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Dark times: Whether the lights go out in winter also depends on the continued operation of the remaining nuclear power plants
Photo: Stefan M. Prager / IMAGO
Cities and municipalities are drawing up blackout plans, companies are upgrading their emergency power supply – Germany is preparing for a winter of power outages.
Because the gas crisis is developing into an electricity crisis.
With the Russian gas supply ban, the idle nuclear power plants in France and the drought in Europe, a dangerous situation has brewed on the electricity market.
One thing is certain: the power supply is getting tight.
In view of the worsening of the energy crisis, warnings of widespread power failures in Germany are increasing.
"There is a risk of a blackout," the Association of Towns and Municipalities recently warned.
Similar voices came from energy companies.
If, in addition to industry and charging stations, thousands of fan heaters were also connected to the grid in winter, things could become critical at the local level, said
Frank Mastiaux
(58), head of the energy supplier EnBW in an interview with manager magazin.
A power grid stress test by the federal government and power grid operators has now also shown that "crises by the hour in the power system in the winter of 22/23 are very unlikely, but cannot be completely ruled out at the moment".
So are the lights really going out in this country soon?
Amprion prepares for shutdowns
Yes, that can happen.
According to Amprion, one of four transmission system operators in Germany, there is a risk of power failures.
This winter, for example, the grid operator could have to turn off electricity to consumers for the first time.
It is likely to be a matter of hours and not days, says
Solveig Wright
, Amprion's spokeswoman.
But what is not to be expected is a real blackout, i.e. an uncontrolled collapse of the European electricity system, as the operator defines it.
"Under the current framework conditions, we do not expect a blackout."
Shutdowns are imminent, but they don't happen easily either.
In order to understand what this means, one has to consider how the transmission system operator normally keeps the power supply stable and what measures it takes before an emergency occurs.
In Germany, the transmission system operators – these are Amprion, TransnetBW, TenneT TSO and 50Hertz – are responsible for the power grid for national supply and transmission in the high-voltage range.
Their task is to operate, maintain and optimize, strengthen and expand a "safe, reliable and efficient energy supply network without discrimination", according to the Energy Industry Act.
Ensuring the security of the power supply is therefore their statutory mandate.
The electricity from large producers such as power plants and offshore wind farms travels over long distances to the distribution grids and thus to where it is needed via their grids.
They collect network fees for this.
Balancing energy as the first means
One of the first measures that the network operator uses to avoid fluctuations in the network frequency is the use of so-called balancing energy.
In this way, Amprion compensates for any discrepancies between the expected and actual electricity conditions at short notice.
Because for grid stability, as much must always be fed into the grid as is consumed.
At 50 Hertz, the power grid is in balance.
In order to achieve the frequency, the network operators constantly make calculations.
If the wind is weaker than expected, a turbine in a power plant fails, or some other unexpected event occurs, deviations occur.
Because less is being fed in than forecast.
In this case, the control energy kicks in.
The same applies if consumption differs.
"The electricity feed-in from generators or storage facilities is then increased or reduced - partly automatically, or manually if the lead time is longer," says Wright.
"This is not an emergency, but normal everyday business."
In the case of balancing energy, the electricity comes not only from power plants, but also from battery storage or wind farms.
Emergency power plants are ready
In critical situations such as power shortages, the power grid operator can also use its capacity reserve.
An instrument introduced especially for the winter, when consumption is higher and the demand for electricity cannot be met from the market.
For this emergency, power plants are available, which are ramped up in such a scenario.
"They have never been retrieved. The case has not yet occurred," says Amprion spokeswoman Wright.
Last resort: controlled shutdowns
Only as a last resort, i.e. when all reserves have been exhausted, does the transmission system operator switch off consumers in a controlled manner.
This can currently be observed in California.
The US state recently asked owners of electric cars to postpone charging due to a power shortage.
The idea behind the shutdowns is simple: if there is not enough electricity, consumption must decrease.
Since the shutdown is "non-discriminatory" at every network level, as Amprion says, it can potentially affect anyone.
"In the event of a shutdown due to insufficient load, parts of the country across Germany go dark," explains Wright.
You can imagine this as if there were black spots everywhere.
In this scenario, each network operator in Germany would shed the load proportionately according to a defined key.
The situation is different in the case of controlled shutdowns due to a grid bottleneck.
In contrast to a power shortage, only individual regions would be affected in this case.
Many imponderables decide
How likely such a shutdown is is difficult to say and depends on many factors.
One of them is how warm or cold the winter will be.
Another: how quickly Berlin and the operators manage to make the necessary preparations together.
Because in order to avoid controlled shutdowns, work is currently being carried out on a whole series of measures that the transmission system operators proposed as part of the most recent stress test.
They recommend "exploiting every opportunity to increase power generation."
A decisive factor is therefore whether the decommissioned coal-fired power plants can be connected to the grid again in good time.
With regard to the three remaining nuclear power plants, the transmission system operators are demanding so-called stretch operation.
The supply of the power plants with raw materials must also be secured.
The prioritization of energy transport in rail traffic, for example, has already started after low water restricted the supply.
At the same time, Amprion and its three competitors are demanding incentives for companies from the government so that industrial companies in particular can reduce their electricity consumption in critical phases.
All in all, the measures are not only aimed at ensuring that there is enough electricity, but also that it gets to where it is needed.
According to Amprion, binding agreements with neighboring countries on so-called redispatch services are therefore also important.
This means that if the grids are so overloaded that there is a grid bottleneck, generation must be reduced on one side of the line and increased on the other.
This requires available power plant capacity, according to Amprion's analysis, if in doubt also from abroad.
The company is currently trying to contractually secure this.
In all scenarios that Amprion has outlined with its three competitors, the "supply situation in the coming winter half-year is extremely tense".