INDEPENDENT POWER TRANSMISSION
OPERATOR S.A
Operation & Control Department
Power Control Branch
22, Asklipiou St. – GR 145 68 KRIONERI
Justification of the Day-Ahead Scheduling and Actual Operation deviations for
22.11.2013
The Independent Power Transmission Operator (IPTO) publishes a general valuation of the Actual
System Operation (ASO) in comparison to the corresponding clearing results of the Day-Ahead
Scheduling (DAS).
According to the ASO data and the corresponding DAS clearing, the energy demand of the Load of
133618[MWh] (including 131306[MWh] of supplier’s Load Declarations and 2312[MWh] of
calculated system losses), was more than the ASO total load demand of 132347[MWh] by
1271[MWh]. This difference was due to the deviations between Load Declarations and Actual
load.
The comparison of percentage energy production (Thermal, gas, hydro etc) on the base of the
total load, between DAS and ASO, is analyzed as follows:
APPLICATION
PERCENTAGE SUPPLY OF DEMAND
THERMAL
RENEWABLE
HYDRO
INTERCONNECTION
TOTAL DEMAND
DAS
74,50%
14,94%
3,90%
7,27%
100%
ASO
76,65%
10,84%
4,76%
8,54%
100%

The ASO total energy production by Renewable Energy Sources (RES) of 14341 [MWh],
(10,84%) was 5616 [MWh] less than the total forecasted RES energy injection of DAS
19957[MWh], (14,94%). This difference was due to forecast error.

The ASO total energy production of thermal units of 101448 [MWh], (76,65%) was
1901[MWh] more than the total scheduled thermal production of DAS 99547[MWh],
(74,50%). This increase of production by thermal units was due to the decrease of RES
energy injection.

The ASO total energy production of hydro units of 6301[MWh], (4,76%) was 1091[MWh]
more than the total scheduled hydro production of DAS 5210[MWh], (3,90%) including
4589[MWh] of mandatory hydro energy injection. This difference was due to the ASO
requirements of secondary regulation and the deficit of production by Renewable Energy
Sources (RES).

The ASO total pumping energy of 1047[MWh], was 232[MWh] more to the total scheduled
pumping (Priced Loads) of DAS 815[MWh] due to lack of secondary reserve down.

The ASO net interconnections energy exchange (imports) of 11304[MWh], (8,54%) was
1585[MWh] more than the total net scheduled exchanges of DAS (imports) 9719[MWh],
(7,27%). This difference was due to the deviations between DAS and ASO related to the
exchange programs via the HVDC Link. The DAS solution made with the long term yearly
exchange programs and the DS / ASO solution made with zero program (The HVDC Link
remain out of order). Some additional reasons for the deviation was the interconnected system
regulation requirements and the deviations of the actual thermal units’ capacity.

The HVDC Link ARACHTHOS (GREECE) – GALATINA (ITALY) out of order from 00:00 till 24:00
CET due to fault occurred to the converter smoothing coil in Galatina.