Technical Rule Code of Practice G 685 November 2008

Transcription

1 Regelwerk Technical Rule Code of Practice G 685 November 2008 Gas Billing

2 Warning This English-language version is an informal translation from the German original. However, only the original German-language version has been exclusively authorised by the DVGW and its Technical Bodies. The DVGW reserves the right to revise this version at any time due to possible translation errors. Anybody is free to use the DVGW system of rules. Users are responsible for the proper use of the DVGW system of rules in each individual case. ISSN Pricegroup: 11 DVGW, Bonn, November 2008 DVGW German Technical and Scientific Association for Gas and Water e. V.; Technical-Scientific Association Josef-Wirmer-Straße 1 3 D Bonn/Germany Phone: Fax: info@dvgw.de Internet: Reprint and photomechanical reproduction, also of excerpts, is only permitted with the approval of the DVGW e. V., Bonn. Distribution: Wirtschafts- und Verlagsgesellschaft Gas und Wasser mbh, Josef-Wirmer-Str. 3, Bonn Phone: Fax: info@wvgw.de Internet: Item No.:

3 Gas Billing Regelwerk Content Foreword Scope Normative references Legislation Ordinances European Standards National Standards Technical Rules Other Technical Rules Terms, symbols, units and abbreviations Billing CV H s,eff Metered readings and data relevant for gas billing Billing temperature T eff Billing volume Billing cycle Flowing conditions Calorific value H s Working pressure p eff Delivered calorific value Substitute value Faulty reading Gas supply grid Degree day number Gt Compressibility factor K Ultimate consumer Supplier Atmospheric pressure p amb Standard pressure p n Standard temperature T n Standard condition Compression factor Z p,t Arithmetic value Reference date Daily mean temperature t d Thermal energy E Thermal output P

4 3.27 Shipper Volume at flowing conditions V b Volume at standard conditions V n Steam partial pressure p H2O Volumetric correction factor z Determination of thermal energy and thermal output Fundamental principles Methods Authorised personnel Determination of billing volume Determination of volume at standard conditions V n Variables for determining volume at standard conditions V n General Volume at flowing conditions V b Volumetric correction factor z Standard temperature T n Billing temperature T eff Atmospheric pressure p amb Working pressure p eff Standard pressure p n Compressibility factor K Steam partial pressure p H2O Determination of delivered and billing CVs General fundamentals Determination of delivered calorific values Calorific value per hour Daily delivered calorific value and delivered calorific value in the course of 24 hours Arithmetically averaged daily delivered calorific value and delivered calorific value in the course of 24 hours Volume-weighted daily delivered calorific value and delivered calorific value in the course of 24 hours Monthly delivered calorific value and delivered calorific value in the course of one month Arithmetically averaged monthly delivered calorific value and delivered calorific value in the course of one month Volume-weighted monthly delivered calorific value and delivered calorific value in the course of one month Annual delivered calorific value and delivered calorific value in the course of 12 months Delivered calorific value for mixed gases at one entry point Determination of billing CV Billing CV for single-site input Billing CV for multiple-site input Calorific value allocation method Quantity balancing method Identification method Mean value method Monthly billing CVs and billing CVs in the course of one month Annual billing CV and billing CVs in the course of 24 months Mean value method for cascadic grids Deviations

5 7 Calculation of substitute values General Causes Methods Permissible frequency Obligations Billing Documentation Quantity allocation over one billing cycle General Meter reading Allocation method Linear allocation Consumption-dependent allocation Temperature-dependent allocation Determination of daily mean temperatures and degree day numbers Allocation by degree day numbers Allocation by standard demand profiles General Domestic customers Commercial customers Calculation of partial sums Obligations Invoicing Documentation Meter readout by 31 st December General Method Obligations Invoicing Documentation Invoicing requirements Documentation requirements Documentation requirements on energy determination Billing CV Volume at standard conditions Calculated thermal energy/thermal output Documentation of readout by 31st December Documentation of the substitute value calculation method Documentation of the quantity allocation method over the billing cycle Market roles Interim regulations

6 Annex A Examples and explanations...45 A.1 Determination of atmospheric pressure examples...45 A.2 Example illustrating the determination of billing CV for two entry points with gases of different qualities, using the mean value method...50 A.3 Energy calculation example...51 A.4 Technical installation for monthly ultimate consumer invoicing...52 A.5 Annual ultimate consumer invoice example...53 A.6 Verification of non-infringement of the 2 %-limit for multiple-entry point injection...54 A.7 Quantity balancing method example...56 A.8 Identification method example...58 Annex B Charging Areas...63 Literary references

7 Foreword This Code of Practice was created by the Technical Committee on Gas Metering and Billing. It defines the procedures to be followed when determining data used for the billing of gases described in DVGW Code of Practice G 260 Gas Composition. Gas Billing was created after Technical Rule Thermal Gas Billing was introduced in 1968 (1 st edition), and evolved from two follow-up editions in 1981 and 1993 with a number of addenda and DVGW circulars. The methods to determine data for gas billing have been adjusted to reflect the latest relevant state of the art, in keeping with technological progress. This fourth edition includes three addenda to complement the April 1993 DVGW Code of Practice, as follows: 1 st addendum: Determination of thermal output 2nd addendum: Quantity allocation within one billing cycle 3rd addendum: Substitution of gas data relevant for billing The monitoring activities carried out by the weights and measures authorities at the utilities to verify the implementation of for gas billing purposes revealed a need for an editorial review of the Code of Practice. The reasons for publishing a 4 th edition of this Code of Practice were the necessity to eliminate obsolete parts, integrate circulars and addenda, and improve the readability of the Code of Practice. This Code of Practice was reviewed by the DVGW Technical Committee (TC) on Gas Metering and Bil ling in cooperation with the weights and measures offices of the Federal states and the Physikalisch- Technische Bundesanstalt (National Metrology Institute). This Code of Practice supersedes : ; the 1 st addendum: to G 685; the 2 nd addendum: to G685 and the 3 rd addendum: to G

8 Amendments The following amendments have been made compared to :1993: a) Editorial adaptation of the Code of Practice b) Integration of circulars and addenda c) Improvement of the readability of this Code of Practice d) Review of facts and circumstances relevant for billing Earlier editions :1968 :1983 : st addendum 1995 to 2 nd addendum 2004 to 3 rd addendum 2004 to 08