Share of renewables in the east at almost 75 percent

The share of renewable energies in electricity consumption in the eastern and northern German states remained stable at just under 75 percent last year. A prolonged dark doldrums in the final months of 2024 ensured that the share did not rise more sharply, said Stefan Kapferer, head of the eastern and northern German transmission system operator 50Hertz. Nevertheless, renewable electricity was even able to cover around 100 percent of demand on around 80 days a year.

The term "dark doldrums" is used when the sun barely shines and at the same time there is little or no wind. This means that solar systems and wind turbines can only generate a small amount of electricity. The opposite is the "light breeze", i.e. lots of sunshine and wind at the same time, which can lead to an oversupply of electricity. There is no precise definition of "dark doldrums".

However, while the share of renewable energies continues to increase, the demand for electricity has been stagnating for years. According to the company, consumption in the 50Hertz grid area - in all eastern German states and Hamburg - was around 94 terawatt hours last year, the lowest it has been for 20 years. This is mainly due to the slow ramp-up of electromobility and the low demand for electricity-powered heat pumps.

Kapferer: Need more flexibility in the system

Even now, there is more renewable electricity in the grid on more and more days than is actually needed, said Kapferer. The longstanding focus on the rapid expansion of generation capacities must therefore change. "The message is clear: we don't need another four gigawatts of solar capacity every year at the moment, we need more flexibility in the system," he emphasized. "And we need the ability to transport the electricity through expanded grids."

50Hertz therefore plans to invest almost 23 billion euros in grid expansion by 2028. This is around five times as much as in the previous five-year planning period. 50Hertz is part of the Elia Group, a Belgian transmission system operator. The investor intends to support the investments with additional equity of around 2.2 billion euros. Around 850 million euros of this is to come from four private investors, including the infrastructure fund Atlas Infrastructure and the investment group BlackRock.