|Activation Optimisation Function (AOF)|
|European Union Electricity Market Glossary|
Rules on the activation optimisation function are stipulated in Article 31 of the Commission Regulation (EU) 2017/2195 of 23 November 2017 establishing a guideline on electricity balancing - see box.
The activation optimisation function is central to the process of the activation of balancing energy.
In order to enable the cross-border exchange of balancing energy, the activation of balancing energy has to be coordinated by a common function.
This function, known as the activation optimisation function, determines the most efficient activation of the incoming balancing request while respecting some capacity and operational restrictions.
The activation optimisation function is responsible for using the algorithm which is commonly developed by the Transmission System Operators (TSOs).
The activation itself is done by the controlling units of the respective TSOs. This activation is automatically done for Frequency Restoration Reserve (FRR) automatic or manually done for both FRR manual and Replacement Reserve (RR).
In order to implement this activation process robust communication procedures are required between the common function and the controlling units/operators.
The steps involved in the activation of balancing energy are as follows:
1. the requesting TSOs send their requirements to the Activation Optimisation Function;
2. after the balancing energy gate closure time, the activation optimisation function calculates the most efficient activation taking the following into account:
(a) common merit order list (CMOL) containing all balancing energy bids,
(b) available cross zonal capacity either available after Intraday or reserved previously,
(c) network stability constraints,
(d) balancing requirements of the TSOs,
(e) imbalance netting potential;
3. activation optimisation function sends the individual activation amounts (as a correction signal) to each responsible TSO (connecting TSO);
4. the connecting TSO activates the successful balancing energy bids (via a phone call or automatically by activation system such as a MOL-Server or local controller);
5. balancing energy is exchanged through commercial schedules or virtual tie-lines;
6. balancing energy is settled between the providers and the TSOs involved.
According to Article 29(6) of the said Regulation (EU) 2017/2195 of 23 November 2017 the request for activation of a balancing energy bid from the activation optimisation function shall oblige the requesting TSO and connecting TSO to accept the firm exchange of balancing energy.
Each connecting TSO shall ensure the activation of the balancing energy bid selected by the activation optimisation function.
The balancing energy shall be settled between the connecting TSO and the balancing service provider (BSP).
Moreover, the said Regulation 2017/2195 in Article 29(7) and (9) stipulates that the activation of balancing energy bids is to be based on a TSO-TSO model with a common merit order list.
Each connecting TSO shall submit, prior to the TSO energy bid submission gate closure time, all balancing energy bids received from balancing service providers to the activation optimisation function.
The connecting TSOs shall not modify or withhold balancing energy bids, except for:
Pursuant to Article 29(14) of the said Commission Regulation (EU) 2017/2195 of 23 November 2017 each TSO may declare the balancing energy bids submitted to the activation optimisation function unavailable for the activation by other TSOs because they are restricted due to internal congestion or due to operational security constraints within the connecting TSO scheduling area.
Article 31(3) of the said Commission Regulation (EU) 2017/2195 stipulates that each activation optimisation function must use at least one common merit order list for upward balancing energy bids and one common merit order list for downward balancing energy bids.
Article 31(6) - (8) of the said Commission Regulation (EU) 2017/2195 envisions the following procedure in that regard:
- each TSO shall submit its activation requests for balancing energy bids to the activation optimisation function,
Network Code on Electricity Balancing (Commission Regulation (EU) 2017/2195 of 23 November 2017 establishing a guideline on electricity balancing - NC EB), Article 2(39), Article 29(6), (7), (9) and (14), Article 31
|Last Updated on Thursday, 15 March 2018 10:16|