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4.3 BAL.3 INDICATOR: NET TSO BALANCING VOLUME AS % OF
MARKET VOLUME VS. BAL.4 INDICATOR: NET SHIPPER
IMBALANCE VOLUME AS % OF MARKET VOLUME
The establishment of a residual balancing role
for the TSO while leaving the primary balancing
responsibility to the network users is one of the
key principles of the NC BAL.
A second indicator (BAL.3) related to the resid-
ual balancing role for the TSO is proposed taking
into account the net TSO balancing volume at
the end of the gas day. Only those gas days are
taken into account when TSO balancing actions
occurred. BAL.3 gives an indication if relatively
more gas is sold by the TSO to the market or
bought by the TSO from the market due to bal-
ancing purposes relatively to the market (entry)
volume at the end of the gas day.
In this chapter the daily BAL.3 indicator is com-
pared to the daily BAL.4 indicator which aims at
assessing whether the overall system is in bal-
ance on a day-on-day principle and whether the
network users contribute sufficiently to keeping
the overall system in balance. As shippers are
allowed to balance their portfolios on a daily ba-
sis, aggregated shipper portfolio data is used for
BAL.4 to assess whether network users contrib-
ute sufficiently to keeping the overall system in
balance.
The assumption is that the TSO is balancing the
system by the end of the gas day taking the net
shipper imbalances at the end of the gas day
into account. Both indicators should be mini-
mised and should have a limited range. Where
differences of the two indicators per balancing
zone/country occur, further explanation might
be needed to understand better how the system
is overall balanced by the TSO on a daily basis.
An example of BAL.3 in a balancing zone with
general explanations related to the graph can be
found in Map 5 below.
It shows the range and the fluctuation of the net
TSO balancing volumes conducted by the TSO
at the end of the day relatively to the daily market
volume in a balancing zone or a trading region
(e. g. TRS). The maximum range of the relative
net TSO balancing volumes is limited with the
minimum and maximum of the performed TSO
volume at the end of the day. The blue box
indicates the range in which the TSO is perform-
ing 80% of its balancing volumes relatively to
the market (entry) volumes of a balancing zone.
An example of the indicator BAL.4 in a balanc-
ing zone with general explanations related to the
graph can be found in Map 6 on page 107.
It shows the range and the fluctuation of the net
shipper imbalance volumes on a daily basis
taken into account those days when shipper
imbalances occur during GY 2015/2016. The
maximum range of the relative net shipper
imbalance volumes is limited with its minimum
and maximum volumes during the afore
mentioned period. The orange box indicates the
range of the net volume of shipper imbalances
relative to the market (entry) volume of a balanc-
ing zone (BAL.4) on 80% of the days when any
shipper imbalances occur.
– 5%
– 10%
– 15%
– 20%
25%
20%
10%
15%
5%
0%
Balancing zone
(no. of days with TSO bal.action)
Min
Max
On the remaining 10% of the days when TSO is performing balancing actions, the
net TSO balancing volumes relative to the market entry volume of a balancing
zone (BAL.3) have a range between +5% and max. +15%. This means on 10%
of the days when the TSO is performing balancing actions, he is selling (more)
gas to the market at the end of the day in a range of 10%.
On the remaining 10% of the days when TSO is performing balancing actions,
the net TSO balancing volumes relative to the market entry volume of a balanc-
ing zone (BAL.3) have a range between min. −15% and −5%. This means on
10% of the days when the TSO is performing balancing actions, he is buying
(more) gas from the market at the end of the day in range of 5%.
On 80% of the days when TSO is performing
balancing actions, the net TSO balancing
volumes relative to the market entry volume of
a balancing zone (BAL.3) have a range between
−5% and +5%. This means that the TSO is
sometimes selling more gas (+) to the market
as well as sometimes buying gas (−) more from
the market at the end of the day in a range
of 10%.
Map 5:
Example with explanation of the daily BAL.3 indicator in % on days with TSO balancing actions in GY 2015/2016
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