Domain¶
Exarep operates as a Retail Electric Provider (REP) in the deregulated Texas electricity market. Exarep serves residential and small business customers with simple, fixed-price electricity plans. This document defines the core domain model, business entities, and integration terminology used across all Exarep systems.
Market Structure¶
The Texas deregulated electricity market separates the generation, transmission, distribution, and retail sale of electricity into distinct roles. Exarep participates as a Competitive Retailer (CR), purchasing wholesale electricity and selling it to end-use customers.
Key Market Participants¶
| Participant | Role |
|---|---|
| ERCOT (Electric Reliability Council of Texas) | Independent System Operator (ISO) that manages the Texas power grid, facilitates market transactions, and oversees retail switching |
| Competitive Retailer (CR) | Also called a Retail Electric Provider (REP). Sells electricity to customers and manages their retail accounts |
| Qualified Scheduling Entity (QSE) | Schedules power generation and load with ERCOT on behalf of market participants |
| TDSP (Transmission and Distribution Service Provider) | Owns and operates the physical wires and meters that deliver electricity to premises. Also called a Transmission and Distribution Utility (TDU) |
| Load Serving Entity (LSE) | Entity responsible for serving customer load. A REP acts as the LSE for its customers |
| Provider of Last Resort (POLR) | Designated REP that serves customers when their current REP exits the market or is unable to serve |
TDSPs in the Texas Market¶
| TDSP | DUNS Number | Service Territory |
|---|---|---|
| Oncor Electric Delivery | 007924772 | Dallas-Fort Worth, North and West Texas |
| CenterPoint Energy | 957877905 | Houston metropolitan area |
| AEP Texas | 007929441 | South and West Texas |
| Texas-New Mexico Power (TNMP) | 007929329 | Various areas across Texas |
| Lubbock Power & Light | 195344654 | Lubbock area |
Core Domain Entities¶
ISO¶
An Independent System Operator that manages a power grid and facilitates wholesale electricity market transactions. Exarep operates exclusively within the ERCOT market.
| Field | Description |
|---|---|
| isoId | Unique identifier for the ISO |
| code | Short code for the ISO (e.g. ERCOT) |
| name | Full name of the ISO |
| isoId | code | name |
|---|---|---|
| 1 | ERCOT | Electric Reliability Council of Texas |
TDSP¶
A Transmission and Distribution Service Provider that owns and operates the physical wires and meters delivering electricity to premises. Also called a Transmission and Distribution Utility (TDU).
| Field | Description |
|---|---|
| tdspId | Unique identifier for the TDSP |
| isoId | Reference to the ISO this TDSP operates within |
| code | Short code for the TDSP |
| name | Full name of the TDSP |
| duns | Dun & Bradstreet unique identifier for the TDSP |
| esiidPrefix | 7-digit ESI ID prefix(es) that identify meters in this TDSP's territory |
The first 7 digits of an ESI ID (a 2-digit "10" prefix followed by the 5-digit DOE TDSP identifier) determine which TDSP serves the delivery point. Some TDSPs have multiple prefixes due to mergers or territory divisions.
| tdspId | isoId | code | name | duns | esiIdPrefixes |
|---|---|---|---|---|---|
| 1 | 1 | ONCOR | Oncor Electric Delivery | 007924772 | 1017699, 1044372 |
| 2 | 1 | CNTRPT | CenterPoint Energy | 957877905 | 1008901 |
| 3 | 1 | AEPTXC | AEP Texas Central | 007929441 | 1003278 |
| 4 | 1 | AEPTXN | AEP Texas North | 007929441 | 1020404 |
| 5 | 1 | TNMP | Texas-New Mexico Power | 007929329 | 1040051 |
| 6 | 1 | LPL | Lubbock Power & Light | 195344654 | 1011292 |
TdspCharge¶
Date-effective charges set by each TDSP that are passed through to customers. These charges apply to all customers within a TDSP's service territory and can change mid-contract and mid-billing-cycle. When a charge changes during a billing cycle, the bill must prorate the old and new charges based on the number of days each was in effect.
| Field | Description |
|---|---|
| tdspChargeId | Unique identifier for the TDSP charge |
| tdspId | Reference to the TDSP |
| chargeType | TdspFixed, TdspVolumetric |
| amount | Charge amount (monthly dollar amount for TdspFixed; per-kWh rate for TdspVolumetric) |
| effectiveDate | Date this charge becomes effective |
| expirationDate | Date this charge expires |
TDSP Charge Types¶
| Type | Description |
|---|---|
| TdspFixed | Fixed monthly delivery charge assessed regardless of usage (metering, base delivery) |
| TdspVolumetric | Per-kWh delivery charge based on actual usage (transmission, distribution, system benefit) |
TaxJurisdiction¶
A tax jurisdiction representing a municipal, county, state, or special district authority that levies taxes on electricity service. A premise is mapped to a tax jurisdiction based on its location.
