Market LMPs, SPPs, Price Corrected LMPs and Price Corrected SPPs

The purpose of this interface is to provide a query for market LMPs, LMPsPC (price corrected LMPs), SPPs and SPPsPC (price corrected SPPs). The request message would use the following message fields:

Message Element	Value
Header/Verb	get
Header/Noun	LMPs (or LMPsPC, SPPs, SPPsPC)
Header/Source	Market participant ID
Header/UserID	ID of user
Request/OperatingDate	Day of the Report For DAM MarketType
Request/StartTime	Start time of interest For RTM MarketType
Request/EndTime	End time of interest For RTM MarketType
Request/MarketType	DAM or RTM

The corresponding response messages would use the following message fields:

Message Element	Value
Header/Verb	reply
Header/Noun	LMPs (or LMPsPC, SPPs, SPPsPC)
Header/Source	ERCOT
Reply/ReplyCode	Reply code, success=OK, error=ERROR or FATAL
Reply/Error	Error message, if error encountered
Payload/	LMPs (or SPPs)

Please note that requesting LMPs and LMPsPC for DAM market is not supported at this time due to its large response payload size. LMPs and LMPsPC values for DAM market can be retrieved via CDR reports or “get Reports” interface specified in section 9.0.

For RTM Market type, the last SCED run time is returned in the TmPoint/time element. The structure of a LMPs/LMPsPC/SPPs/SPPsPC payload is shown by the following diagram, where each LMP/SPP uses a TmSchedule type for each bus or SettlementPoint:

SPPs Structure

SPP Structure

LMPs Structure

LMP Structure

In both cases the data structure is based upon a TmSchedule, where values of ‘value1’ and ‘value2’ are in \$/MWh and values of ‘time’ is the absolute start time for the data values. The last point on the schedule is valid until the endTime. For LMPsPC and SPPsPC responses, ‘value1’ represents the original price and ‘value2’ represents the corrected price. The ‘value2’ element will only be populated for LMPsPC and SPPsPC responses and is not applicable to LMPs and SPPs responses.

For SPPs and SPPsPC the Settlement Point Type (spType) is an optional field and it is not applicable to DAM market but it is populated for the RTM market. It’s possible values are: RES, LZ, HUB.

The following is an XML example for SPPs:

<ns0:SPPs xmlns:ns0="http://www.ercot.com/schema/2007-06/nodal/ews">
    <ns0:SPP>
        <ns0:time>2009-06-20T00:00:00-05:00</ns0:time>
        <ns0:ending>2009-06-20T01:00:00-05:00</ns0:ending>
        <ns0:value1>43</ns0:value1>
        <ns0:sp>PSA_CC1</ns0:sp>
    </ns0:SPP>
    <ns0:SPP>
        <ns0:time>2009-06-20T00:00:00-05:00</ns0:time>
        <ns0:ending>2009-06-20T01:00:00-05:00</ns0:ending>
        <ns0:value1>43</ns0:value1>
        <ns0:sp>FORMOSA_CC1</ns0:sp>
    </ns0:SPP>
    <ns0:SPP>
        <ns0:time>2009-06-20T00:00:00-05:00</ns0:time>
        <ns0:ending>2009-06-20T01:00:00-05:00</ns0:ending>
        <ns0:value1>43</ns0:value1>
        <ns0:sp>LZ_SOUTH</ns0:sp>
    </ns0:SPP>
    <ns0:SPP>
        <ns0:time>2009-06-20T00:00:00-05:00</ns0:time>
        <ns0:ending>2009-06-20T01:00:00-05:00</ns0:ending>
        <ns0:value1>43</ns0:value1>
        <ns0:sp>LZ_WEST</ns0:sp>
    </ns0:SPP>
</ns0:SPPs>

And the following is an XML example for LMPs:

<ns0:LMPs xmlns:ns0="http://www.ercot.com/schema/2007-06/nodal/ews">
    <ns0:LMP>
        <ns0:time>2008-06-19T17:15:22-05:00</ns0:time>
        <ns0:value1>716.1</ns0:value1>
        <ns0:bus>0ABEC_0001</ns0:bus>
    </ns0:LMP>
    <ns0:LMP>
        <ns0:time>2008-06-19T17:15:22-05:00</ns0:time>
        <ns0:value1>716.1</ns0:value1>
        <ns0:bus>0ABEC_0002</ns0:bus>
    </ns0:LMP>
    <ns0:LMP>
        <ns0:time>2008-06-19T17:15:22-05:00</ns0:time>
        <ns0:value1>716.1</ns0:value1>
        <ns0:bus>0AMIST_0001</ns0:bus>
    </ns0:LMP>
    <ns0:LMP>
        <ns0:time>2008-06-19T17:15:22-05:00</ns0:time>
        <ns0:value1>716.1</ns0:value1>
        <ns0:bus>AB_0004</ns0:bus>
    </ns0:LMP>
</ns0:LMPs>