Intra-day schedule modification according to the German electricity network access regulation (StromNZV) Concept for data exchange

Transcription

1 Intra-day schedule modification according to the German electricity network access regulation (StromNZV) Concept for data exchange Detailed concept for intra-day modifications

2 2 Working Group Detailed concept for intra-day modifications Andreas Benger Stefan Boerger Dirk Pooschke Dirk Rauschenbach Stephan Schlunke Jörg Wozny RWE Transportnetze Strom E.ON Netz GmbH E.ON Netz GmbH RWE Transportnetze Strom Vattenfall Europe Transmisson GmbH EnBW Transportnetze AG Contents: 1. Objectives General Conditions/Definitions Intra-Day modifications within the German market system Normal intra-day modifications Intra-day modifications due to a power plant failure Guidelines for the utilization of the Production failure message type Range of application Rules for the Implementation of Intra-day Modifications in Schedule Management Basic concept: cyclically automated control area matching Delimitation/Miscellaneous File format Schedule management process phases Intra-day schedule nomination Schedule nomination during the process phase: Day-ahead matching Schedule nomination in the intra-day process phase General Gate Closure Time Admissible frequency of schedule nominations Use of the Process Type element within an ESS Message Matching Confirmation Report/Anomaly Report Requirements Examples of Processing Faultless process flow Intra-day modification has not reached one of the parties addressed Faulty intra-day modification is not corrected by the balance responsible party Annex Rules for the utilization of the Process Type element Utilization of Imposed and Modified Time Series in an ESS Confirmation Report Imposed Time Series Confirmed Time Series with the Modified status Status in a Confirmation Report Glossary of terms... 15

3 1. Objectives Conceptual development/implementation of a schedule management scheme with a view to improving the efficiency of the transmission system operators (TSOs) schedule management systems to cope with the requirements resulting from the German electricity network access regulation (StromNZV) with regard to the possibilities of modifying cross-control-area schedule nominations. The concept pursues the following subordinate targets: 3 Adjustment of lead times for schedule modifications pursuant to Article 5 of the StromNZV. Minimum changes to the communication among balance responsible parties and TSOs. Fast coordination among TSOs of schedule nominations going beyond control area boundaries, and fast and complete provision of information to balance responsible parties about the status of schedule nomination. The process flow must be independent of the communication channel (Internet-Mail, ISDN-ftp) through which the data exchange is implemented. Independence from the data format as far as possible: Currently, apart from the ESS Version 2.3 [2], the Version 3.0 has also been released, and Version 3.1 is under discussion. A subsequent adjustment of the process to the superior ESS Version should involve as little expenditure as possible for all market participants. Integration of schedule modifications registered as a result of a power plant failure. It must be possible for TSOs to process schedule modifications attributable to a power plant failure as part of the automated process. Implementation must be finalized by the end of 2006.

4 4 2. General Conditions/Definitions 2.1 Intra-Day Modifications within the German Market System According to the Regulation on access to electricity supply networks ( Verordnung über den Zugang zu Elektrizitätsversorgungsnetzen - StromNZV) [7], a distinction is made between two kinds of possible intra-day modifications within the German market system: o Article 5, paragraph 2, 1st sentence : Cross-control-area schedules can be modified at every quarter of an hour of a day with an advance notice of at least three quarters of an hour. o Article 5, paragraph 4, sentences 1-3: The imbalance between feed-in and extractions attributable to forced power plant failures must be offset by the transmission system operator for four quarters of an hour including the quarter-hour during which the failure occurred. Concerning the period following these four quarters of an hour, the balance responsible party is required to offset the power loss. To this end, it can modify its schedules (contrary to [Article 5], paragraph 2, 1st sentence) with an advance notice of 15 minutes at the beginning of each quarter of an hour. Definition: Intra-day modifications are all cross-control-area changes to schedules arriving at the responsible TSO after the nomination deadline of the previous day. Concerning the lead times mentioned in the StromNZV and all other verifications carried out on that basis, the time of receipt (time stamp) of the file (ESS Message) by the TSO concerned and not the time of sending or generating this file by the sender shall be applicable Normal Intra-day Modifications Handling of normal intra-day modifications (StromNZV, Article 5, pragraph 2) requires that the matching process between the TSOs concerned be automated as far as possible. This process is described in Section 3 of this paper Intra-day Modifications due to a Power Plant Failure Matching of schedule modifications caused by a power plant failure, must be carried out in the most critical case within a minimum period of less than about 10 minutes (a system-immanent lead time of 5 minutes is required for the controllers). The distinction between schedule nominations due to a power plant failure and normal intra-day modifications is made through the message type: A new message type Z10 (production failure) is introduced for schedule nominations due to failure of a generating unit. In that case, this message type has to be carried in the file instead of the message type A01 (Balance responsible schedule) (see also explanations in Section 5.1). The matching processes subsequently carried out among the TSOs can then be based upon the same scheme as matching of normal intra-day modifications.

