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.

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

SPPs Structure

SPP Structure

LMPs Structure

LMP Structure

In both cases the data structure is based upon a PriceSchedule (time, ending, value1 and value2 elements), where values of ‘value1’ and ‘value2’ are in \$/MWh and values of ‘time’ is the absolute start time for the data values. When present, ‘ending’ is the end time for the data values. 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>SP_11</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>SP_12</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>BUS_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>BUS_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>BUS_0003</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>BUS_0004</ns0:bus>
    </ns0:LMP>
</ns0:LMPs>