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Ancillary Service Trade (AST)

Ancillary Service Trade (AST)

An Ancillary Service Trade is used to describe a scheduled trade of ancillary services between a buyer and a seller. The following diagram describes the structure of an Ancillary Service Trade (ASTrade):

ASTrade Structure

The ASSchedule structure is based upon a TmSchedule as described previously in this document. The submission of an ASTrade (or generally any trade) requires a matching trade to be submitted by the counter party before the close of the market. On submission, the following table describes the items used for an ASTrade:

Element Req? Datatype Description Values
startTime K dateTime Start time for bid Valid start hour boundary for trade date
endTime K dateTime End time for bid Valid end hour boundary for trade date
externalId N string External ID QSE supplied
asType K string Ancillary service type

Non-Spin

NSPNM

Reg-Down

Reg-Up

RRSUF

RRSPF

RRSFF

ECRSS

ECRSM
buyer K string Trade buyer Valid QSE
seller K string Trade seller Valid QSE
otherPartySubmitted N Boolean

For querying purposes only:

True if trade was entered by other party

true (default)

or false
tradeID N string reserved for future use
ASSchedule/startTime N dateTime not used not used
ASSchedule/endTime N dateTime not used not used

ASSchedule/

TmPoint/time

 Y dateTime Absolute time for beginning of interval Valid time within the trading date

ASSchedule/

TmPoint/ending

 N dateTime Absolute time for end of interval Valid time within the trading date

ASSchedule/

TmPoint/value1

 Y float Megawatts >= 0

The following is an XML example for an ASTrade:

<BidSet xmlns="http://www.ercot.com/schema/2007-06/nodal/ews" xmlns:ns2="http://www.ercot.com/schema/2007-06/nodal/ews">
    <tradingDate>2022-01-12</tradingDate>
    <ASTrade>
        <startTime>2022-01-12T00:00:00-06:00</startTime>
        <endTime>2022-01-12T08:00:00-06:00</endTime>
        <externalId>123456</externalId>
        <buyer>QSAMP2</buyer>
        <seller>QSAMP1</seller>
        <asType>Non-Spin</asType>
        <ASSchedule>
            <TmPoint>
                <time>2022-01-12T00:00:00-06:00</time>
                <ending>2022-01-12T06:00:00-06:00</ending>
                <value1>38.0</value1>
            </TmPoint>
            <TmPoint>
                <time>2022-01-12T06:00:00-06:00</time>
                <ending>2022-01-12T08:00:00-06:00</ending>
                <value1>35.0</value1>
            </TmPoint>
        </ASSchedule>
    </ASTrade>
    <ASTrade>
        <startTime>2022-01-12T00:00:00-06:00</startTime>
        <endTime>2022-01-12T03:00:00-06:00</endTime>
        <externalId>123457</externalId>
        <buyer>QSAMP3</buyer>
        <seller>QSAMP1</seller>
        <asType>NSPNM</asType>
        <ASSchedule>
            <TmPoint>
                <time>2022-01-12T00:00:00-06:00</time>
                <ending>2022-01-12T03:00:00-06:00</ending>
                <value1>41.0</value1>
            </TmPoint>
        </ASSchedule>
    </ASTrade>
    <ASTrade>
        <startTime>2022-01-12T00:00:00-06:00</startTime>
        <endTime>2022-01-12T01:00:00-06:00</endTime>
        <buyer>QSAMP1</buyer>
        <seller>QSAMP2</seller>
        <otherPartySubmitted>false</otherPartySubmitted>
        <asType>RRSPF</asType>
        <ASSchedule>
            <TmPoint>
                <time>2021-11-02T00:00:00.000-05:00</time>
                <ending>2021-11-02T01:00:00.000-05:00</ending>
                <value1>22</value1>
            </TmPoint>
        </ASSchedule>
    </ASTrade>
    <ASTrade>
        <startTime>2022-01-12T00:00:00-06:00</startTime>
        <endTime>2022-01-12T01:00:00-06:00</endTime>
        <buyer>QSAMP1</buyer>
        <seller>QSAMP2</seller>
        <otherPartySubmitted>false</otherPartySubmitted>
        <asType>ECRSS</asType>
        <ASSchedule>
            <TmPoint>
                <time>2021-11-02T00:00:00.000-05:00</time>
                <ending>2021-11-02T01:00:00.000-05:00</ending>
                <value1>32</value1>
            </TmPoint>
        </ASSchedule>
    </ASTrade>
    <ASTrade>
        <startTime>2022-01-12T00:00:00-06:00</startTime>
        <endTime>2022-01-12T01:00:00-06:00</endTime>
        <buyer>QSAMP1</buyer>
        <seller>QSAMP2</seller>
        <otherPartySubmitted>false</otherPartySubmitted>
        <asType>ECRSM</asType>
        <ASSchedule>
            <TmPoint>
                <time>2021-11-02T00:00:00.000-05:00</time>
                <ending>2021-11-02T01:00:00.000-05:00</ending>
                <value1>25</value1>
            </TmPoint>
        </ASSchedule>
    </ASTrade>
</BidSet>

And the corresponding response:

<ns1:BidSet xmlns:ns1="http://www.ercot.com/schema/2007-06/nodal/ews">
    <ns1:tradingDate>2022-01-12</ns1:tradingDate>
    <ns1:submitTime>2022-01-10T15:33:03.456-06:00</ns1:submitTime>
    <ns1:ASTrade>
        <ns1:mRID>QSAMP1.20220112.AST.Non-Spin.QSAMP2.QSAMP1</ns1:mRID>
        <ns1:status>SUBMITTED</ns1:status>
    </ns1:ASTrade>
    <ns1:ASTrade>
        <ns1:mRID>QSAMP1.20220112.AST.NSPNM.QSAMP3.QSAMP1</ns1:mRID>
        <ns1:status>SUBMITTED</ns1:status>
    </ns1:ASTrade>
    <ns1:ASTrade>
        <ns1:mRID>QSAMP1.20220112.AST.RRSPF.QSAMP1.QSAMP2</ns1:mRID>
        <ns1:status>SUBMITTED</ns1:status>
    </ns1:ASTrade>
    <ns1:ASTrade>
        <ns1:mRID>QSAMP1.20220112.AST.ECRSS.QSAMP1.QSAMP2</ns1:mRID>
        <ns1:status>SUBMITTED</ns1:status>
    </ns1:ASTrade>
    <ns1:ASTrade>
        <ns1:mRID>QSAMP1.20220112.AST.ECRSM.QSAMP1.QSAMP2</ns1:mRID>
        <ns1:status>SUBMITTED</ns1:status>
    </ns1:ASTrade>
</ns1:BidSet>