Short Term Adequacy
Watch the video above for a basic explanation of the service (provided by ENTSO-E and Coreso).
Purpose
In every moment, production and consumption of energy must be in balance. This means that electricity must be generated at the exact moment when it is needed. This is due to the – by nature – lack of storage facilities for electricity. To secure the supply of energy, Nordic RCC investigates if the reliable available production capacity can meet the consumption at any given time, while also considering that there might be restrictions in the transportation of electricity to the place of consumption. If there is not enough reliable available production capacity to meet the consumption, measures need to be taken to avoid an adequacy situation.
Process
The Short Term Adequacy (STA) assessment performs the analysis if there is sufficient reliable available production capacity to meet the consumption, given the transmission capacity constraints in the grid. This assessment is done daily for the next 7 days’ time frame and provides the TSOs with an STA forecast.
The forecasts for the production, consumption and the transmission capacities in the grid are delivered by the TSOs.
A part of the consumption (the private households) and some of the renewable production systems (e.g. wind and solar) are weather dependent in the short term. Thereby the uncertainty of the forecasts decreases the closer to the operational day.
The production possibilities of some of the renewables, e.g. the hydro power plants with big water reserves, can depend on the weather situations during the past year. If it has been a dry period, the reservoir capacity can be low in a country or part of a country.
One of the inputs to the adequacy assessment is the capacities in the grid, and the STA assessment is thereby connected to the Outage Planning Coordination (OPC) service and the planned availability of the grid. This cross-service dependency is incorporated into the STA service.
The Short Term Adequacy is done on a regional level in the Nordic region, on a daily basis for the next 7 days as well as on a weekly basis, in a joint Nordic meeting with participants from the TSOs' operational staff and Nordic RCC. It considers the expected outage situation, adequacy situation and expected operational situation for the next week.
On a European level, the Short Term Adequacy assessment is done on a daily basis as well as for the next 7 days. If any adequacy issues are seen, procedures to coordinate and, if possible, reduce the consequences of the lack of adequacy exist.
The STA service is described in SOGL* art 81 and art 104-107.
*SOGL: System Operation Guideline