Fri. Sep 24th, 2021

City gas distribution

Transporting future fuel

#78 Natural gas parameter & measurement as per PNGRB Guidelines

9 min read

Gas Parameters

1. The authorized entity shall formulate the calorific value (CV) band for the natural gas to be transported through natural gas pipeline keeping in view the following parameters, namely:-

  1. CV of its own natural gas proposed to be transported;
  2. CV of firmed up contracted capacity of natural gas;
  3. requirements of downstream consumers of natural gas on the pipeline;
  4. technical requirement of the pipe line system; and
  5. CV band of the inter-state pipelines either supplying natural gas into the pipeline system or receiving natural gas from this pipeline system.

2. The transporter shall publish CV band referred to in sub-regulation (1) on its website within a period of one month of authorization by the Board, as referred to in sub-regulation (2) of regulation 3, under intimation to the Board.

Provided that the entities authorized before the publication of these regulations shall publish the CV band within a period of one month of the date of publication of these regulations.

3. CV band as referred in point 1 shall be applicable to all shippers on nondiscriminatory basis.

4. The transporter may review the CV band for natural gas from time to time taking into account new major source of gas supplies or new consumers: Provided that CV band so updated shall not adversely affect any of the existing shippers:
Provided further that transporter shall immediately inform the Board as and when such updating is carried out by the transporter besides putting the same on its web site.

5. The threshold limits for other elements in natural gas like CO2, CO, H2S, N2, O2, water dew point, hydrocarbon dew point, etc. shall be as given in table below;

6. The transporter shall define the gas parameters at entry points in terms of gas hydraulics specifying the acceptable range of pressure and temperature and the same shall be hosted on the website of the transporter.

7. Shipper shall supply gas conforming to all parameters specified in sub-regulations (1), (4) to (6) and the transporter shall deliver gas at exit point conforming to parameters of gas as specified in sub-regulations (1), (4) and (5). Provided that the pressure and temperature shall be as per the contract between shipper and the transporter.

Measurement of Gas

Before knowing the norms for measurement of gas, we must known the facilities required at entry point & exit point. It is explained in the following points;

  1. Shipper shall arrange to deliver gas at entry point on the pipeline system and shall provide all facilities, including measuring equipment, required for transfer of custody and delivery of gas to the transporter unless otherwise agreed to between shipper and transporter.
  2. Transporter shall execute hooking up facility of shipper to the entry point at the cost of shipper.
  3. Shipper or his authorized nominee shall own, operate and maintain facilities upstream of entry points at his own cost and risk unless the facilities are provided by the transporter under a separate contract.
  4. The transporter shall own and operate facilities including measuring equipment at exit point for transfer of custody and delivery of gas to the shipper unless otherwise agreed to between shipper and transporter and the exit point gas parameters shall be mutually agreed to between shipper and transporter.
  5. The transporter shall execute, at the cost of shipper, the facility of hooking up of shipper facility with that of transporter at exit point.
  6. The shipper shall provide space and cooperate with the transporter in installing, operating, maintaining and modifying any specific exit point facilities when such exit point facilities are provided in the premises of the shipper.
  7. The shipper may provide check meter, conforming to the applicable standard and specifications, at the delivery point in natural gas pipeline: Provided that in case of any variation in the readings in the meter of transporter and shipper, the reading of the transporter meter shall be taken as final.
  8. In case of any dispute in metering, the meter proving or certification shall be carried out by an accredited third party as approved by the Board.
  9. In case of any fault in the meter of transporter, the expenses on this account shall be borne by the transporter and in case no fault is found in the meter, the expenses shall be borne by the shipper.

Measurement of gas;

  1. The transporter shall ensure the provision of the entry and exit point equipment to measure gas composition, calorific value, pressure and temperature on continuous basis as specified in the points mentioned above..
  2. The transporter shall divide the natural gas pipeline into a number of “a homogenous area” (AHA) and shall continuously measure the quality parameters by Gas Chromatograph (GC) in each AHA. Here, “a homogeneous area” (AHA) means a part of the pipeline within which the gas of similar specifications including calorific value is received or delivered over a specified time period;
  3. Measurement of CV and gas quality as provided in points above shall be sufficient for billing and other contractual purposes for all exit points served by the AHA.
  4. Total error limit and accuracy of the measuring equipment shall be as agreed to between the entities subject to any mandatory specifications, if any, laid down by the Board through regulations.
  5. The transporter shall carry out verification, calibration or proving of measuring equipment as per the relevant codes and standards.
  6. Either shipper or transporter may install check meters at requisite points with a precondition so as not to interfere with the measurement equipment installed by the entity for custody transfer purpose.
  7. Gas accounting shall be done on daily basis and the gas reconciliation, billing & other terms shall be as decided between the entities.

Also, here we need to discuss certain obligations at entry point & exit point,

  1. At the entry point when the shipper delivers natural gas that does not meet the quality requirements as specified in Gas parameter point number (1), (4) to (6), in respect of CV band and threshold level of other elements of gas, the transporter may-
    (a) refuse to accept it; or
    (b) accept any gas that does not meet the requirements of gas in terms of gas parameters

(i) as specified in the table above:

Provided that transporter may charge reasonable cost of service from the shipper, as may be mutually agreed, for any additional facilities or
treatment for cleaning up or integrity requirements of the pipeline and
to upgrade gas to pipeline specifications;

Provided further that such off-spec natural gas does not adversely
affect the existing customers’ quality specifications committed by the
transporter at the exit points;

(ii) as specified in Gas Parameter point number (1) and (4):
Provided that the transporter may charge the reasonable cost of service
for the capacity adjustment from the shipper for transportation of such
gas and for capacity constraints in the system:
Provided further that such off-spec natural gas does not adversely affect
the existing customers’ quality specifications committed by the
transporter at the exit points.

  1. At the exit point when the transporter delivers gas that does not meet the quality requirements as specified in Gas Parameter point number 7, the shipper may –
    (a) refuse to accept delivery and in such a case the transporter shall be liable to pay liquidated damages to the shipper as per their terms of contract; or
    (b) accept the gas and in such case no charges shall be payable by transporter.

Also note that, “off-spec natural gas” means the natural gas which does not conform to the parameters specified at Gas Parameter point number (1), (4), (5) and (6).

Leave a Reply

Your email address will not be published. Required fields are marked *

Copyright © Citygasdistribution |All rights reserved |