Before the
MAHARASHTRA ELECTRICITY
REGULATORY COMMISSION
13th
floor, Centre No.1, World Trade Centre, Cuffe Parade, Mumbai 400 005.
Tel. 22163964
/ 22163965, Fax No. 22163976
E-mail mercindia@mercindia.com
Website: www.mercindia.com
CASE NO. 20 & 21 of 2003
In the matter of
Access by REL to
intervening transmission facilities of TPC and MSEB
Dr Pramod Deo, Member
ORDER
Dated: 4th
February, 2005
In
its Order dated 29th January, 2004 on earlier Applications by BSES
Ltd. (now Reliance Energy Ltd. (REL)) seeking access to intervening
transmission facilities of Tata Power Co Ltd. (TPC) (Case No. 20 of 2003) and
Maharashtra State Electricity Board (MSEB) (Case No. 21 of 2003), the
Commission has stated, inter alia that:
"By this Order, therefore, the
Commission requires MSEB and TPC, under Section 35 of the EA, 2003, to provide
the use of their intervening transmission facilities to BSES to the extent of
surplus capacity available with them.
However, such use shall be limited to the sourcing of power by BSES from
any bulk licensee or their own generating stations within or outside the
State. The parties concerned would be
free to approach the Commission in case of any genuine dispute regarding the
extent of surplus capacity available, as provided for in Section 35. In case no such dispute is raised, the
parties should mutually decide the rates, charges and terms and conditions for
the provision and use of the intervening transmission facilities as envisaged
in Section 36. Mutual agreement on
these matters would be in the best interest of the parties. In case, such agreement cannot be reached
within a reasonable period of time, either party is entitled to approach the
Commission for determination under the proviso to Section 36(1). In that event, however, the Commission would
expect evidence that negotiations have been held in good faith and all
reasonable efforts have been made to arrive at mutual agreement.
Citing
the Order, REL have again approached the Commission on 12th April,
2004 in separate Applications seeking that the Commission
(a)
Adjudicate
the extent of surplus capacity available with MSEB for use of intervening
transmission facilities by REL to the extent of 800 MW (Padge to Boisar, Padge
to Borivli, Padge to Trombay), and the surplus capacity available with TPC
considering REL’s requirement of 730 MW at nine of the existing interconnection
points;
(b)
Specify
the rates, charges and terms and conditions for REL's use of such intervening
transmission facilities.
2. In
respect of TPC, REL have stated that, as allowed by the Commission and as
provided under the proviso to Section 35 of the Electricity Act (EA), 2003,
they are approaching the Commission again since there is a dispute regarding
the availability of surplus capacity inspite of REL’s efforts, and TPC have
also raised various issues regarding the need for a State Grid Code, etc., to
determine spare capacity, and sought to link many other points with the
matter. TPC had also not indicated the
rates, charges, and terms and conditions to be negotiated inspite of
repeated requests by REL, as
envisaged under Section 36.
3. With regard to MSEB, REL have stated in
their Application that, following the Commission’s last Order, they had
approached MSEB, who had asked for various clarifications. These had been given, and REL had also
suggested a meeting. However, there was
no response from MSEB. MSEB had, in
their letter seeking clarifications dated 10.3.2004, indicated that the
transmission network around Padge is already loaded to capacity. MSEB have also not responded to REL’s plea
to indicate rates and terms and conditions to be negotiated.
4. In
their Reply dated 5th May, 2004 TPC have denied not responding
positively to REL. However, they found
it difficult to accede REL’s request in the absence of clarifications regarding
the need for a State Grid Code for determining the spare capacity, and the
basis for deciding the wheeling and transmission charges in the absence of any
guidelines from the Commission. TPC have pointed out that the Commission has
initiated a process for intra-state ABT to lay down the guiding principles for
allowing open access. TPC have also
drawn attention to the Commission’s reference in its Order that REL should show
that new power purchase agreements will not affect REL's quality of service to
their consumers. TPC have submitted
that, being an interconnected system, TPC need also to satisfy themselves that
providing such open access would not jeopardize TPC’s own consumers. TPC also required certain further
details with reference to the points
listed in the CERC Order dated 30th January, 2004. TPC have argued further that REL have asked
for open access including 22 / 33 KV busbar which is used by TPC for
distribution. However, while open
access has been allowed by the Act on the transmission network, it has not yet
been granted on distribution. Further,
the individual sub-stations indicated by REL are TPC’s distribution
sub-stations, the capacity of which is limited to the capacity of installed
distribution transformers. As such,
giving open access to them would correspondingly reduce TPC’s ability to meet
the load of their own consumers. As far
as the 220 KV Borivli point is concerned, it is only for standby and not for
normal supply. TPC have also raised
various issues regarding the implications of power supply in Mumbai if an
outside source of uncertain power is relied upon. Moreover, the transmission capacity constraint is evident from
the fact that, when both units tripped on 13th April, 2004, REL were
not in a position to meet their full requirement from the existing transmission
network and had to resort to load shedding.
