gas billing
TRANSCRIPT
SAP ISU BILLINGSAP ISU BILLING
(Gas division)(Gas division)
Gas Industry
Gas distribution
General context of IS-U (Gas) Billing
GenCoGenCo RetailerRetailerTransCo
DisCo
Segments in a deregulated scenario
Present IS-U Billing is focused on DisCos
Present Gas Billing meets standard demands of utilities with flexible integration of additional demands
Enabling of deregulated scenarios in preparation for division electricity
Requests for Gas Billing regarding: deregulated scenario, i.e.: producers, pipelines and utilities
integration of special needs of North American gas companies
Gas billing
Background of present gas billing Legal prerequirements
• DVGW • German association analogous to the American AGA• deals with problems of division G(as) and W(ater)
• Report G685 • comparable to special AGA reports • provides rules for standard gas billing of mainly residential and commercial
customers• requirements are largely met by IS-U gas billing
•Report G486• provides rules for billing of large industrial customers • takes into account special features such as the use of the GERG virial equation• requirements up to now can only partly be met by integrating calculations deduced from other non-SAP-systems
Central Gas factors
Volume correction factor
Calorific value
Application determined by IS-U billing type:
volumetricno conversion of meter reading difference
standard volumetricone conversion via volume correction factor
thermal two conversions via volume correction factor and calorific value
Gas Procedures
Technical description of a register includes especially
Nominal load
Pressure measured at the register (gauge pressure)
Inclusion of factors provided by the register register does not integrate any thermal gas factors
register integrates temperature
register integrates temperature and pressure
register integrates temperature, pressure and compressibility
Thermal gas billing
Gas Procedures Technical description gives rise to possible choice of
gas procedures when installing a register
Gas procedure contains all necessary information for computing the gas factors, i.e. volume correction factor and calorific value
Gas procedure is broken down into two procedures describing the computation of the central gas factors, more precisely:
Gas procedure =
( volume correction factor procedure , Calorific value procedure )
Volume correction factor procedure
The volume correction factor VCF is defined as:Ratio of norm volume to operating volume
Basic explicit formula for volume correction factor VCF derived from the ideal gas law is as follows:
Tn Pamb + Peff 1VCF = ———— • —————— • ——
To + t Pn K
Volume Correction Procedure Tn = Standard Temperature (Kelvin or Rankine)
To = Zero Point of temperature scale(273.15 Kelvin or 460 Rankine)
t = Temperature in Celsius or Fahrenheit
Pamb = Air Pressure
Peff = Measured Pressure at the register
Pn = Standard Pressure (e.g. 1.01325 bar)
K = Gas Law Deviation Factor
F = 1 / K with F = Supercompressibility Factor
Dimensions
Gas Billing possible in SI system ( metric system )
English system ( non-metric system )
General Notion of Dimension Class of measurement units belonging to physical quantity, e.g.
volume or energy (cf, Ccf, Mcf )
Usually fixed conversion factors between units within the same dimension, e.g. Ccf <-> Mcf or kWh <-> MWh
Mapping into SAP system via general Implementation Guide
applicable for all divisions i.e. not Gas specific
Dimensions Conversion by central gas factors
Conversion of units of measurement belonging to different dimensions
e.g. Ccf -> Btu ( English system )
e.g. m3 -> kWh ( SI system )
Conversion by Volume Correction Factor VCF
Operating volume * VCF = standard volume
source measurement unit, e.g. cf or m3
target measurement unit, e.g. Scf or Nm3
Define source / target unit in Volume Correction Procedure
Volume Correction Procedure defines rule for computing VCF, which in general is NOT a fixed factor
Dimensions Conversion by Calorific Value CV
Standard volume * CV = Energy (billing consumption)
source measurement unit, e.g. scf or Nm3
target measurement unit, e.g. Btu or kWh
Define source / target unit in Calorific Value Procedure
Calorific Value Procedure defines rule for computing CV, which in general is NOT a fixed factor
Dimensions
Overview of all conversions Meter Difference [ meter reading unit ]
[ meter read. unit -> source unit VCF ]
* VCF [ source unit VCF -> target unit VCF ]
[ target unit VCF - > source unit CV ]
* CV [ source unit CV -> target unit CV ]
[ target unit CV -> billing unit ]