5 Guidelines for the utilization of the Production failure Message Type This particular message type is required only for the differentiation of admissible lead times. All other rules for schedule nominations are maintained: Information volume in the event of changes: The information content of a schedule message accepted by the TSO must not be reduced in the case of a change or cancellation. All time series submitted to and accepted by the TSO must be completely contained in additional schedule messages for the day in question. Cancellation of time series: If a time series submitted for a certain day is to be cancelled, all values need to be changed to 0 and carried until the end of the day concerned. Allocation of version numbers The version number starts at 1 every day. It is carried as Message Version and as Time Series Version. For every change that is made, the Message Version is increased by 1 and the change or new Time Series are marked with this new number. Example: Version No File Transaction A Transaction B Transaction C Initial registration Not existing Transaction B changes Not existing Transaction A changes Not existing New transaction C Figure 1: Versioning Message identification / Time series ID: IDs must not be changed as compared to the previous version. Message version: Versioning has to be made according to the ESS IG Version 2.3 [2] Section (see also: Figure 1) Schedule modifications attributable to a power plant failure are not separately versioned. 2.2 Range of application The methodology described is applied to all intra-day schedule nominations within and between the control areas of the following TSOs: EnBW Transportnetze, EON Netz, RWE Transportnetz Strom and VE Transmission.

6 6 3. Rules for the implementation of intra-day modifications in schedule management 3.1 Basic concept: cyclically automated control area matching Immediately after each quarter-of-an-hour turn, all intra-day schedule messages received by the TSOs until this turn are automatically coordinated among the latter. Immediately after the coordination, the result is automatically reported to the balance responsible parties concerned through an Intermediate Confirmation Report (CNF) and, in the case of any discrepancies, by an additional Anomaly Report (ANO). 3.2 Delimitation/Miscellaneous The agreements described below were made for the implementation of cyclically automated control area balancing. The information given in the follow-up points applies exclusively to across-controlarea (external) schedule modifications among the German TSOs, unless otherwise specified: 3.3 File format The format of files for schedule nominations of balance responsible parties to TSOs including intraday modifications, do not differ from schedule nominations transmitted by 2:30 p.m. the day before. They need to be complete (i e. include all schedules for the respective day). Versioning of message and time series comply with the current general German market rules and are consistent with the ETSO Scheduling System (ESS). Handling of an intra day schedule nomination as against a normal schedule nomination up to gate closure time (14.30hrs) of the previous day, depends exclusively on the time stamp of receipt by the recipient TSO. (see also definition in Section 2.1) 3.4 Schedule management process phases Concerning schedule message processing for a day D, the following basic phases need to be distinguished: Day ahead: previous month until D-1, 14.30hrs: No change as compared to current rules. Day-ahead matching from D-1, 14.30hrs to D-1, 18.00hrs: Particular characteristics are described in Section 3.5.1, Schedule nomination during the process phase: Day-ahead matching. Intra day: from D-1, 18.00hrs, to D, 24.00hrs: Start time for the automated intra-day matching process is normally D-1, 6 p.m. In exceptional cases, this start time can be postponed to a later date. In this case, the Day-ahead matching phase is extended. Further details are given in the following Sections of this Paper. Day after: from D+1, 00.00hrs to 16.00hrs of the working day following D: No change as compared to current rules. Hence follows that both the current and the following day are within the intra-day phase between 18.00hrs and 24.00hrs every day.