Other issues with regard to commitment of payment of standby charges,
need for a PPA, two part tariff, etc., have also been mentioned in TPC’s
Reply. Summarizing the distinction
between transmission and distribution, TPC have finally stated that, out of
REL's request for 730 MW, only 145 MW pertains to transmission open access, the
balance being 22/33 KV which is a distribution level voltage. Even this quantum has been asked for at
Borivli, which is to be used only for standby and not for regular supply.
5. In
their Reply dated 5th May, 2004, MSEB have submitted that they had
conducted load flow studies on the circuits proposed by REL for evacuation of
power from Padge for a typical system loading and based on CEA guidelines for
line loading. On that basis, MSEB had
concluded that, considering other circumstances cited, the 400 KV Padge-Kalwa
section would be loaded to capacity to meet MSEB’s internal requirements. Therefore, injecting additional 350 MW power
on the Kalwa-Borivli line would cause overloading of the underlying 220 KV
network leading to system instability.
In case of outage at Tarapur,
the situation on the 220 KV Kalwa-Mulund-Borivli and 220 KV Kalwa-Borivli lines
would be further aggravated. With
regard to Padge-Trombay, the two relevant circuits are also loaded to the capacity. As far as Padge-Borivli is concerned,
considering the possibility of Tarapur being under outage, injecting additional
100 MW would critically overload both the MSEB and the REL networks. MSEB had
communicated the load flow study findings to REL. MSEB are also conducting further load-flow studies under various
contingencies and scenarios to determine the extent to which capacity is available for providing open access, the
results of which would be submitted in due course. MSEB have urged that guidelines be given for ensuring system
stability in the absence of balancing markets or an intra-State ABT.
6. At
the hearing held on 10th May, 2004, Shri J. J. Bhatt, Counsel for
REL, referred to para 23 of the Commission's Order, and submitted that mutual
agreement could not be arrived at. He further submitted that MSEB in their
Reply dated 5th May 2004 had submitted, in substance, that they do
not have surplus capacity, and drew attention to the following paras of the
Reply :
"2. Subsequent to the Order, REL, vide its
letter dated February 10, 2004 requested MSEB to provide open access on its
transmission system and the use of intervening facilities up to 800 MW at:
a.
Padghe to Boisar (100 MW)
b.
Padghe to Borivali (350 MW)
c.
Padghe to Trombay (350 MW)
REL also requested MSEB to
indicate reasonable rates, charges and terms and conditions for the same.
3. In its reply dated March 10, 2003
MSEB requested REL to provide further information.
4. In its letter dated March 12, 2004 REL provided details
of the voltage level at which the power was to be injected into the system and
the evacuation plans from Padghe. REL
plans to evacuate power from Padghe as follows:
a.
100 MW on the two 220 KV circuits going from Padghe to Boisar. One
circuit goes directly to Boisar while the other circuit goes to Boisar via
Nalasopara.
b.
350 MW from Padghe to Borivali via the Padghe – Kalwa – Mulund -
Borivali circuit and the Padghe – Kalwa - Borivali circuit.
c.
350 MW from Padghe to Trombay via the Padghe - Kalwa - Mulund- Trombay
circuit and the Padghe – Kalwa – Trombay circuit.
5. MSEB conducted load flow studies on the circuits proposed
by REL for evacuation of power from Padghe. The load flow studies were
conducted for a typical system loading. The findings of the load flow studies,
based on the CEA guidelines for line loading, are as follows:
a.
Transmission of 350 MW power from Padghe to Borivali. Presently 500 KV
HVDC Chandrapur – Padghe bipole line is being operated as monopole due to
technical constraints. It is expected that by 2nd week of May 2004,
the bipole operation will commence. Post commencement of the HVDC bipole
operation, 1500 MW power will be transmitted at 400 KV Padghe bus over HVDC
line. Under such circumstances, 400 KV Padghe – Kalwa section will be loaded to
its capacity to meet the internal requirement of MSEB. Therefore, injection of
additional 350 MW power, as stated by REL, would cause the overloading of the
underlying 220 KV network.”