| Field | Description |
|---|---|
| taxJurisdictionId | Unique identifier for the tax jurisdiction |
| name | Name of the jurisdiction (e.g. City of Houston, Travis County) |
| jurisdictionType | City, County, State, District |
| state | State |
| county | County (if applicable) |
| city | City (if applicable) |
TaxRate¶
Date-effective tax rates within a jurisdiction. Taxes can change mid-contract and mid-billing-cycle and are applied based on the premise's tax jurisdiction at the time of billing. When a tax rate changes during a billing cycle, the bill must prorate the old and new rates based on the number of days each was in effect.
| Field | Description |
|---|---|
| taxRateId | Unique identifier for the tax rate |
| taxJurisdictionId | Reference to the tax jurisdiction |
| taxType | StateSalesTax, CitySalesTax, FranchiseFee, MiscLocalTax |
| rate | Tax rate as a percentage |
| effectiveDate | Date this tax rate becomes effective |
| expirationDate | Date this tax rate expires |
Customer¶
A customer is either an IndividualCustomer or a BusinessCustomer. Both types share a common set of fields and may have one or more accounts. Exarep serves residential customers and small businesses only. BusinessCustomer's customerId starts with 1000000000001, IndividualCustomer's customerId start at 2000000000001.
IndividualCustomer¶
A residential person who purchases electricity from Exarep.
| Field | Description |
|---|---|
| customerId | Unique identifier for the customer |
| firstName | Customer first name |
| middleName | Customer middle name |
| lastName | Customer last name |
| suffix | Jr., Sr. III, etc |
BusinessCustomer¶
A small business entity that purchases electricity from Exarep.
| Field | Description |
|---|---|
| customerId | Unique identifier for the customer |
| businessName | Legal business name |
| dbaName | Doing-business-as name, if different from legal name |
| ein | Employer Identification Number (federal tax ID) |
| businessType | LLC, Corporation, Partnership, SoleProprietorship, NonProfit |
| preferredLanguage | Communication language preference (English, Spanish) |
Account¶
A billing relationship between Exarep and a customer. An account is associated with one or more premises through AccountPremise, and a single premise may be associated with multiple accounts over time. BusinessCustomer's accountId starts with 1000000000001, IndividualCustomer's accountId start at 2000000000001.
| Field | Description |
|---|---|
| accountId | Unique identifier for the account |
| customerId | Reference to the owning customer |
| accountStatus | Active, Suspended, Closed, PendingEnrollment |
| billingCycle | Day of the month the bill is generated |
| paymentMethod | AutoPay, Manual, BudgetBilling |
| balanceDue | Current outstanding balance |
Premise¶
A physical location where electricity is consumed. A premise has a mailing address and may contain one or more service points. A premise exists independently of any account and may be associated with multiple accounts over time through AccountPremise.
| Field | Description |
|---|---|
| premiseId | Unique identifier for the premise |
| addressLine1 | Street address |
| addressLine2 | Unit, suite, or apartment number |
| city | City |
| state | State (TX) |
| zip | ZIP code |
| county | County name |
| premiseType | SingleFamily, MultiFamily, SmallBusiness |
| taxJurisdictionId | Reference to the tax jurisdiction for this location |
AccountPremise¶
A join entity representing the many-to-many relationship between accounts and premises. Tracks the time period during which an account is associated with a given premise. When a customer moves out, the record is end-dated, and a new record is created when a different customer moves into the same premise.
| Field | Description |
|---|---|
| accountPremiseId | Unique identifier for the association |
| accountId | Reference to the account |
| premiseId | Reference to the premise |
| startDateTime | DateTime the account became associated with the premise |
| endDateTime | DateTime the account association ended (null if currently active) |
Service Point¶
A metered delivery point at a premise where Exarep has an active customer relationship. This entity only contains service points for which Exarep holds a contract — it does not represent the full universe of ESI IDs in the Texas market. The complete ESI ID dataset is maintained separately in ServicePointErcot.
| Field | Description |
|---|---|
| servicePointId | Unique identifier for the service point |
| premiseId | Reference to the premise |
| esiId | ERCOT-assigned Electric Service Identifier (17-digit numeric string) |
| tdspId | Reference to the TDSP that owns the meter and delivery infrastructure |
| meterType | AMS (Advanced Metering System), IDR (Interval Data Recorder), NIDR (Non-IDR) |
| meterReadCycle | TDSP-assigned cycle for scheduled meter reads |
| serviceStatus | Active, Inactive, PendingEnrollment, PendingSwitch, PendingMoveIn, PendingMoveOut |
ServicePointErcot¶
The full ESI ID dataset sourced from ERCOT MIS. This data is scraped from two ERCOT reports:
- ESI ID Service History and Usage Extract — A private, daily extract (Report Type ID 210) delivered to subscribed market participants via the ERCOT MIS. Contains ESI ID relationships, characteristics, and NIDR usage data used in settlement. Also known as the "727 Extract" (from SCR 727).