7 7 3.5 Intra-day schedule nomination Schedule nomination during the process phase: Day-ahead matching Formally correct schedule nominations with schedule modifications arriving between the end of the day-ahead phase (D-1, 14.30hrs) and the start time of the intra-day phase (D-1, 18.00hrs) are accepted by the recipient TSO until the start time of the Intra-day phase, but initially they are not further processed and matched. Only an informal acknowledgement of receipt in the form of a text file is sent to the balance responsible party. If the file contains formal errors, a formal negative acknowledgement report (ACK, with the reason code A02: Message fully rejected ) is immediately sent to the balance responsible party concerned. The formal inspection within this period is always carried on the basis of the schedule nominations received by the balance responsible party during the day-ahead phase and formally receipted by means of an ACK (rejected schedule nominations are also subject to this inspection) Intermediate Confirmation Reports (CNF) and Anomaly Reports (ANO) which the balance responsible party receives during this day-ahead matching phase or which it requested through a status request, are normally based on the last schedule message received until 14.30hrs which forms the basis for the TSOs matching for the following day within the UCTE power system and which was confirmed to the balance responsible party through an Acknowledgement Report (ACK) with the Reason Code A01. An exception to the above rule are subsequent nominations in conjunction with the day-aheadmatching for which the TSOs manually activate the further steps of processing which proceed automatically during the day-ahead phase and which are concluded by sending the Acknowledgement Report (ACK) and, where applicable, the Anomaly Report (ANO) to the balance responsible party. With the start of the intra-day phase, the last nomination from a respective balance responsible party that was received up to that time and receipted by a text file at the time of receipt, is taken over by the TSO into the matching process of the intra-day phase. The TSO shall transmit an Acknowledgement Report to the balance responsible party as part of the processing result Schedule nomination in the intra-day process phase General During the intra-day process phase, schedules can be registered at any time. The schedule nomination is immediately subjected to a formal inspection by the TSO and confirmed through an Acknowledgement Report, unless the quarter-hour matching process is in progress. In this case, the incoming schedule nomination of the balance responsible party concerned is postponed until the matching process is finalized. The formal inspection and the confirmation through an Acknowledgement Report take place immediately after finalization of the matching process as part of the schedule nomination processing result. If several schedule nominations of a balance responsible party are received during the matching process, their chronological processing is carried out in accordance with the order of receipt. It has to be noted that in the matching process starting after every turn of a quarter of an hour (xx.00, xx.15, xx.30, xx.45) the status of the nomination existing at the time of the quarter-hour turn is subject to matching all TSOs. Thus, the balance responsible party must ensure that identical schedule time series are available to both TSOs at the time of the quarter-hour turn at gate closure time, at the latest! Gate Closure Time The Gate Closure Time is the time of the quarter-hour turn at which a file with across-control-area modifications to schedules must be received by the TSOs concerned. It is obtained from the minimum lead time for the requested intra-day schedule modification amounting to 45 minutes (StromNZV, Arti-