7. Counsel for REL quoted further from
MSEB’s Reply as follows:
“Post commencement of the HVDC bipole operation,
1500 MW power will be transmitted at 400 KV Padghe bus over HVDC line. Under
such circumstances, 400 KV Padghe – Kalwa section will be loaded to its
capacity to meet the internal requirement of MSEB. Therefore, injection of
additional 350 MW power, as stated by REL, would cause the overloading of the
underlying 220 KV network i.e. 220 Kalwa – Mulund – Borivali and 220 KV Kalwa –
Borivali lines, leading to system instability.”
MSEB have also stated that:
"Padghe – Kalwa section
is already loaded to its capacity 220 KV Kalwa is further connected to Trombay
via 220 KV Mulund sub-station. REL has proposed to tap these two circuits at
their Chembur sub-station so as to transmit 350 MW into their network. As these
two circuits i.e. 220 KV Kalwa – Trombay and Kalwa – Mulund - Trombay are
loaded to their capacity, injecting additional 350 MW power will make the
circuits overloaded”.
“There are two 220 KV circuits from Padghe to Boisar. One of which is
directly connected to Boisar and the other is connected to Boisar via
Nalasopara. REL’s 220 KV Dahanu – Varsova s/c line is tapped at 220 KV Boisar
presently kept open. When TAPS units are under outage requirement of MSEB
Boisar sub-station is met through 220 KV Padghe – Boisar and 220 KV Padghe –
Nalasopara – Boisar line. Under these circumstances injecting …..”.
8. Shri Gaurav Joshi, MSEB Counsel
circulated a schematic diagram of the circuit to illustrate the position. He submitted that MSEB would require some
time to conduct the further load flow studies.
Referring to the diagram, he submitted that it was impossible to meet
REL’s requirement of 350 MW on a line which was not capable of carrying that
load. MSEB Counsel pointed out that
REL and MSEB had different distribution areas and, by providing the facility,
MSEB would earn something, but they just did not have the capacity. This had been explained to REL through
correspondence. MSEB had said that the
issue could be discussed at a meeting, and referred to the letter annexed to
MSEB's Reply.
9. Counsel for MSEB referred to the
Annexures to their Reply to indicate that the MSEB line was overloaded and did
not have any surplus capacity. He further submitted that circuits from Padghe
to Boisar via Nalasopara or directly were already loaded up to 60-80% of their
normal capacity when there is no outage or breakdown. To a query from the Commission,
he stated that these were 2 independent single circuits, one from Padghe
– Nalasopara – Boisar and the other from Padghe to Boisar. MSEB’s average use per circuit was 70 – 80
MW, and on an average the maximum load went up to 100 MW. The Commission enquired from MSEB as to the
base load and peak load of the circuits and observed that, as MSEB had
conducted load flow studies, they should have come with all the details. The
representative of MSEB submitted that the line loading data is available for
REL to see. The Boisar sub-station was
for evacuation of Tarapur. If Tarapur was not available, MSEB would not be in a
position to supply power. He explained that all the networks were from Padghe
(eastern side) and Kalwa (western side) and all these networks are to meet
contingencies. Counsel for MSEB
submitted that even if both the circuits were put together, the capacity would
still be 260 MW and REL wanted to evacuate 350 MW.
10. The representative of MSEB submitted
that, if necessary, a Committee headed by MSEB with representation from both
TPC and REL could examine the position. Counsel for REL suggested the formation
of a Committee headed by an independent person, and that WRLDC could be
involved. All three parties agreed to
participate in the Committee. Dr. Ashok
Pendse of Mumbai Grahak Panchayat also agreed with the approach, and suggested
Prof. Khaparde of IIT, Powai as a Member of the Committee since he had
expertise in the technical matters involved. The Commission observed that the
Chairman of the Committee could be from the Western Region Electricity Board
(WREB).
11. The representative of TPC submitted that
the Order dated 29th January, 2004 stated that REL could obtain power from
their own generation elsewhere or from a bulk licensee. However, REL had not yet disclosed the
generating station or the bulk licensee from whom they wanted to bring
power. The Order also states that such
new purchase arrangements should not affect the quality, continuity and the
reliability of REL's services to consumers in their licensed area, and asked whether REL had satisfied these
conditions. Instead, REL had floated
public enquiries for different quantum of power at different times. With this method of power coming through the
MSEB network, he submitted that the islanding system would collapse. The Commission observed that the matter was
a technical one and the relevant points could be raised in the Committee.
