system deviation

any excess or lack of electricity in the power grid calculated every quarter-hour. Deviations occur when there is a difference between the actual amount of electricity consumed and the total amount of electricity planned. Each settlement entity creates a plan for the consumption and production of electricity by its balancing group one day in advance and is responsible for any deviations which are the result of faulty planning. System deviation for each trading quarter is calculated as the combined deviations of all settlement entities. System bias can be positive or negative. It is positive if the total consumption in the system is lower than agreed, or the planned amount of all settlement entities, resulting in a surplus of electricity in the power grid. On the contrary, if total consumption is higher than planned and there is a shortage of electricity in the power grid, the bias is negative.