Load Profiling Operating Guides (LPOG)

Presented to ERCOT

Retail Market Subcommittee

January 9, 2002

Profiling Working Group

Darryl Nelson, Chair

Load Profiling Operating Guides(LPOG)

Sections of LPOG Approved by RMS:

• Change Control Process for LPOG (3)

• Validation of Load Profile IDs (10)

• Requests for Changes to Profile Segment Definitions (11)

• Requests for Changes to Weather Zone Definitions (12)

• Load Profile Dispute Resolution Process (13)

Summary of Approved Sections

Approval of Approach for 6 sections:

• Purpose of Load Profiling (1)

• Guidelines for Load Profile Development (4)

• Request for Changes to Load Profile Methodology (6)

• Request for Changes to Load Profile Models (7)

• kVa to kW Conversion (9)

• Access to Load Profiling Materials (17)

Goal for Today

Brief Overview

• Part of Settlements

• 15-minute intervals

• Non-IDR customers

• Created in fair and equitable manner

Purpose of Load Profiling

Approval of Approach for 6 sections:

• Purpose of Load Profiling (1)

• Guidelines for Load Profile Development (4)

• Request for Changes to Load Profile Methodology (6)

• Request for Changes to Load Profile Models (7)

• kVa to kW Conversion (9)

• Access to Load Profiling Materials (17)

Goal for Today

Background

• More detail for principles listed in Protocols 18.2.1

• Part of Load Profiling Methodology document, v1.04

• Approved by PWG in May 2000

Guidelines for Load Profile Development

Guidelines

• Minimize total number of load profiles by leveragingexisting load research data

• Incorporate generation cost data into analysis todetermine appropriate number of load profiles

• Suggested issues to be addressed when assigning loadprofiles to areas that do not currently have loadresearch data

(cont’d)

Guidelines for Load Profile Development

Guidelines (cont’d)

• Use readily identifiable parameters to assign loadprofiles

• Use most accurate load research data available

• Possible methods to accommodate Time-of-Use,controlled loads and other similar demand-sidemanagement programs.

(cont’d)

Guidelines for Load Profile Development

Guidelines (cont’d)

• Load profile information shall be consistent, clear,easy to understand, and readily available.

• Load profile methodology shall be fully andunambiguously defined.

Guidelines for Load Profile Development

Approval of Approach for 6 sections:

• Purpose of Load Profiling (1)

• Guidelines for Load Profile Development (4)

• Request for Changes to Load Profile Methodology (6)

• Request for Changes to Load Profile Models (7)

• kVa to kW Conversion (9)

• Access to Load Profiling Materials (17)

Goal for Today

Introduction

ERCOT Board approval is necessary for any changefrom one load profile methodology to another.(Protocols 18.2.9)

This section does not address changes to profilesegments or weather zones.

A request for a load profile methodology change willnot be accepted until 2 years after market open.

Changes to Load Profile Methodology

Current Methodologies

• Adjusted Static - Residential and Commercial

• Engineering Estimates - street lighting and otherconstant loads

• Proxy Day - estimating IDR loads

• Lagged Dynamic Sampling - Direct Load Control

Changes to Load Profile Methodology

Who May Submit

Any market participant, Profiling WG, or ERCOTmay submit a request to change a load profilingmethodology.

Changes to Load Profile Methodology

Timing

• No requests accepted for 2 years

• Submitter of a request will be notified within 2business days by ERCOT of receipt of request andinform submitter of next PWG meeting dates.

• Submitter will present request at next PWGmeeting.

Changes to Load Profile Methodology

Timing (cont’d)

• After request has been presented, ERCOT willrespond within 60 days to address these issues:

- Completeness of request

- Additional data, if needed

- Assessment criteria

- Estimate of time to evaluate request

- Estimate of time to implement request

• A methodology change will only be implementedwith Board approval and at least 12 months notice tomarket participants.

Changes to Load Profile Methodology

Information Required with Request

• State why a change is necessary, why the proposedmethodology is superior to current, and how thebenefits of change outweigh costs to implement.

• Supporting data, such as:

- Analysis of data available in ERCOT systems

- Analysis of load research data not available to ERCOT

- Other data or supporting evidence

Changes to Load Profile Methodology

Evaluation of Request

ERCOT will evaluate the request for change tomethodology using these factors:

• Quality of supporting data

• Magnitude of differences

• Size of affected load profile population

• Effect on rest of market if change is accepted

Changes to Load Profile Methodology

Approval of Request

Ultimate approval by ERCOT Board after followingproper approval sequence through appropriate TACsubcommittees and TAC.

Changes to Load Profile Methodology

Costs for Methodology Changes

The submitter of request will pay all costs associatedwith developing supporting data and documentation.Also, ERCOT may charge a processing fee forevaluating the request.

Costs for implementing changes to ERCOT systemswill be borne by ERCOT.

Changes to Load Profile Methodology

Procedure for Submitting a Request

• Submit request to ERCOT

(All materials in electronic format only)

• Present request to PWG

• PWG, ERCOT, and submitter will jointly reviewrequest

• PWG and ERCOT will determine any additionalsupporting data needed from submitter to evaluaterequest.

Changes to Load Profile Methodology

Approval of Approach for 6 sections:

• Purpose of Load Profiling (1)

• Guidelines for Load Profile Development (4)

• Request for Changes to Load Profile Methodology (6)

• Request for Changes to Load Profile Models (7)

• kVa to kW Conversion (9)

• Access to Load Profiling Materials (17)

Goal for Today

Types of Evaluations

• Routine

ERCOT will perform annual evaluations

• Interim

Request for model performance evaluation frommarket participant, TAC subcommittee, orERCOT.

