The grid needs the supply and demand to be balanced for the power to be stable. Otherwise you get fluctuations in voltage and frequency which are both bad for anything connected to the grid.
There can absolutely be an oversupply of energy. We need to either find ways to store that surplus energy, or use it for something positive like desalination or carbon capture.
But how is it fair for so many of his trials and investigations to drag on for 4 years, especially when the accusations are this serious?