- TDSP ESI ID Report — A public extract (Report Type ID 203) available on ERCOT.com and the MIS. Contains characteristic and service address information for all registered ESI IDs by TDSP territory. Available as a full monthly extract and daily incremental updates.
This table serves as Exarep's local mirror of the ERCOT registration database for prospecting, enrollment validation, and settlement reconciliation. It is independent of whether Exarep has a customer relationship with the ESI ID.
| Field | Description |
|---|---|
| servicePointErcotId | Unique identifier for the record |
| esiId | ERCOT-assigned Electric Service Identifier (17-digit numeric string) |
| address | Registered street address |
| addressOverflow | Address overflow information (unit, suite, etc.) |
| city | Registered city |
| state | Registered state |
| zipCode | Registered ZIP code |
| county | County assigned by the TDSP |
| tdspDuns | DUNS number of the TDSP in whose territory the ESI ID resides |
| tdspName | Name of the TDSP |
| stationCode | TDSP station code identifying the substation serving the ESI ID |
| stationName | Long name of the substation |
| meterReadCycle | TDSP/MRE meter read cycle code |
| status | ESI ID status (Active, Inactive, De-energized) |
| premiseType | Premise classification (Residential, SmallNonResidential, LargeNonResidential) |
| powerRegion | Power region the ESI ID is electrically connected to (ERCOT, SPP, SERC, WSCC) |
| metered | Whether the ESI ID has a physical meter (Y/N, derived from profile type) |
| polrCustomerClass | Calculated POLR customer class (Residential, SmallNonResidential, MediumNonResidential, LargeNonResidential) |
| settlementAmsIndicator | Whether an advanced meter is installed at the premise (Y/N) |
| tdspAmsIndicator | TDSP-provisioned AMS meter type (AMSM, AMSR, or null) |
| switchHoldIndicator | Whether switch holds are present at ERCOT (Y/N) |
| meteredServiceType | Primary type of service being metered |
ESI ID Structure¶
The ESI ID (Electric Service Identifier) is the foundational identifier in the Texas retail market. Every retail transaction references an ESI ID.
| Segment | Digits | Description |
|---|---|---|
| TDSP Code | 1-3 | Identifies the TDSP |
| Station | 4-7 | TDSP station or service area |
| Meter | 8-16 | Unique meter identifier within TDSP |
| Check Digit | 17 | Validation digit |
Plan¶
An electricity plan offered to customers. Exarep offers fixed-price plans at 12, 24, and 36 month terms, plus a month-to-month rollover plan. PUCT rules use the term "product" — Exarep uses plan to refer to the same concept across all systems.
| Field | Description |
|---|---|
| planId | Unique identifier for the plan |
| planName | Marketing name of the plan |
| planType | Fixed, MonthToMonth |
| termMonths | Contract term in months (12, 24, or 36 for Fixed; 0 for MonthToMonth) |
| earlyTermFee | Fee charged for early termination of a fixed-term contract (not applicable for MonthToMonth) |
| active | Whether the plan is currently available for enrollment |
| effectiveDate | Date the plan becomes available |
| expirationDate | Date the plan is no longer available for new enrollments |
Plan Types¶
Per PUCT §25.475, Exarep's plans fall into the following regulatory classifications:
| Type | Term | PUCT Classification | Description |
|---|---|---|---|
| Fixed 12 | 12 months | Fixed Rate Product | A fixed per-kWh energy rate locked in for 12 months |
| Fixed 24 | 24 months | Fixed Rate Product | A fixed per-kWh energy rate locked in for 24 months |
| Fixed 36 | 36 months | Fixed Rate Product | A fixed per-kWh energy rate locked in for 36 months |
| MonthToMonth | Rolling (≤31 days) | Month-to-Month | Rollover plan at $0.20 per kWh with no long-term commitment, no early termination fee |
Fixed Rate Product (PUCT §25.475(b)(5)) — A plan with a term of at least three months for which the price for each billing period is the same throughout the contract term, except the price may vary solely to reflect actual changes in TDU charges, ERCOT administrative fees, or changes resulting from federal, state, or local laws that impose new or modified fees beyond the REP's control.
Month-to-Month Contract (PUCT §25.475(b)(7)) — A contract with a term of 31 days or less. A month-to-month contract may not contain a termination fee or penalty.
When a fixed-term contract expires without renewal, the customer automatically rolls over to the MonthToMonth plan at $0.20 per kWh until they select a new fixed-term plan. This MonthToMonth plan serves as the default renewal plan required by PUCT §25.475(e)(2)(A).