= Energy [ billing unit ]
Components of Volume Correction Factor
Gas Temperature
Air pressure
Gas pressure at the meter
Gas Law Deviation Factor per pressure and temperature
per register
Components of Volume Correction Factor
Application of components determined by
“Inclusion of Factors”
Register includes no components
Register includes temperature
Register includes temperature and pressure
Register includes temperature, pressure and compressibility
Tn Pamb + Peff 1VCF = ——— • ——————— • ——
To + t Pn K
Temperature
Determination of Temperature
Temperature
V_TE307
Temperature area
V_TE447Monthly MeasuredGas Temperature
V_TE247
Fixed Temperature
V_TE551Fixed Temperature
Key
Daily baseMonthly base
Temperature Procedures V_TE447 (monthly base) used for calculation of:
Arithmetical annual average
Weighted annual average
Arithmetical average over the billing period
Weighted average over the billing period
V_TE247 (daily base) used for determination of:
Fixed temperature
Daily base
monthly base
Determination of Pressure
Tn Pamb + Peff 1VCF = ——— • ——————— • —
To + t Pn K
Pressure
Air Pressure ( Pamb )
V_TE309
Air Pressure area
V_TE339Monthly Measured
Air Pressure
V_TE907Annual
Air pressure
Monthly base „Daily“ base
Air Pressure Procedures
V_TE907 (daily base) used for calculation of:
Annual air pressure
V_TE339 (monhtly base) used for calculation of :
Arithmetical average over the billing period
Weighted average over the billing period
Monthly measured air pressure
Gas pressure at the meter (Peff)
V_TE341
Measured Pressure
V_TE445Gas Law Deviation Factor per Pressure
and Temperature
V_TE345Gas Pressure
Area
Permitted pressures assigned to the register or indirectly via pressure regulator during installation
No explicit calculation of GLDF
Default pressure depending on regional structure Correction pressure at the meter is possible
Compressibility factor Z = deviating behavior of real gas in comparison to ideal gas p*V = Z*R*T
Gas Law Deviation Factor K = Z/Zn = ratio of compressibility factors at any condition to those at normal conditions F = 1 / K with F = Supercompressibility Factor
very complicated to determine
AGANX-19-mod
GERG88
no explicit calculation in IS-U; values must be imported from non-SAP-system
Gas Law Deviation Factor
Special Volume Correction Factor Procedures
Fixed volume correction factor no use of formula derived from ideal gas law
factor dependent on:
V_TE929
Billing class
Air pressure area
Temperature area
Daily base
Calorific value
V_TE453
Calorific ValueDistricts
V_TE921Energy FeedingAccording to
Calorific Value District
V_TE449Monthly
Calorific Value
Calorific Value Procedures
V_TE449 ( monthly base ) used for calculation of:
Arithmetical annual average
Weighted annual average
Arithmetical average over the billing period
Weighted average over the billing period
determination of monthly calorific value
Calorific Value Procedures Determination of CV for Billing
based on V_TE449 (monthly values)
maintained by customizing transaction EA70
comparison of (weighted averages ) via V_TE449 with pre-set fixed calorific value is possible
User decides on billing calorific value and maintains it
Example: =======07/98 Actual average Fixed value Delta - > Bill CV
11.01 11 0.01 11
Customizing Transactions
EA70
Billing Calorific Value
EA76
Calorific Value procedure
EA79
Volume correction factor procedure
EA73
Gas procedure
Connecting data relationships Register
Inclusion of factors
Gas procedure
Regional structureproposes values during device installation for the following:
Air pressure area
Gas Pressure Area
Temperature Area
Calorific value district
Rate category (defined in installation) Type of Gas Billing ( thermal, standard volumetric, volumetric )
Connecting data relationships
Inclusion of factors (P)
nominal load (P) gas pressure at the meter (P) Gas procedure Air pressure area Gas Pressure Area Temperature Area Calorific value district
Installation
Rate category
Type of gas billing (P)
Billing class (P)
Execution of Gas procedure during
billing
meter reading
simulation
budget billing plan extrapolation
P = proposal for gas procedure
Installation
Register Data and Rate Category
Connecting data relationshipsGas Procedure Calorific value procedure V_TE449 (monthly)
Volume correction procedure
Temperature
V_TE247 fixed (daily)
V_TE447 (monthly)
Air pressure
V_TE339 (monthly)
V_TE907 (daily)
Gauge pressure
V_TE341 („daily“)
V_TE345 (daily)
GLDF
V_TE445
register („daily“)
Special VCF procedures
fixed VCF (daily)
register relationship
ZZ
ZE