Neckarwestheim nuclear power plant (shortly before shutdown in April): Electricity imports reduce wholesale prices in Germany, according to the network agency
Dirk Sattler / IMAGO
After the shutdown of the last German nuclear power plants, the Federal Network Agency is defending itself against accusations that the Federal Republic would now mainly buy nuclear and coal-fired electricity from abroad. "It can be cheaper to import electricity than to produce it more expensively in our country," says Klaus Müller, President of the Authority. In foreign trade, however, it depends on which power plants can deliver the cheapest at the respective hour. "And these are almost always renewables," says Müller. "Also from France, from where, among other things, cheap solar power has recently come to us." The imports would thus lower wholesale prices in Germany.
According to the Network Agency, Germany purchased a net 3.5 terawatt hours of electricity from abroad in May; this is the sum of imports minus exports. This means that in the same month, the Federal Republic of Germany covered a good nine percent of its electricity consumption with foreign aid. The import balance was thus significantly higher than in previous years. Imports remained at a high level in the first half of June.
Cross-border transport limited
According to the Agora Energiewende think tank, 52 percent of the electricity imported in May was renewable energy, 23 percent nuclear and seven percent coal-fired. The remaining percentages come from electricity from gas-fired power plants, pumped storage facilities and other energy sources. The most important reference country was France, followed by Denmark and Switzerland. Green electricity generation in Europe is currently benefiting, among other things, from the heavy rainfall in the first quarter; these are now increasing the yield of hydropower, for example in Norway and Switzerland.
In order to determine the generation mix of imports, Agora used the electricity mix in all countries that have cross-border lines to Germany – but only in the hours in which electricity actually flowed into the Federal Republic. According to the experts, Germany could have imported even more electricity in some hours if the cross-border lines had a higher capacity.
With the nuclear phase-out on 15 April, the three power plants in this country that – after renewable energies – had the lowest marginal costs went off the grid. Marginal cost is the price of an additional megawatt hour generated. The loss of nuclear power is now partly offset by lower consumption, and partly by additional generation by new renewable energy plants, says Philipp Godron of Agora Energiewende. "Germany can compensate for the rest either with gas and coal-fired power plants at home or with imports." In this trade-off, renewables have the lower marginal cost; they thus prevent higher utilization of gas and coal-fired reactors. In a country like Poland, whose own generation mix is still heavily influenced by coal, Agora is also currently observing brisk electricity imports.
Even though the level of imports this spring stands out, the Federal Republic of Germany already had a noticeable need for imports in the months of May and June in previous years. "That's because we've historically expanded more wind power than solar plants," Godron explains, "and wind production is stronger in the winter months."
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According to experts, however, the supply of green electricity from neighbouring countries should not prevent Germany from expanding renewable energies domestically. The restructuring of the electricity system is taking place simultaneously in many European countries. "No country is pursuing the strategy of generating excessive amounts of electricity and exporting as much as possible," Godron warns. If, for example, wind fronts move through Europe from west to east, the electricity yield is ideal if wind power is expanded in all regions. On top of that, the demand for electricity is increasing, for example with the switch to heat pumps and electric cars. "More renewable generation also makes Germany more independent and resilient to sharp increases in the price of energy imports, as we saw last year with gas," Godron argues.
If, on the other hand, the idea of a self-sufficient power supply were to be implemented, this would be very expensive, according to Godron. The Federal Republic of Germany would then need much more storage capacity at home.