The energy transition has picked up speed. Wind energy is now the most important source of electricity in this country. Their share was 25.6 percent for the first time last year. According to a survey by the Federal Statistical Office, for the first time more electricity from wind turbines was fed into the domestic grid than from coal-fired power plants. The proportion is likely to rise further after the federal government created the legal basis for the further expansion of offshore wind energy last week. According to the German Wind Energy Association, more turbines are being built on land after the expansion stalled between 2018 and 2020. So fresh wind power will soon be blowing into the grids again.
But will it be possible to capture enough moving air to be able to do without coal-fired power plants entirely by 2038, as the federal government's most recent climate targets envisage?
After all, it's about 40 gigawatts in Germany.
A current study from Jena in the
Meteorological Journal
gives hope.
According to this, a fraction of the available wind is sufficient to cover several times the energy demand forecast worldwide up to 2050 - at least in theory.
A windy affair
Axel Kleidon from the Max Planck Institute for Biogeochemistry used a simple thermodynamic model to calculate that wind turbines close to the ground could extract around 0.5 watts per square meter of the atmosphere and convert them into electrical power. Converted to the earth's surface (usable for wind generators) that is theoretically around 250 terawatts of wind power. However, this is still a long way off. In order to achieve the maximum possible yield, the wind farms should not be built too close to each other, warns Kleidon. Because on the leeward side, the wind speed is often so reduced that the yield of neighboring wind turbines is reduced.
The question of where the electricity comes from on days when there is no wind remains unanswered - or when the wind is too strong, which forces the wind turbines to shut down. The expansion of the grid is stalling, and there are still no high-performance energy storage systems that can hold wind power for a longer period of time. In terms of security of supply, renewables are therefore still a bit of a windy affair for many observers.