Rate¶
The energy charge for a plan within a TDSP territory. This is the rate that gets locked onto a contract at signing. TDSP delivery charges and taxes are handled separately through TdspCharge and TaxRate.
| Field | Description |
|---|---|
| rateId | Unique identifier for the rate |
| planId | Reference to the associated plan |
| tdspId | Reference to the TDSP this rate applies to (rates vary by TDSP service territory) |
| energyChargeKwh | Per-kWh energy charge (fixed for the contract term; $0.20 for MonthToMonth) |
| effectiveDate | Date the rate becomes effective |
| expirationDate | Date the rate expires |
Contract¶
A binding agreement between Exarep and a customer for electricity service at a specific service point under a specific plan and rate.
| Field | Description |
|---|---|
| contractId | Unique identifier for the contract |
| accountId | Reference to the account |
| servicePointId | Reference to the service point |
| planId | Reference to the plan |
| rateId | Reference to the rate record used at signing |
| lockedEnergyChargeKwh | Per-kWh energy charge frozen at contract signing, copied from the Rate at signing time |
| contractStatus | Active, PendingStart, Expired, Terminated, Renewed, RolledOver |
| startDate | Contract effective start date |
| endDate | Contract scheduled end date (null for MonthToMonth) |
| signedDate | Date the customer signed the contract |
| termsOfServiceUrl | URL to the terms of service / EFL (Electricity Facts Label) |
| yracUrl | URL to the Your Rights as a Customer document |
Contract Lifecycle¶
Fixed-Term Contract:
PendingStart → Active → Expired → RolledOver (to MonthToMonth)
→ Terminated (early termination, incurs fee)
→ Renewed (customer selects a new fixed-term plan)
MonthToMonth Contract:
Active → Terminated (customer cancels or switches to a fixed-term plan)
When a fixed-term contract reaches its end date without renewal, the system automatically creates a new MonthToMonth contract at $0.20 per kWh. If the REP fails to provide required expiration notices, the REP must continue serving the customer under the original fixed-rate terms until proper notice is given (PUCT §25.475(e)(1)(C)).
Contract Expiration Notices (PUCT §25.475(e))¶
For fixed-rate contracts, the REP must provide at least three written notices of the contract expiration date. Notices must be distributed during the last third of the contract period at roughly even intervals.
| Contract Term | First Notice May Begin | Final Notice Deadline |
|---|---|---|
| 12 months | Up to 3 months before | At least 30 days before expiry |
| 24 months | Up to 3 months before | At least 30 days before expiry |
| 36 months | Up to 3 months before | At least 30 days before expiry |
The final notice must include the EFL for the default renewal plan (MonthToMonth) and a statement that the customer will automatically be enrolled in the default renewal plan if no action is taken. The default renewal plan must be a month-to-month plan that the customer may cancel at any time without a fee.
Contract Documents (PUCT §25.475(b)(1))¶
Per PUCT rules, a contract consists of the following documents, all of which must be provided to the customer at enrollment:
| Document | Abbreviation | Description |
|---|---|---|
| Terms of Service | TOS | Full contractual terms and conditions, including fees, deposit policy, rescission instructions |
| Electricity Facts Label | EFL | Standardized pricing disclosure showing average price at 500, 1,000, and 2,000 kWh (residential) or 1,500, 2,500, and 3,500 kWh (small commercial) |
| Your Rights as a Customer | YRAC | Summary of customer protections including complaint resolution, payment assistance, outage reporting, disconnection protections, and critical care/chronic condition designations |
Each document must be assigned a version number, written in plain language with font no smaller than 10 point, and retained by the REP for four years after the contract ceases to be in effect. Documents must be provided to the customer upon any change and upon request at no charge.
Enrollment¶
The process of establishing or transferring electricity service for a customer at a service point. Enrollments trigger ERCOT market transactions and must comply with PUCT §25.474 enrollment requirements.
| Field | Description |
|---|---|
| enrollmentId | Unique identifier for the enrollment |
| contractId | Reference to the associated contract |
| servicePointId | Reference to the service point (ESI ID) |
| enrollmentType | Switch, MoveIn, MoveOut, Rescission |
| enrollmentStatus | Pending, Submitted, Accepted, Rejected, Completed, Cancelled, Rescinded |
| enrollmentChannel | Internet, Written, DoorToDoor, Telephonic |
| requestedDate | Requested effective date of service |
| effectiveDate | Actual effective date confirmed by ERCOT/TDSP |
| submittedDate | Date the enrollment transaction was submitted to ERCOT |
| completedDate | Date the enrollment was fully processed |
| rejectionCode | ERCOT/TDSP rejection reason code if rejected |
| rejectionReason | Human-readable rejection reason |
| rescissionDeadline | Deadline for rescission rights (3 federal business days after TOS receipt, switches only) |
Enrollment Types¶
| Type | Description |
|---|---|
| Switch | Customer transfers service from another REP to Exarep at an existing service point |
| MoveIn | Customer initiates new service at a premise, either at an active or inactive service point |
| MoveOut | Customer discontinues service at a premise, triggering a drop transaction |
| Rescission | Customer cancels a switch enrollment within the rescission period |
Right of Rescission (PUCT §25.474(j))¶
For switch requests only, the customer has the right to rescind the terms of service without penalty or fee of any kind for a period of three federal business days after receiving the TOS document. The right of rescission does not apply to move-in requests. The REP may submit the switch request to ERCOT before the rescission period expires, but must cancel the switch and return the customer to their chosen REP at no cost if the customer exercises the rescission right.