8 cle 5, paragraph 2) or 15 minutes in the case of a schedule modification attributable to a power plant failure (StromNZV Article 5, paragraph 4) regarding the schedule nomination currently available to the TSO and accepted through an Acknowledgement Report (ACK). Schedule nominations implying across-control-area modifications which are received by the TSO after lapse of the Gate Closure Time, are rejected in the course of the formal inspection by means of an ACK. Examples: External schedule modification between two German control areas for the current day, first modification in the intra-day schedule nomination for the quarter-hour hrs.: Gate Closure Time = 13.15hrs. External schedule modification between two German control areas, schedule nomination due to power plant failure, first modification for the quarter-hour hrs.: Gate Closure Time =13.45hrs External schedule nominations with foreign control areas are subject to the more restrictive rules determined by the market rules on both sides of the borders in the countries concerned Admissible frequency of schedule nominations The admissible number/frequency of schedule modifications is not limited. It is only restricted by the versioning (ESS: max. Message/Time Series Version = 999 per day) Use of the Process Type element within an ESS Message In the German market system, there is currently no distinction made between the different process phases of a schedule day in the ESS process. During the introduction of the ESS process (Version 2.3) in 2004, a distinction according to process phases within an ESS message was deliberately foregone. For the concept described in this paper for automated handling of the intra-day process, such a distinction is not necessary either, as schedule files received can be clearly assigned to the respective process phases by the time of receipt and the day for which the schedule nomination is intended Matching Confirmation Report/Anomaly Report After every turn of a quarter of an hour and an additional stabilization time of about 1 minute, the TSOs matching process is started taking maximally 5 minutes: If at least one schedule modification has been received since the last matching process, the TSOs automatically exchange a file with cross-control-area schedules (CAS file). This file also contains the intended new schedule modifications (the most up-to-date schedule modification per balance responsible party at the quarter-hour turn). The result of the matching process is transmitted to the balance responsible parties concerned after finalization of the matching process in the form of complete CNF/ANO Reports. In the case of functioning inter-tso communication 1 and existing inconsistencies in schedule modifications, the following scenarios need to be distinguished: Gate Closure Time not yet reached: As part of the complete CNF-/ANO Report, the balance responsible party is notified in the ANO Report of identified inconsistencies. The balance responsible party has the possibility to send a correction of the modification to one or both TSOs. If the inconsistency was caused by the fact that the schedule change was only received in the following quarter-hour by one of the two TSOs, the balance responsible party needs not send a correction; successful matching is then undertaken during the following matching process after the end of the next quarter of an hour. 8 1 In the case of functioning communication, a comparative schedule sent by a CAS file from the partner TSO is available within the matching phase for all external schedule modifications of a balance responsible entity. Furthermore, all (registered) schedule modifications of a balance responsible party were sent to the partner TSOs by means of a CAS file and confirmed by the latter through a CAS-ACK.

9 Gate Closure Time exceeded: All values of the inconsistent (differing) schedule that were modified by the balance responsible party are overwritten (modified) by the previously valid values of the schedule version already received and confirmed before. The balance responsible party shall receive from the TSO a complete CNF/ANO Report. The modified schedule is part of the CNF Report; the modified values are specifically marked as such (see also specifications on the Modified und Imposed Time Series issue in Section 5.2). Where applicable, the ANO Report shows additional recognized inconsistencies which concern other schedules and can be corrected at a later time in accordance with the market rules. The current matching cycle is thus concluded for the balance responsible party concerned. If it wishes a change of schedule values modified to the previous values for which Gate Closure Time has not been reached yet, it must again announce this change to the two TSOs in a schedule nomination. If modified schedule values undershoot already the Gate Closure Time at the moment when the schedule nomination arrives at the TSO, the complete nomination is denied already in the result of the entry check. The balance responsible party is notified of that in the ACK Report. Where inter-tso communication is faulty, complete CNF-/ANO-Reports are sent to the balance responsible party after expiry of the 5-minute period on the basis of the matching status achieved so far. In this condition, matching will be continued by the TSO through manual operations, the result a- chieved being also made known to the balance responsible party by complete CNF/ANO Reports sent to it Requirements During the matching process, it has to be made sure for an intra-day modification request of a balance responsible party, in case there exist schedules to a partner control area going in opposite directions, that always both directions are coherently considered and verified. Otherwise, a situation may occur where the schedules in both directions are no longer netted. That means in particular: (1) If both directions are changed by the balance responsible party consistently with the rules and one of the two directions shows inconsistencies, the schedule modification to the other direction (showing no inconsistencies) cannot be confirmed either; (2) If one of the two modified time series going in opposite directions is still showing inconsistencies after the Gate Closure Time has been exceeded, always both opposite time series modified shall be modified to the version of these time series last confirmed. Example: A balance responsible party nominates intra-day schedules (C, D or E, F) at the responsible TSOs. The direction from TSO A >> TSO B (columns C and E) is correct in both nominations. At the time 8, there is an inconsistency in the direction from TSO B >> TSO A (columns D and F). If a control would now take place per direction only, the data for the direction from TSO A >> TSO B would be taken over as these data are correct. Concerning the direction from TSO B >> TSO A, the data of the version last matched (column B) would continue to be valid, as the two schedules in this direction show an inconsistency. The result would be a non-netted intra-day schedule (columns G and H) With a view to avoiding these inconsistencies, it is additionally verified whether both directions (TSO A >> TSO B, or TSO B >>TSO A) are correct. As a result, either the schedules in both directions can be adopted or, if there are any inconsistencies, both schedules are overwritten by the schedules already previously matched, which thus remain valid without any change.