Profile Models

Implementation of Model Changes

Any changes based on annual and interim evaluationswill be implemented together as part of the annualimplementation of changes (including changes toprofile segments and/or weather zones), unlessevaluation determines a need for a more immediatechange.

Profile Models

Types of Profile Models

Adjusted Static Model

• Most profile segments are adjusted static

• Regression

• Based on load research, weather, and calendar

Engineering Estimates

• Non-metered: lighting and flat

• Assume same operating schedule and same load

• Sunrise/sunset effect on lighting

Profile Models

Evaluations of Adjusted Static

With Current Load Research Data

• Best data for comparison/evaluation

• Factors for Comparison

Load-weighted average price

On/Off Peak ratio

Load factor

Summary statistics on difference in series

Deadweight loss

Without Current Load Research Data

• Old load research data

• Monthly consumption data

Profile Models

Evaluation of Engineering Estimates

• Evaluate any new operating schedules

• Evaluate any new load information

• Compare monthly consumption data

Profile Models

Routine Evaluations

• Compare existing profile model with profile basedon load research data

• Consider any end-use saturation data

• Consider any current data useful for engineeringmodels

• Review magnitude of load migration

• Compare aggregate monthly consumption data withprofile model

• Evaluate weather zone definitions for adequacy ofweather stations and weighting

Profile Models

Interim Evaluations

Same as Routine Evaluation except attention will belimited to those profile segment models and weatherzones that are of concern.

Profile Models

Assessing the Type of Change Needed

Profile Models

Possible Recommendations

• Adjust coefficients for one or more profile segments

• Re-estimate models

• Begin to collect new load research data

• Implement changes to weather zone(s)

• Implement changes to profile segment(s)

• No change

Assessing the Type of Change Needed

Qualitative Criteria

•Determine if serious bias is present

•Determine degree of bias, e.g. modest, extensive

•Implement necessary actions to rectify bias problem:

Adjustment factors

Change definition of weather zone(s)

Limited load research program

Adjust coefficients

Re-estimate models

Profile Models

Criteria for Requiring a Change

• No criteria at this time.

• Criteria might be established after the first annualevaluation is complete.

Profile Models

Procedures for Making a Change

• Approval by the appropriate TAC subcommittee

• Implement changes to Adjusted Static:

Adjustment factors

Model Re-estimation

• New engineering estimates

• Changes will occur annually unless requiredimmediately

Profile Models

Requesting a Change to Models

Procedures

• General info

• Model adjustment factors

• Analysis of data in ERCOT systems

• Analysis of load research data not available toERCOT

• Analysis of other supporting data

• Engineering estimates

• Re-estimation of Models

Profile Models

Approval of Approach for 6 sections:

• Purpose of Load Profiling (1)

• Guidelines for Load Profile Development (4)

• Request for Changes to Load Profile Methodology (6)

• Request for Changes to Load Profile Models (7)

• kVa to kW Conversion (9)

• Access to Load Profiling Materials (17)

Goal for Today

General Info

ESI Ids with demand meters are assigned a LoadProfile type based on average annual load factor. Tocalculate load factor, a demand in kW is needed.

If kVa is metered instead of kW, then the TDSP mustdetermine the appropriate power factor(s) that shouldbe used for the conversion.

This conversion from kVa to kW is used only forassigning the proper load profile type to each ESI ID.

kVa to kW Conversion

Applicable Market Participants

This section applies to any market participant such as:

• TDSP who currently meters kVa

• TDSP who changes from kW to kVa metering

• NOIE that decides to opt-in

• New competitive metering market participant

kVa to kW Conversion

Procedure

• TDSP will conduct a case study to determineappropriate power factor(s) to be used in conversion.

• TDSP will submit case study to ERCOT

• PWG will meet within 30 days of submittal to review

• If PWG approves, then sent to RMS, TAC andBoard for approval as appropriate.

• TDSP implements approved power factor(s)conversion for load profile ID assignments.

kVa to kW Conversion

Power Factor Performance Review

TDSP must periodically review the performance ofthe power factor(s) at the discretion of ERCOT or thePWG.

kVa to kW Conversion

Other Issues

ERCOT and the PWG will specify minimal reportingstandards for power factor analysis to each requestoron a case-by-case basis.

Without approval of the case study, a default powerfactor of 1.0 shall be imposed.

kVa to kW Conversion

Approval of Approach for 6 sections:

• Purpose of Load Profiling (1)

• Guidelines for Load Profile Development (4)

• Request for Changes to Load Profile Methodology (6)

• Request for Changes to Load Profile Models (7)

• kVa to kW Conversion (9)

• Access to Load Profiling Materials (17)

Goal for Today

Daily Load Profiling Market Info

Access to Load Profiling Materials

• Backcasted (Actual) Load Profiles

• Forecasted Load Profiles

Load Profiling Documents

Access to Load Profiling Materials

• Profile File Format

• Profile Decision Tree

• Profile Model Spreadsheets

• Final Profile Model Report

• Load Profile History

• Historical Weather Data by Weather Zone

• Profile Types and Weather Zones

• Profile Data Evaluation Report

Other Materials

Access to Load Profiling Materials

Calendar of Events

Provides information on the PWG meetings

Profiling Working Group Meeting Info

Will contain information similar to Calendar of Events,

but in a more accessible form. Incomplete (gray boxed)