Enrollment Authorization Requirements (PUCT §25.474)¶
Regardless of enrollment channel, the REP must disclose and verify the following before submitting a switch or move-in:
- Name of the REP and the specific plan
- Price of the plan stated in cents per kWh
- Contract term length
- Presence or absence of early termination fees and applicable amounts
- Any deposit requirements and estimated amount
- Right of rescission (for switches)
- Account access verification data (last 4 of SSN, mother's maiden name, city of birth, DOB, or driver's license number)
Authorization and verification records must be retained for 24 months from the date of initial enrollment.
Bill¶
An invoice generated for a customer account covering a specific billing period. Includes energy charges, TDSP pass-through charges, taxes, and fees. Billing must comply with PUCT §25.479 requirements.
| Field | Description |
|---|---|
| billId | Unique identifier for the bill |
| accountId | Reference to the account |
| billNumber | Human-readable bill number |
| billingPeriodStart | Start date of the billing period |
| billingPeriodEnd | End date of the billing period |
| statementDate | Date the bill was generated |
| dueDate | Payment due date (at least 16 days after statementDate per PUCT §25.480) |
| totalAmountDue | Total amount owed |
| averagePriceKwh | Average price per kWh for the billing period displayed in cents per kWh to the nearest 0.1 cent |
| previousBalance | Balance carried forward from prior billing period |
| paymentsReceived | Payments received since last bill |
| adjustments | Credits or debits applied |
| latePenalty | One-time delinquency penalty, not exceeding 5.0% of the delinquent amount (PUCT §25.480) |
| billStatus | Generated, Sent, Paid, PastDue, Disputed, WrittenOff |
Billing Requirements (PUCT §25.479)¶
- Bills must be issued monthly and no later than 30 days after the REP receives usage data from the TDSP
- Residential bills must be delivered by U.S. mail; electronic delivery only with customer consent
- Bills must include: REP certification number, toll-free complaint number, 24/7 outage reporting number, ESI ID, meter reads, service period, average price per kWh, and itemized non-recurring fees
- The fixed-rate contract expiration date must appear in bold and underlined type
- Page 1 of residential bills must include "for more information about residential electric service please visit www.powertochoose.com" in 12-point font or larger
- Billing and payment records must be retained for 24 months
Bill Line Items¶
Each bill contains line items that break down the charges. Energy charges are calculated from the contract's locked rate, TDSP charges from the active TdspCharge records for the service point's TDSP, and taxes from the active TaxRate records for the premise's tax jurisdiction. Because TDSP charges and tax rates can change mid-billing-cycle, each line item covers a specific sub-period of the billing cycle via periodStart and periodEnd. When a rate change occurs mid-cycle, multiple line items of the same charge type are generated — one for each effective rate period.
| Field | Description |
|---|---|
| billLineItemId | Unique identifier for the line item |
| billId | Reference to the parent bill |
| servicePointId | Reference to the service point this charge applies to |
| chargeType | Energy, TdspFixed, TdspVolumetric, Tax, Fee, Credit, LateFee |
| description | Human-readable charge description |
| periodStart | Start date of the sub-period this line item covers (inclusive) |
| periodEnd | End date of the sub-period this line item covers (inclusive) |
| daysInPeriod | Number of days in this sub-period |
| totalDays | Total number of days in the full billing cycle (used for proration ratio) |
| tdspChargeId | Reference to the specific TdspCharge record applied (for TdspFixed and TdspVolumetric types) |
| taxRateId | Reference to the specific TaxRate record applied (for Tax type) |
| quantity | Usage quantity in kWh for this sub-period (for usage-based charges) |
| unitPrice | Per-unit price from the applicable rate record |
| amount | Total charge amount for this sub-period |
Billing Calculation¶
| Charge Type | Source | Calculation |
|---|---|---|
| Energy | lockedEnergyChargeKwh from the Contract |
Locked rate x total usage kWh (single line item — energy rate does not change mid-cycle) |
| TdspFixed | Active TdspCharge(s) where chargeType = TdspFixed |
(Monthly amount / totalDays) x daysInPeriod — one line item per effective rate period |
| TdspVolumetric | Active TdspCharge(s) where chargeType = TdspVolumetric |
Per-kWh rate x prorated usage kWh — one line item per effective rate period |
| Tax | Active TaxRate(s) for the premise's TaxJurisdiction | Tax rate x prorated taxable charges — one line item per effective rate period per tax type |
Mid-Cycle Rate Change Example¶
A billing cycle runs June 1–30. The TDSP fixed charge changes from $5.25 to $5.75 on June 16.