12.
Regarding the Boisar and
Tarapur expansion 3 and 4, the representative of MSEB submitted that the Power
Grid Corporation was going to establish a 400 KV sub-station at Boisar and had
requested MSEB to provide two lines at Padghe. Thus, there is a lot of network coming up, not restricted to
MSEB. Perhaps in a year's time, there
would be greater possibilities.
13.
The representative of TPC submitted
that the issue of what is transmission and the point at which distribution
starts also needed to be considered. He
further submitted that REL were asking for power from TPC at 22KV. He queried as to whether REL were entitled
to evacuate power from 22KV, or whether REL could set up own transformers and
then step down. He further submitted that REL wanted to take advantage of the
system which TPC had created. There
were many conflicting provisions on the subject of what is transmission and
what is distribution.
14.
Counsel for REL referred to paras
6, 7 and 9 of TPC's affidavit dated 5th May 2004 as under:
Para 6:
“The Hon’ble Commission in
the process of defining the network elements, included in transmission network
of TPC and MSEB over which open access can be granted. BSES has asked for open
access on TPC’s network including 22/33 KV bus bars. This network is being used
by TPC for distributing power in its licensed area to its own consumers
including distribution licensees. While open access has been allowed by the Act
on transmission network it has not been granted yet on distribution network of
a licensee.”
Para 7:
“22 and 33 KV is a
distribution voltage level all over the world and individual sub-stations
indicated by REL are TPC’s distribution substations. The capacity at these
substations is limited to the capacity of installed distribution transformers.
If REL is given open access on these distribution transformers the TPC’s
ability to meet load of its own consumers and other licensees gets restricted
by equivalent margin.
Para 9:
“TPC needed to know
details of REL’s proposal to bring in power from outside, both in terms of
quantity and duration, active and reactive load flow at each point of injection
and delivery so that the impact on TPC has enquired about this in its letter
dated 27th February 2004. The surplus capacity, if any, on TPC’s
network was to be ascertained only after these queries were answered by REL.
Since, REL indicated distribution points for open access TPC could not indicate
any surplus capacity available on transmission network. Regarding 220 KV
Borivali point, TPC has already stated that it is only for standby type of
service and not for normal supply.”
In this context, Counsel submitted that REL wanted
open access up to the various outlet points of 22/33 KV, and not from the
outlet points. The desirability, which
was related to capability, was for the Commission to determine and the
Committee to address.
15.
As far as the legal aspect is
concerned, Counsel for REL referred to the definition of distribution system
under Sec. 2(19) of the Electricity Act, 2003:
“Distribution system means a system of wires and
associated facilities between the delivery points on the transmission lines or
the generating station connection and the point of connection to the
installation of the consumers.”
Counsel for REL submitted that if 22/33 KV was
treated as the delivery point, then up to 22/33 KV in law would be
transmission. He referred to the
definition of transmission lines under Sec. 2(72) of the Electricity Act, 2003:
“Transmission line means all high-pressure cables
and overhead lines (not being an essential part of the distribution system of a
licensee) transmitting electricity from a generating station to another
generating station or a sub-station, together with any step up and step down
transformers, switchgear and other works necessary to and use for control of
such cables or overhead lines and such buildings or part thereof as may be
required to accommodate such transformers, switch-gears and other works.”
He further submitted that, reading these two
definitions together, the transmission lines ended at the 22/33 KV outlet point
and thereafter REL were entitled in law to access up to the outlet of 22/33 KV,
which could be denied by the Commission by giving reasons after considering the
findings of the Committee.
16.
The Commission observed that only
high voltage line was defined, whereas high pressure cables were not. Counsel for REL referred to the definition
of high voltage line under Sec 2(35) of the Electricity Act, 2003:
“High Voltage line means an electrical line or cable
of a nominal voltage as may be specified by the Authority from time to time.”
Dr.
Pendse of MGP opined that up to 66KV network was transmission network and below
66KV was distribution network. The Commission observed that, as per the
definition cited by REL Counsel, it seemed that up to 33/22 KV was also a part
of the transmission network and 33 KV was the delivery point.
17.