10 10 Matched schedule Intra-day Intra-day Resultant version registration at registration at Intra-day TSO A TSO B registration (previous day) A B C D E F G H From control area TSO A TSO B TSO A TSO B TSO A TSO B TSO A TSO B To control area TSO B TSO A TSO B TSO A TSO B TSO A TSO B TSO A Version time Schedules in opposite directions would no longer be netted!

11 4. Examples of processing The processing diagrams only show the main data exchange. They do not enable any conclusion to be drawn about the transfer times of messages or processing times in the systems. 4.1 Faultless process flow A faultless process flow is shown in Figure A balance responsible party nominates its modifications at the TSOs concerned. At the end of the quarter-hour following the nomination, the TSOs will exchange CAS files. If matching could be successfully realized, the balance responsible party is correspondingly notified through a Confirmation Report. Trader TPS ACK TSO B CAS CNF TSO A 13:00 Time series matched Every 1/4h + 1 min data exchange between the TSOs Every 1/4h + 5 min matching of exchange programs 14:00 Change of schedule as from 2:00 p.m. Figure 1: Faultless process flow 4.2 Intra-day modification has not reached one of the parties addressed Figure 2 shows a faulty process flow. The balance responsible party s schedule nomination does not reach TSO B. At the end of the quarter-hour following the nomination, TSO A will send a CAS file to TSO B. The latter responds to the receipt of the CAS file by sending in addition to the ACK a CAS file with its data to TSO A. Trader TPS ACK TSO A CAS CNF ANO TSO B 13:00 Every 1/4h + 1 min data exchange between the TSOs Every 1/4h + 5 min matching of exchange programs Time series matched 14:00 Subsequent to the matching process, the two TSOs shall send an Anomaly Report to the balance responsible party. Change of schedule only possible from 2:15 p.m. Figure 2: The intra-day registration has not reached one of the parties addressed.