Line Item 1: TdspFixed | Jun 1–15 | 15 days / 30 total | $5.25 x (15/30) = $2.625
Line Item 2: TdspFixed | Jun 16–30 | 15 days / 30 total | $5.75 x (15/30) = $2.875
Total TdspFixed charge: $5.50
For volumetric charges, usage is apportioned across sub-periods. With AMS interval data, actual usage per sub-period is available. For NIDR meters, usage is allocated proportionally by number of days in each sub-period.
Payment¶
A payment made by a customer against an account balance.
| Field | Description |
|---|---|
| paymentId | Unique identifier for the payment |
| accountId | Reference to the account |
| paymentAmount | Amount of the payment |
| paymentDate | Date the payment was made |
| paymentMethod | CreditCard, DebitCard, ACH, Check, Cash, MoneyOrder |
| paymentStatus | Pending, Processed, Failed, Refunded, Reversed |
| confirmationCode | Payment processor confirmation code |
| billId | Reference to the bill being paid (optional, payments can apply to balance) |
ERCOT Integration¶
All retail market transactions between REPs, TDSPs, and ERCOT are facilitated through the Texas Standard Electronic Transaction (Texas SET) protocol. Texas SET uses EDI (Electronic Data Interchange) formatted transactions.
Market Identifiers¶
| Identifier | Description |
|---|---|
| DUNS Number | Dun & Bradstreet unique identifier for each market participant (REP, TDSP, QSE) |
| ESI ID | 17-digit Electric Service Identifier assigned to each metered delivery point |
| CR Certificate | PUCT-issued certificate number authorizing a REP to operate in the Texas market |
| Market Participant ID | ERCOT-assigned identifier used in market systems and settlements |
Texas SET Transactions¶
Texas SET transactions are the EDI messages exchanged between market participants. The key transaction types used by a REP are:
814 - Service Enrollment and Switching¶
The 814 transaction handles all service initiation, transfer, and termination requests.
| Transaction Code | Direction | Description |
|---|---|---|
| 814_01 | REP → ERCOT | Enrollment request (switch or move-in) |
| 814_02 | ERCOT → REP | Enrollment acknowledgment or rejection |
| 814_03 | REP → ERCOT | Move-out / drop request |
| 814_04 | ERCOT → REP | Move-out acknowledgment |
| 814_05 | REP → ERCOT | Rescission of a pending enrollment |
| 814_06 | ERCOT → REP | Rescission acknowledgment |
| 814_20 | ERCOT → REP | Notification of customer gain (another REP's customer switching to you) |
| 814_21 | ERCOT → REP | Notification of customer loss (your customer switching away) |
| 814_24 | ERCOT → REP | Enrollment completion notification with effective date |
| 814_25 | REP → ERCOT | Change request (name change, rate class change) |
867 - Usage Data¶
The 867 transaction delivers metered usage data from TDSPs to REPs, used for billing and settlement.
| Transaction Code | Direction | Description |
|---|---|---|
| 867_01 | TDSP → REP | Monthly usage (NIDR customers, single register read) |
| 867_03 | TDSP → REP | Interval usage data (IDR and AMS meters, 15-minute intervals) |
| 867_04 | TDSP → REP | Historical usage (provided during enrollment for new customers) |
| 867_05 | TDSP → REP | Final meter read at move-out |
810 - TDSP Billing¶
The 810 transaction delivers TDSP charges to the REP for pass-through billing to customers.
| Transaction Code | Direction | Description |
|---|---|---|
| 810_01 | TDSP → REP | TDSP invoice with delivery and transmission charges |
| 810_02 | TDSP → REP | TDSP invoice adjustment or correction |
820 - Payment¶
The 820 transaction handles payment remittance between REPs and TDSPs.