The Commission queried as to
whether the step down transformers were also part of the transmission
network. Counsel for REL submitted that
they were not a part of the transmission system if step down transformers were
an essential part of the distribution system. He further submitted that REL
were a distribution licensee and that they bought power from TPC as a bulk
licensee. He further submitted that all assets of TPC which provided power to
REL at different points constituted the transmission facility. To a query from the Commission, Counsel for REL submitted that they were
seeking to bring in power from other sources that would replace the power REL
purchased from TPC, i.e. it is only a replacement. He submitted that he was essentially on the legal aspect. There might be commercial considerations
involved, and they could also be gone into by the Committee. The Commission observed that the definition
of distribution system extended to the connection right up to the generator,
and that the generator could be connected even with 400 KV. Thus the distinction between transmission
and distribution depended on the specific circumstances of each case. Counsel for REL agreed that both the
definitions overlapped in this sense.
The representative of MSEB submitted that the Committee would not be in
a position to go below 33 KV as far as MSEB are concerned. Counsel for MSEB submitted that MSEB also
needed clarifications as to where REL were intending to get the power up to
Padghe, and whose transmission facility REL were intending to use to bring
power uptil there.
18.
The representative of TPC submitted
that the various stations from where REL had asked for open access were all
essential parts of the distribution system. He also drew attention to para 13
of TPC’s comments dated 5th May 2004 as under:
“None of the issues raised
by TPC can be termed unconnected issues.
TPC has always shown its willingness to provide open access but on its
transmission network. The issues termed
as unconnected are given below:
i. In the open access regime, the present
standby arrangement would also undergo a change. If the present standby
arrangement were to continue, REL would need to commit payment of standby
charges as indicated in TPC APR for 04-05 if approved by the Commission.
ii. If TPC were to meet the said standard
requirement, then it needs to keep one of its units online for all time to
come. Who would absorb and pay for such technically minimum generation as would
be necessary for keeping this unit online.
Also REL would be required to pay as per two-part tariff for such
standby power - the capacity charge and energy charge, the latter being on the
maximum incremental cost of the marginal generation.
iii. If TPC were not obliged to meet the
standby requirement of REL, then treatment of TPC’s generating capacity
rendered surplus by REL sourcing power from outside needs to be decided.
iv. If TPC does not provide standby power, it
is necessary to know the source of standby power for REL in case of failure of
such outside supply.
v. Finalisation of standard quantum and the rate to be paid by REL
to MSEB/TPC providing standby for power procured from third parties is an
issue. TPC share of standby quantum and
the amount should be reduced consequent to reduction in the TPC load.”
“If REL proposes sourcing
its requirement from third parties.
vi. PPA between TPC and REL needs to be finalized and
approved by MERC.
vii. REL may have to enter into a two-part tariff with TPC since it
would tie up TPC capacity, which may not be commensurate with energy off take.”
He submitted that all these key points had
commercial implications. He further submitted four important issues on which a
comprehensive view had to be taken:
(1) The stranded cost of TPC if REL purchased power
from another supplier;
(2)
The
quality, continuity and reliability, which the Commission had insisted upon in
its Order dated 29th January 2004;
(3)
The
power procurement process, which would require to be approved by the
Commission, and the use to which the power is put;
(4)
If
the whole open access was given in the future, then what would be the impact on
the tariff being decided by the Commission for REL.
19.
Counsel for MSEB submitted that
only the limited issues directly involved in the present cases should be
referred to the Committee or else no report would be forthcoming. The
Commission directed the parties to file affidavits with suggested terms of
reference and other details within two weeks.
The Commission also directed MSEB to make available the past data of
transmission capacity on their website or if, they did not have past data, then
the data from 1st April 2004 onwards.
20. Subsequent
to the hearing, REL, TPC and MSEB submitted their suggestions with regard to
the terms of reference of the Committee proposed to be set up. After considering these suggestions, the
Commission sought the findings and advice of a Committee chaired by the
Member-Secretary, Western Region Electricity Board with representatives of the
Western Regional Load Despatch Centre, the three Parties, and Prof. S.A.
Khaparde, Department of Electrical Engineering, IIT, Mumbai with the following
terms of reference :
(a)
Capacity
availability on corridors on which REL plans to bring power
(b)
Capacity
on the relevant transmission systems of MSEB and TPC
(c)
Pricing
of reactive power
(d)
Balancing
mechanism required to be established
(e)
Equipments
required to measure and report energy flow
21. The
Committee submitted its Report vide letter dated 13th August, 2004,
signed by all the Parties / Members. It
is worthwhile reproducing the following conclusions contained in Chapter 3 of
the Report, which are as follows :
"3.1 Capacity
available on the corridor on which REL plans to bring power:
REL have indicated that the
injection is at 220 kV Padghe. The
corridors from where the power is coming to Padghe was from sources outside STU
network the details of which was not mentioned by REL and cannot be commented
upon by the Committee, as it is beyond the STU network.
