BILLINGIRPARTSURPLUSSUM

BILLINGIRPARTSURPLUSSUM supports the Settlements Residue Auction, by showing the weekly billing SRA distribution and associated fees to Auction participants.

BILLINGIRPARTSURPLUSSUM data is confidential to the relevant participant.

Source

BILLINGIRPARTSURPLUSSUM is populated by the posting of a billing run where the participant has purchased auction units relating to that billing run.

Volume

An indicative maximum is 16 records inserted per billing run, or 166 records inserted per week.

Column Schema

BILLRUNNO

The sequential number of a billing run

SQL Type: NUMBER(3,0) Polars Type: pl.UInt16

This column is mandatory, and a primary key.

CONTRACTYEAR

SRA Contracted Year (calendar year)

SQL Type: NUMBER(4,0) Polars Type: pl.UInt16

This column is mandatory, and a primary key.

FROMREGIONID

Nominated source region for Interconnector

For more information, see the dedicated documentation page.

The SQL type is VARCHAR2(10). This is actually a factor/enum, with values:

• QLD1

• VIC1

• TAS1

• NSW1

• SA1

This column is mandatory, and a primary key.

INTERCONNECTORID

Contracted Interconnector

SQL Type: VARCHAR2(10) Polars Type: pl.Categorical

This column is mandatory, and a primary key.

PARTICIPANTID

Unique participant identifier

For more information, see the dedicated documentation page.

SQL Type: VARCHAR2(10) Polars Type: pl.Categorical

This column is mandatory, and a primary key.

QUARTER

Residue Contract Quarter

SQL Type: NUMBER(2,0) Polars Type: pl.Int8

This column is mandatory, and a primary key.

RESIDUEYEAR

Year of the Residue Contract; may differ from the calendar year at week 1.

SQL Type: NUMBER(4,0) Polars Type: pl.Int16

This column is mandatory, and a primary key.

WEEKNO

Week no within the contract year. Week no 1 is the week containing 1st January

Warning

There may be 53 weeks in a year, depending on how weeks align to the year start/end.

SQL Type: NUMBER(3,0) Polars Type: pl.UInt16

This column is mandatory, and a primary key.

ACTUALPAYMENT

Net payment to participant, including auction fees

SQL Type: NUMBER(15,5) Polars Type: pl.Float64

This column is not mandatory.

AUCTIONFEES

Total auction fees payable in this week (negative amount). If AUCTIONFEES + AUCTIONFEES_GST >= TOTALSURPLUS then ACTUALPAYMENT is zero.

SQL Type: NUMBER(15,5) Polars Type: pl.Float64

This column is not mandatory.

AUCTIONFEES_GST

The GST amount on the auction fees, always being zero.

SQL Type: NUMBER(15,5) Polars Type: pl.Float64

This column is not mandatory.

AUCTIONFEES_TOTALGROSS_ADJ

The adjusted total Auction fees for the Directional Interconnector. Calculated as the amount of the total fees due from the SRA Auction Participant, pro-rated based on the total surplus for each Directional Interconnector the SRA Auction Participant contracted.

SQL Type: NUMBER(18,8) Polars Type: pl.Float64

This column is not mandatory.

CSP_DEROGATION_AMOUNT

The CSP derogation amount applied as an adjustment to SRA.

SQL Type: NUMBER(18,8) Polars Type: pl.Float64

This column is not mandatory.

LASTCHANGED

Date and time this record was last modified

For more information, see the dedicated documentation page.

SQL Type: DATE Polars Type: pl.Datetime()

This column is not mandatory.

Example: 2026/01/20 00:05:00

TOTALSURPLUS

Total residue amount allocated to participant

SQL Type: NUMBER(15,5) Polars Type: pl.Float64

This column is not mandatory.

UNADJUSTED_IRSR

The SRA amount unadjusted by CSP.

SQL Type: NUMBER(18,8) Polars Type: pl.Float64

This column is not mandatory.

