How is the energy of wind turbines stored and how are differences in wind strength compensated for?

Answer

The energy generated by the wind turbines is not stored, but immediately consumed by consumers on the other side of the grid. This is a property of the electrical distribution network. Production and consumption must be equal at all times, otherwise problems will arise.

Storing large amounts of electrical energy is a difficult problem for which no good solution exists today. In Belgium there is such a thing as the water basin of Coo, where water is pumped up at night, to let it flow back down during the day (hydropower). This is a form of energy storage, but the efficiency is not great.

The power that a windmill collects can be regulated: the angle of the blades is adjustable. If the wind suddenly drops, the available power of the wind turbine will of course also drop. This means that the electrical power must then come from somewhere else. For example, peak power plants can be used for this purpose, these are power plants whose power output can be changed quickly (typically gas turbines). This does not immediately cause major problems, because the share of wind turbine energy is relatively small in the total energy production. In Belgium, the lion’s share of electricity is still produced with nuclear energy.

Solar electricity, by the way, has the same problem. If in the future the majority of energy production will come from such sources, there will still be major challenges to build a distribution network that can cope with this (smart grid).