3.2 Capacity
on the relevant transmission systems of MSEB and TPC:
Two sets of simulation were
carried out, one by MSEB and other by WREB.
MSEB had simulated Base Case with peak and off peak load condition and
case with injection of 800 MW at Padghe (Annex. 2). WREB simulated Base Case with peak condition and case with
injection of 800 MW injection at Padghe and also the effect single line
contingency. Also the new case of 300
MW injection at Padge and load of 145 MW at Boisar was simulated by WREB
(Annex. 3). From the MSEB simulation it
is seen that as the 800 MW power is injected at 220 kV Padghe the following
lines are over loaded (above SIL of 132 MW).
220 kV Kalwa-Salsette D/C flow was 257 MW per circuit, 220 kV
Padgha-Colorchem s/s flow was 229 MW, flow on 220 kV Kalwa-Colorchem s/s was
158 MW which is beyond the SIL capacity.
Further in the base case, without any injection, the flow on 220 kV Kalwa-Salsette D/c is 175
MW each for the case considered. Thus
as the injection at Padhe is increased the above lines are getting over loaded. From the results of WREB simulation the
flow for 220 kV Kalwa-Salsette was 150 MW each in the base case without
injection of power at Padghe and increases to 265 MW each with 800 MW injection
at Padghe. Also the total flow from
Padghe to Kalwa in WREB case with injection considered, is 560 MW whereas in
MSEB case it is 559 MW. However WREB
simulation does not include the LILO at Colorchem, being a regional
simulation. Thus the results after
injection are similar for both these independent studies. Further with the contingency of one 220 kV
Kalwa-Salsette line being out, the flow on the other circuit increases to 444
MW which indicates tripping of the other circuit also. MSEB representatives observed that 220 kV
Kalwa-Salsett D/c lines are generally loaded in the range of 200 to 400 MW
(total) for most of the time. Hence
these lines do not appear to have surplus capacity presently. As the power flow on the gateway to TPC system is itself beyond the capacity,
the question of evaluating transmission capacity in TPC was not done. The SIL loading was taken as 132 MW as per
CEA guidelines. REL representative
stated that line loading as a function of length, as per CEA guidelines should
be considered. However, the rest of the
Committee members stated that contingencies should also be considered as per
CEA guidelines. In the present case the
contingency of one of the 220 kV Kalwa-Salsette D/c line being out was
considered which resulted in overloading beyond capacity. Hence other contingencies like tripping of
one 500 MW unit etc. were not considered as they are more severe than the line
contingency.
3.3 The case referred by REL representative
with 145 MW at Boisar radialy at 220 kV is slightly different. Boisar is an existing MSEB station connected
to 220 kV Padghe and 220 kV Tarapur Atomic Power Station (TAPS) which in turn
is connected to "South Gujarat system with a number of Central and State
generation. This new case was simulated
in WREB. When 330 MW is injected at
Padghe, out of the 145 MW only about 88 MW is fed from Padghe side and the rest
of the load is fed by an increase in the 220 kV Tarapur-Boisar line with the
flow touching about 210 MW or so.
Already this line is loaded to 189 MW in the base case and in real time
also to control the loading of the same sometimes one 220 kV Padghe-Boisar ckt
needs to be kept out. It is an old line
and any tripping of the same could affect the evacuation of TPAS power and may
endanger the security of a nuclear
power station. Hence any possibility of
bringing power on this corridor as well as through the other corridor mentioned
in 3.1 is also ruled out.
3.4 Pricing of Reactive power : Till such
time MERC fixes the price of reactive power, the Committee felt that existing
penal rate for reactive power adopted by CERC may be followed.
3.5 Balancing mechanism required to be
established : Intra-State ABT may meet the requirement of balancing
mechanism. This will be as per the
guideline issued by MERC.
3.6 Equipments required to measure and
report energy flow : Real time data at SLDC Kalwa along with Availability Based
Tariff complaint Special Energy Meters (SEMs), would be required at the point
of injection and delivery."
22. The
matter was further heard on 26th October, 2004 by a single Member
Bench consisting of Dr. Pramod Deo, Shri Velayutham having recused himself
inasmuch as he had been the Chairman of the Committee which submitted the
Report, in his earlier capacity as Member-Secretary, WREB.