| Transaction Code | Direction | Description |
|---|---|---|
| 820_01 | REP → TDSP | Payment remittance for TDSP charges |
248 - Usage Reporting to ERCOT¶
| Transaction Code | Direction | Description |
|---|---|---|
| 248_01 | TDSP → ERCOT | Aggregated usage data for settlement purposes |
ERCOT Systems¶
| System | Description |
|---|---|
| MarkeTrak | ERCOT's case management system for resolving retail market transaction disputes |
| NAESB EIP | Electronic Interface Protocol for submitting and receiving Texas SET transactions |
| ERCOT MIS | Market Information System for settlement data, reports, and market notices |
| Texas SET Hub | Central clearinghouse for routing EDI transactions between market participants |
| NMMS | Nodal Metering Management System for meter registration and data management |
Enrollment Lifecycle¶
The typical enrollment lifecycle for a switch transaction:
1. Customer selects plan and signs contract
2. REP submits 814_01 enrollment request to ERCOT
3. ERCOT validates the request (ESI ID, TDSP, eligibility)
4. ERCOT sends 814_02 acknowledgment (accepted or rejected)
5. If accepted, ERCOT sends 814_20 gain notification to gaining REP
6. ERCOT sends 814_21 loss notification to losing REP
7. TDSP processes the meter switch on the effective date
8. ERCOT sends 814_24 completion notification with effective date
9. Customer is now served by Exarep
Switch Hold¶
A switch hold prevents an ESI ID from being switched to a new REP. Switch holds are placed by the current REP through ERCOT's systems. Per PUCT §25.480(l-m), switch holds may be used for:
- Deferred payment plans (DPP)
- Delinquent level or average payment plans
The customer must receive oral and written explanation before placement. Switch holds must be released before a competing REP can complete a switch enrollment. If the customer's fixed-rate contract expires while a switch-hold is active, the REP must move the customer to its lowest-priced month-to-month plan with no early termination fees.
TDSP Integration¶
Meter Types¶
| Type | Full Name | Description |
|---|---|---|
| AMS | Advanced Metering System | Smart meter with 15-minute interval recording and remote read capability. Standard for residential in most TDSP territories |
| IDR | Interval Data Recorder | Records usage in 15-minute intervals, typically for small commercial customers with higher demand |
| NIDR | Non-Interval Data Recorder | Traditional meter with monthly cumulative reads, legacy meter type |
TDSP Rate Classes¶
TDSPs assign rate classes that determine delivery charge structures. Exarep supports the following rate classes:
| Category | Description |
|---|---|
| Residential | Single-family and multi-family dwellings, secondary voltage |
| Small Commercial | Small business, secondary voltage, demand below threshold |
Load Profiles¶
For NIDR meters without interval data, TDSPs assign load profiles that model expected usage patterns across 15-minute intervals. Load profiles are used by ERCOT for settlement until actual meter reads are available.
| Profile Type | Description |
|---|---|
| RESHIWR | Residential High Winter Ratio |
| RESLOWR | Residential Low Winter Ratio |
| RESMHIWR | Residential Medium High Winter Ratio |
| RESMLWR | Residential Medium Low Winter Ratio |
| BUSLOWTLF | Business Low Transmission Loss Factor |
| BUSMEDLF | Business Medium Load Factor |
Settlement¶
ERCOT settles the wholesale cost of electricity between market participants. Settlement involves:
| Concept | Description |
|---|---|
| Initial Settlement | Preliminary settlement using estimated usage (load profiles) within days of delivery |
| Final Settlement | True-up settlement using actual metered data, typically 55 days after delivery |
| Resettlement | Correction to final settlement based on revised meter data or dispute resolution |
| UFE | Unaccounted For Energy — difference between total generation and total metered consumption |
| Congestion Charges | Charges based on transmission congestion between generation and load zones |
| Ancillary Services | Charges for grid reliability services (regulation, reserves, responsive reserve) |
Regulatory Requirements¶
Exarep operates under the jurisdiction of the Public Utility Commission of Texas (PUCT). The primary rules governing REP operations are found in PUCT Chapter 25, Subchapter R — Customer Protection Rules for Retail Electric Service.
