How is it decided which plants produce our electricity at any given time of the day?
The schedule of plants selected to run is determined every day and 24 hours in advance to meet the forecast electricity demand. However, it is adjusted in real time in response to unforeseen events such as electrical faults or plant breakdowns 1. While the final determinant of whether a plant will run or not will often be the price of its power, its location has to be taken into account as congestion can arise on the grid with serious consequences for the management of the power system. Certain generators, such as renewables, get priority dispatch as required by EU law.