13. Grid stability (Storing energy for a stable supply)
Energy must be generated in the same amount as what is being used at any time. If not, current fluctuations can cause the power grid to collapse. But power consumption varies a lot depending on the time of the day, and so does the power feed into the grid from renewable energy sources, such as sun and wind. On rainy days, photovoltaics only generate a small amount of power. And depending on the weather, there might be hardly any wind for days.
Challenge: dark calm
The solution: When plenty of power is generated, it must be converted into other forms of energy that can be stored. During peak demands, this energy must be converted back to electrical power and fed into the power grid. Because we need a stable grid, even during a dark calm winter’s night…