23. At the hearing on 26th October,
2004 Shri. Cooper, Counsel for REL, submitted that according to the Committee's
report there exists no surplus capacity for making available the open access
sought to TPC and MSEB's intervening transmission facilities. However, the entire report proceeds on the
basis of adoption of Surge Impedence Loading (SIL) criteria. It ignores
certain other basic criteria, which
ought to have been taken into consideration in determining whether or not
surplus transmission capacity is available for REL. Shri. Cooper quoted para
4.1 of the CEA Manual on Transmission Planning Criteria, which reads as
follows:
"4.1 Permissible line loading limit
depend on many factors such as voltage regulation, stability and current
carrying capacity (thermal capacity) etc. While Surge Impedence Loading (SIL)
gives a general idea of the load capability of the line, it is usual to load
the short lines appreciably above SIL and because of the stability limitations,
to load long lines lower than SIL."
Thus, Shri. Cooper
submitted that SIL could, according to the CEA, be only one of the guiding
factors, and other criteria also required to be looked at, viz. thermal
capacity, voltage regulation, etc.
Moreover, assuming SIL is to be the criteria, one must look at the line
length. If the line length is longer, then a discounting factor has to be applied
and a lesser availability can be concluded.
24. Shri. Cooper further submitted that
according to the CEA guidelines, the maximum loading of the 220 KV is 132 MW
for line length of 500 KM’s. If this is to be the criteria and if the SIL is
132 MWs, obviously 2.5 times could work out to about 330 MWs. REL want to use
the Kalwa Salsette Double Circuit (D/c) line, which extends for a distance of
approximately 10 KM’s. It could, therefore, take a load of 660 MWs if we take
into account the line length, which is what the CEA has said. Similarly as far
as the Tarapur-Boisar line is concerned, that will be loaded up to 330 MWs. He
submitted that the Committee has ignored these aspects. REL had pointed out
these considerations to the Committee, and that has been acknowledged in the
Report. Shri. Cooper further submitted that since the premier technical agency
(i.e. CEA) had made certain recommendations with regard to the criteria and
factors to be considered, these should have been used in judging whether or not
there is surplus capacity. REL Counsel
urged that the Report not be considered as it is, and that the Committee be asked to re-consider its findings
keeping in mind the technical guidelines set out by the CEA. Shri. Cooper
further submitted that surplus capacity to the extent of at least 100 MWs could
be provided straight away as against 800 MWs asked for, in case the Commission
comes to the view that 800 MW is not capable of being transmitted through the
open access regime in these circumstances.
25. Shri. Cooper submitted that, apart from
line length, the current carrying capacity has also to be taken into account.
However the Report is silent on this aspect and proceeds solely on the basis of
SIL. Moreover, the Committee totally ignored the fact that the flow of current
also moves in the reverse direction. There is an interchange of supply of
energy between TPC and MSEB, and the surplus capacity is to be assessed only
after taking into account the reverse flow.
26. REL Counsel also drew attention to the
provisions of EA, 2003, which requires the unbundling of integrated utilities.
He quoted Section 2 (47) of the EA, 2003, which reads as follows:
"open
access" means the non-discriminatory provision for the use of transmission
lines or distribution system or associated facilities with such lines or system
by any licensee or consumer or a person engaged in generation in accordance
with the regulations specified by the Appropriate Commission."
He submitted that a non-discriminatory provision has
a definite meaning and definite purpose. This is made further clear by Section
39, which provides that the function of the State Transmission Utility shall be
:
"(d) to
provide non-discriminatory open access to its transmission system for use by
(i) any licensee or generating company
on payment of the transmission charges."
Here also the emphasis is on the word
non-discriminatory. Otherwise, there is
an inherent tendency on the part of an integrated undertaking to make available
its lines only for the purposes of its own generation. The open access regime has implications for
cheapest energy sourcing, particularly when coupled with the unbundling
provisions. Thus, while assessing
whether or not there is surplus capacity available, the principle of non-discriminatory
access must also be borne in mind by the Commission or Committee. Shri. Cooper submitted that load growth is
taking place which will be catered to by the existing transmission lines, and
queried as to why REL should be denied access on a non-discriminatory basis for
catering to that increased load.
Transmission line owners do not get preference on their own lines.
27. To a query from the Commission, Counsel
admitted that REL had a representative on the Committee and that he had urged
that the line loading as a function of length has to be considered, as recorded
at page 14 of the report :
"REL
representative stated that line loading as a function of length as per CEA
guidelines should be considered.
However, the rest of the Committee Member stated that contingency should
also be considered as per the CEA guidelines.
In the present case, the contingency of 220 KV Kalwa Salcette D/c line
was considered which resulted in overloading beyond capacity. Hence, other contingencies like shipping
etc. was not considered."