New Data Timing

Posting of a billing run

Code Examples

Polars

Casting is enums, categoricals etc is not essential, but may speed up parsing. Swapping int for pl.UInt16, pl.Int32 would also speed up parsing. However some of the datatypes are inferred, so they may be wrong.

This code deduplicates for you. Deduplication is normally only required across multiple months.

This code assumes that all columns are present, which may not be true for older files.

import polars as pl
import polars.selectors as cs

# e.g. "2029/03/15 00:05:00"
dt_s_fmt = "%Y/%m/%d %H:%M:%S"

csv_paths = ["SOMEFILE.CSV", "OTHERFILE.CSV"]

lf = (
    pl.concat(
        [
            pl.scan_csv(
                csv_path,  # must be unzipped beforehand
                skip_rows=1,  # skip the header
                infer_schema=False,  # much faster
            )
            .filter(cs.by_index(0) == "D")  # drop the footer
            .select(~cs.by_index(range(4)))  # drop metadata columns
            for csv_path in csv_paths
        ],
        how="diagonal_relaxed",
    )
    .with_columns(
        pl.col("LASTCHANGED").str.strptime(pl.Datetime, dt_s_fmt),
    )
    .cast(
        {
            "BILLRUNNO": int,  # or pl.UInt16
            "CONTRACTYEAR": int,  # or pl.UInt16
            "FROMREGIONID": pl.Enum(["QLD1", "VIC1", "TAS1", "NSW1", "SA1"]),
            "INTERCONNECTORID": pl.Categorical,
            "PARTICIPANTID": pl.Categorical,
            "QUARTER": int,  # or pl.Int8
            "RESIDUEYEAR": int,  # or pl.Int16
            "WEEKNO": int,  # or pl.UInt16
            "ACTUALPAYMENT": pl.Float64,
            "AUCTIONFEES": pl.Float64,
            "AUCTIONFEES_GST": pl.Float64,
            "AUCTIONFEES_TOTALGROSS_ADJ": pl.Float64,
            "CSP_DEROGATION_AMOUNT": pl.Float64,
            "TOTALSURPLUS": pl.Float64,
            "UNADJUSTED_IRSR": pl.Float64,
        }
    )
    # Deduplicate
    # We want one row per ['BILLRUNNO', 'CONTRACTYEAR', 'FROMREGIONID', 'INTERCONNECTORID', 'PARTICIPANTID', 'QUARTER', 'RESIDUEYEAR', 'WEEKNO']
    # Tie-breaker: greatest value of ['RESIDUEYEAR', 'QUARTER']
    .sort(["RESIDUEYEAR", "QUARTER"], descending=False)
    .unique(
        subset=[
            "BILLRUNNO",
            "CONTRACTYEAR",
            "FROMREGIONID",
            "INTERCONNECTORID",
            "PARTICIPANTID",
            "QUARTER",
            "RESIDUEYEAR",
            "WEEKNO",
        ],
        keep="last",
    )
)

Nemosis

This table is not yet available in Nemosis.

Availability

Visibility: Private

This table is not available in the public monthly MMSDM archive. Is is only available to registered market participants over FTP inside a VPN.

Deduplication and PDR Loader Configuration

The primary keys are:

• BILLRUNNO

• CONTRACTYEAR

• FROMREGIONID

• INTERCONNECTORID

• PARTICIPANTID

• QUARTER

• RESIDUEYEAR

• WEEKNO

The transaction type is "insert", which means that you will usually not see duplicate data. If you do, you can deduplicate based on the primary keys, without sorting first. Rows from different files with the same primary keys should have the same values.

PDR Loader configuration is:

Report Name	Report Subtype	Version
BILLING	IRPARTSURPLUSSUM	7

This means that the CSV files start with metadata columns:

I,BILLING,IRPARTSURPLUSSUM,7,...
D,BILLING,IRPARTSURPLUSSUM,7,...

Indexes

There is more than one index.

Index 1:

• RESIDUEYEAR

• QUARTER

Index 2:

• LASTCHANGED

Links

This page as JSON (schema documented here, but may change)

Download a JSON Schema specification for this table.

Official AEMO schema documentation

Other Information

Package: BILLING_RUN

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