12 The balance responsible party answers with a new schedule nomination. It is left to the discretion of the balance responsible party whether it sends a new schedule nomination to both TSOs or only to the one that has not received the data before. At the end of the quarter-hour following the correction/re-nomination, the TSOs shall again exchange CAS files. If the matching process could be successfully implemented, the balance responsible party is notified of this result in the Confirmation Report. 4.3 Faulty intra-day modification is not corrected by the balance responsible party A faulty process sequence is shown in Figure The schedule nomination of the balance responsible party does not reach TSO C. At the end of the quarter-hour following the nomination, TSO B shall send a CAS file to TSO C. The TSO C responds to the receipt of this CAS file by sending in addition to the ACK a CAS file to TSO B. Following the matching process, both TSOs shall send a full Anomaly Report to the balance responsible party. In this case, however, the balance responsible party does not respond to the TSOs error messages. Trader TPS ACK TSO B CAS CNF ANO TSO C 13:00 Every 1/4h + 1 min data exchange between the TSOs Every 1/4h + 5 min matching of Exchange programs Trader may nominate until 45min before Renewed ANO Reiteration until deadline is undershot Matching not possible, resetting to last matched time series With the last confirmed time series (modified TS) With the last confirmed time series (matched former TS) Figure 3: Faulty registration long before deadline / not existent and not subsequently corrected by the balance responsible entity 14:00 Time series rejected, or modified to former TS Schedule change Gate Closure (45 min before) The transmission of the Anomaly Reports by the TSOs to the balance responsible party is continued as long as a cross-control-area error exists or the Gate Closure Time is reached for the modification in question. Reaching the Gate Closure Time for a time series, the latter is then reset (modified) to the time series last confirmed. This is communicated to the balance responsible party in a Confirmation Report.

13 13 5. Annex 5.1 Rules for the utilization of the Process Type element For the German market system, a solution was chosen according to which Intra-day modifications to schedules are not separately characterized. Every cross-control-area modification to a schedule which is communicated to a TSO after Gate Closure Time of the previous day is first regarded as an intra-day schedule modification. Whether the lead times applying to the process are observed is ascertained by means of the time of receipt of the schedule file and the schedule value that has been modified first. As the data base is the same for all processes, a characterization has to be given within the message so as to enable this message to be verified with regard to the correct lead time of 45 or 15 minutes, respectively. In the concept described in the present paper, the characterization of the message is realized through the message type within the ESS message. The reasons for this step are explained hereinafter. The ESS Implementation Guide in its version 2.3 [2] and the version 3.0 or 3.1 currently under discussion, apply different standards to the application of the Process Type element. The ESS Version 2.3 contains rules which can be interpreted to the effect that in the case of utilization of a different process type, a new message identification should be used at the same time even if the same data content is being used. (cf. ESS IG V2.3, Section Message Identification: description ) In the ESS Version 3.0 which has already been released, the introduction of the element domain and interlinking of Domain and Process Type require that a new Message Identification be applied if a different Process Type is utilized. (cf. ESS IG V 3.0). Furthermore, interlinking with the domain means that a message with a different process type can/must also have a different data content, e.g. only the data for the current intra-day modification. The German market system is designed in a way that the schedule file of a balance responsible party reflects the total trading activities of the latter. This principle is also determined in the German electricity network access regulation (StromNZV see [7]; Article 5; paragraph 1, last sentence) [ ] Schedules must be complete and permit a settled balance of the balancing group and thus of the control area concerned. Therefore, a transmission of extracts from the trading activity, which is possible but not mandatory according to the ESS 3.0, would be inconsistent with German market rules.

