulations are an important emergency instrument for ensuring grid stability and are essential for the digitalization of the energy system. The aim is always to limit control interventions to the minimum. "Bottlenecks in low voltage are extremely rare," emphasized an Eon spokesperson.

Germany's third-largest distribution grid operator Netze BW was also positive. "Every operator can now start converting the grid accordingly," said Technical Managing Director Martin Konermann. "Wherever we already see a bottleneck, we will start to expand."

Associations rate regulations positively

The municipal utilities association VKU explained that the Federal Network Agency's decision supports the ramp-up of electromobility and heat pumps while also ensuring a stable grid. The increase in the previous minimum guaranteed output from 3.7 kilowatts to 4.2 kilowatts was viewed critically. The practicality of this output has yet to be proven.

The energy industry association BDEW spoke of a "good solution". This means that hundreds of thousands of heat pumps and wallboxes can now be connected quickly, said Kerstin Andreae, Chairwoman of the Executive Board of the German Association of Energy and Water Industries (BDEW). At the same time, this will ensure the usual high level of supply security in Germany./tob/DP/nas