In effect, however, other members were looking at
the contingency of what happens when one unit shuts down. However, that cannot be the basis, or else
open access can never be provided.
28. To the Commission's query regarding CEA
guidelines on redundancy, Shri. Barbole, CE (LDC) and others of MSEB stated
that these guidelines are given in the CEA Manual at 6.2 which deals with how
certain contingencies are to be taken into account :
"As a general rule, the EHV grid system
shall be capable of withstanding without necessitating load shedding or
rescheduling of generation, the following contingencies…"
When one line is already out and some other line
also trips, the system should be able to withstand it. Considering this
guideline, MSEB's network is just sufficient for their own requirement. He also pointed out that the Committee
included independent outside experts.
Non-discriminatory open access does not mean compulsion regardless of the
circumstances.
29. Counsel for REL submitted that, although
the REL representative had signed the report in his capacity as a member of the
Committee, that could not be construed as his accepting the conclusions. In any
case, it is for the Commission to decide whether the Report should be accepted
or not.
30. Shri. Cooper further stated that, as far
as TPC is concerned, to the extent that REL's power is transmitted on those
lines, it would be to take care of a demand which is being catered to currently
by TPC. Therefore, to the extent that REL transmits more, it will only mean that
there will be a corresponding reduction in the transmission by TPC. There will be no over loading so far as
TPC's lines are concerned. Another factor which has been overlooked is the
question of load growth. Even today, as per MSEB, there is no surplus capacity
and the system is incapable of taking it, and yet the load growth is being
serviced through their transmission lines, which are allegedly deficient in
catering to the supply. If the load
growth can be met from the existing transmission lines, he queried as to why
MSEB are not making available surplus capacity to other parties.
31. MSEB representatives stated that the
contention of REL that MSEB will be meeting their own load growth on the
existing system is wrong. He clarified that for their future load growth, MSEB
are planning for strengthening and additional infrastructure. The Commission queried as to the time frame
for increasing capacity so that open access can be provided in future, and
observed that transmission access is open from day one. As STU, MSEB had to plan for these things
well in advance and recover the cost through their ARR, and pointed out that
similar issues had come up in the wind energy matter also. MSEB representatives submitted that the
current loading is given in the Report, and that infrastructure addition and
strengthening is undertaken based on demand from consumers. In this above context, the Commission
referred to the earlier RoP (para 11) in which mention has been made of MSEB's
plans. The Commission directed that
MSEB should file their plans for adding and strengthening transmission capacity
with full details and time-frame so that the extent and phasing of actual
provision of open access becomes clear.
32. Shri. J.D. Kulkarni of TPC, referring to
page 14 of the Report, submitted that the Committee has properly observed that
:
"As the power flow on the gateway to TPC
system is itself beyond the capacity, the question of evaluating transmission
capacity in TPC was not done. The SIL
loading was taken as 132 MW as per CEA guidelines. REL representative stated that line loading as a function of
length, as per CEA guidelines should be considered. However, the rest of the Committee members stated that
contingencies should also be considered as per CEA guidelines. In the present case the contingency of one
of the 220 kV Kalwa-Salsette D/c line being out was considered which resulted
in overloading beyond capacity. Hence
other contingencies like tripping of one 500 MW unit etc. were not considered
as they are more severe than the line contingency".
Tarapur Boisar is a long line. Thus, the Committee
had found that even without any
contingency such as a generating unit tripping, the load demanded is not
possible. Shri. Kulkarni further submitted that all this was explained in
Committee to REL.
33. Shri. Kulkarni of TPC further stated
that, as regards the flow of current, REL are bringing power from outside and
TPC are drawing from the grid. The power flow on the interconnection would be
whatever power REL will be bringing from outside even without considering a
single contingency. He pointed out that the Committee had also stated that the
contingency should also be considered as per the CEA guidelines. He submitted
that in case TPC do not back down, then a lesser quantum is going to flow on
the interconnection. While conducting the study, the Committee has not
considered full backing down by TPC. In fact the Committee has considered that
TPC will also be selling about 300 to 400 MW outside. Shri. Kulkarni further stated
that there is absolutely no margin available on the interconnection. Moreover, on the Tarapur-Boisar line, MSEB
said that it is not possible to bring additional power. It would bring the
nuclear power unit itself into danger.
He also pointed out that, according to the Report, access could possibly
be provided, but to the limited extent of 50 - 100 MW, and that no dissent note
had been added by the REL representative.