Key PUCT Rules¶
| Rule | Title | Relevance to Exarep |
|---|---|---|
| §25.471 | General Provisions | Definitions and scope of customer protection rules |
| §25.474 | Selection of Retail Electric Provider | Enrollment authorization, verification, and rescission rights |
| §25.475 | General REP Requirements and Disclosures | Plan types, contract terms, EFL/TOS/YRAC, expiration notices |
| §25.477 | Refusal of Electric Service | Acceptable and prohibited grounds for refusing service |
| §25.478 | Credit Requirements and Deposits | Deposit caps, refund timelines, letter of guarantee |
| §25.479 | Issuance and Format of Bills | Billing frequency, content, delivery, and record retention |
| §25.480 | Bill Payment and Adjustments | Due dates, late penalties, overbilling, switch-hold rules |
| §25.481 | Unauthorized Charges | Customer consent, remediation, prohibited billing practices |
| §25.483 | Disconnection of Service | Notice requirements, prohibited periods, reconnection timelines |
| §25.493 | Acquisition and Transfer of Customers | Requirements for transferring customers between REPs |
| §25.495 | Unauthorized Change of REP | Slamming protections and resolution process |
Credit and Deposits (PUCT §25.478)¶
- Total deposits cannot exceed the greater of one-fifth (20%) of estimated annual billing or the sum of estimated billings for the next two months
- Deposits earn interest at the commission-set rate (established by December 1 each year)
- Deposits must be refunded after 12 consecutive residential billing periods without late payment (24 for non-residential)
- REPs cannot require an initial deposit from existing residential customers unless they were late more than once in the prior 12 months or were disconnected for nonpayment
Disconnection Rules (PUCT §25.483)¶
- Only the TDU performs physical disconnect/reconnect; the REP requests it
- Disconnection notice must be a separate mailing, issued no earlier than the day after the bill due date, with a disconnection date at least 10 days after notice issuance
- Prohibited disconnections: during extreme weather (high ≤ 32°F with 24-hour forecast, or NWS heat advisory within prior 2 calendar days), on weekends/holidays, for amounts under dispute, for prior occupant debt, or for estimated bills
- Critical Care customers: up to 63-day disconnection moratorium with physician certification and a deferred payment plan
- Chronic Condition customers: 21-day advance written notice required
- Reconnection timelines: REP must request reconnection from TDU within specific windows based on when payment is received (e.g., payment before 12:00 PM → request by 2:00 PM same day)
Switch-Hold Rules (PUCT §25.480(l-m))¶
- REPs may place switch-holds on accounts with deferred payment plans or delinquent level/average payment plans
- Customer must receive oral and written explanation before a switch-hold is placed
- Once the customer satisfies the obligation by 10:00 PM on a business day, the REP must request removal by noon the next business day
- If a fixed-rate contract expires during a switch-hold, the customer must be moved to the lowest-priced month-to-month plan with no early termination fees
- Erroneous placement or failure to remove on time is a Class B Violation
Overbilling and Underbilling (PUCT §25.480)¶
- Overbilling: must be corrected for the full period; interest owed if not corrected within 3 billing cycles
- Underbilling: customers are not liable for corrected charges unless billed within 180 days of the underbilling (exceptions: meter tampering or TDU meter error)
- If underbilling is $50 or more, the REP must offer a deferred payment plan for the same length of time as the underbilling period
Glossary¶
| Term | Definition |
|---|---|
| AMS | Advanced Metering System. Smart meters with 15-minute interval recording |
| CR | Competitive Retailer. A REP certified to sell electricity in the Texas market |
| DPP | Deferred Payment Plan. Payment arrangement for customers unable to pay in full |
| DUNS | Data Universal Numbering System. Unique identifier for market participants |
| EDI | Electronic Data Interchange. Standard format for Texas SET transactions |
| EFL | Electricity Facts Label. Standardized pricing disclosure document (PUCT §25.475(g)) |
| ERCOT | Electric Reliability Council of Texas. The ISO for the Texas grid |
| ESI ID | Electric Service Identifier. 17-digit identifier for a metered delivery point |
| IDR | Interval Data Recorder. Meter that records 15-minute interval data |
| ISO | Independent System Operator. Manages the electric grid and wholesale market |
| kWh | Kilowatt-hour. Standard unit of electricity consumption |
| LOA | Letter of Authorization. Written enrollment document signed by the customer |
| LSE | Load Serving Entity. Entity responsible for serving customer electrical load |
| MarkeTrak | ERCOT's dispute resolution and case management system |
| NIDR | Non-Interval Data Recorder. Traditional cumulative meter |
| PDS | Prepaid Disclosure Statement. Required document for prepaid service products |
| POLR | Provider of Last Resort. Designated REP for customers whose REP exits the market |
| PUCT | Public Utility Commission of Texas. State regulatory authority |
| PURA | Public Utility Regulatory Act. Texas statute governing electric utilities |
| QSE | Qualified Scheduling Entity. Schedules power with ERCOT |
| REP | Retail Electric Provider. Company that sells electricity to end-use customers |
| Rescission | Cancellation of a switch enrollment within 3 federal business days (PUCT §25.474(j)) |
| TCRF | Transmission Cost Recovery Factor. TDSP charge for transmission costs |
| DCRF | Distribution Cost Recovery Factor. TDSP charge for distribution costs |
| TDSP | Transmission and Distribution Service Provider. Owns the wires and meters |
| TDU | Transmission and Distribution Utility. Alternate term for TDSP |
| Texas SET | Texas Standard Electronic Transaction. EDI protocol for retail market transactions |
| TOS | Terms of Service. Full contractual terms and conditions document (PUCT §25.475(f)) |
| UFE | Unaccounted For Energy. Difference between total supply and total metered demand |
| YRAC | Your Rights as a Customer. PUCT-mandated customer rights document (PUCT §25.475(h)) |