14 5.2 Utilization of Imposed and Modified Time Series in an ESS Confirmation Report In an ESS Confirmation Report, times series can be returned to a market participant as confirmed or imposed. In this respect, the following rules are determined for the German market system: Imposed Time Series An Imposed Time Series is a time series newly allocated by the TSO to the portfolio of a balance responsible party which has not been registered yet by the balance responsible party for this day. 1. The TS-ID is generated by the TSO as no time series with this constellation has been registered to that date by the balance responsible party. Hence, there is no TS-ID available which can be used by the TSO. Therefore, the TS-ID generated by the TSO and used for this time series is called Imposed TS-ID. 2. The Confirmed Message Version is used as version number of the Imposed Time Series. 3. In case the balance responsible party has not transferred any accepted schedule nomination to the TSO for the day in question, the version number 1 for the Imposed Time Series is returned. In this case, the elements Confirmed Message ID and Confirmed Message Version are not transmitted. 4. An imposed TS-ID allocated by the TSO may be overwritten once only by the balance responsible party with its own TS-ID in the case of a schedule re-nomination for the respective day. This TS-ID must then also be used for all subsequent updated schedule nominations Confirmed Time Series with the Modified status If values in a time series already registered are modified by the TSO, this time series is then a Confirmed Time Series with the status Modified. 1. The last Time Series Version accepted and transmitted by the balance responsible party is maintained as version number. 2. The modified schedule must be characterized in the Confirmation Report by a Reason Code at Time Series Level Status in a Confirmation Report 14 Schedule global position accepted Confirmed Time Series All time series mentioned in the balance responsible entity s portfolio were confirmed at the TSO by the market participants without any restriction Imposed Time Series Schedule global position partially accepted Confirmed Time Series specified time series: - has been confirmed to the TSO by the market participant without any restriction Reason Codes: A63 at TS-Level - modified by the TSO A43, A44 at IV-Level Imposed Time Series Can be issued only at the end of the respective deadlines. specified time series was newly put - into the portfolio by the TSO Reason Code: A30 at TS-Level Figure 4: Status in a Confirmation Report If a CNF Report was given the status A06 (Schedule global position accepted) that means that all schedules of the balance responsible party have been confirmed by the TSO without any change. However, if a CNF Report was given the status A07 (Schedule global position partially accepted), the

15 content of the CNF Report must be interpreted as a function of the question whether it is an Intermediate or a Final CNF: 15 Intermediate CNF Final CNF - The Report does not necessarily comprise the entire portfolio of the balance responsible party. Individual inconsistent schedules or schedules not transmitted by the counterpart, can be missing in the Intermediate CNF Report. They are transmitted, where necessary, to the balance responsible party in a separate ANO Report by specifying the concrete error. During the day-ahead phase, schedules received by one side only are neither transmitted in the CNF nor in the ANO Report to the balance responsible party. - The Intermediate CNF Report may include modified or imposed time series. - The Report comprises the entire portfolio of the balance responsible party. The time series transferred are binding and are used for the balancing group s accounting. The status A07 of a Final CNF Report points out that at least one of the time series included was modified or imposed by the TSO. 5.3 Glossary of terms Confirmed time series: A balance responsible party considers a time series to be confirmed (= relevant to billing) if this time series has been transmitted to it by a TSO in a Confirmation Report. Within the Confirmation Report, this time series can be transmitted as Confirmed TS in an unchanged or in a modified form or as Imposed TS. Confirmed time series (schedules) are also relevant to the TSO in terms of billing, and additionally in terms of control where confirmed schedules across-control areas are concerned. The latter are automatically or manually confirmed in the result of a CAS check. Accepted time series: A time series is given the status accepted if it was contained in an ESS message that was confirmed in an ACK with the Reason Code A01 (Message fully accepted). It is used by the TSO for the further matching process.

16 5.4 References [1] EIC; The ETSO Identification Coding Scheme, A common Identification System for the electricity Industry, Version 2 Release 1; 10/11/2002, [2] ESS; ETSO Scheduling System; Implementation Guide, Version 2 Release 3, dated 29/04/2003, [3] ESS; ETSO Scheduling and Settlement System; Code List, Version 2 Release 0; dated 29/04/ [4] Transmission Code 2003; Network and System Rules of the German Transmission System Operators; August 2003; Verband der Netzbetreiber e.v. beim VDEW; Berlin; [5] Transmission Code 2003; Network and System Rules of the German Transmission System Operators Appendices -; August 2003; Verband der Netzbetreiber e.v. beim VDEW, Berlin; [6] Schedule nomination in Germany by means of ESS; Version 1 Release 0; dated 06/08/2003; Verband der Netzbetreiber e.v. beim VDEW, Berlin; [7] (Electricity network access regulation) - StromNZV; Verordnung über den Zugang zu Elektrizitätsversorgungsnetzen; (Stromnetzzugangsverordnung StromNZV); of 29/07/2005; 16