Phase 5: Billing & Tariff Foundation (The Billing Engine)

Prerequisite Check: Phases 1–4 must be complete. We need: Company Code AEP1 activated for FI-CA (Phase 2, Step 2.1), FI-CA Document Types ZI/ZR (Phase 2, Step 2.3), Account Determination mapped (Phase 2, Step 2.5), Rate Categories assigned to Installation Types (Phase 3), and the complete EDM profile allocation with TOU Period Definitions (Phase 4, Steps 4.7–4.10). This phase builds the billing calculation engine — the operands, rates, and schemas that transform raw interval data into dollar amounts on the customer’s bill.

⚠️ Architecture Constraint — AMI-First Billing: This phase configures billing for a 100% AMI utility. All consumption data enters the billing engine through EDM profile aggregation, not through traditional scalar meter reading differences. The billing schema must reference EDM-sourced TOU operands — standard discrete meter reading logic is forbidden.

Section A: RTP Interface & Formula Profiles (EDM-to-Billing Bridge)

⚠️ Critical Prerequisite: Before defining any operands or rates, you must understand and configure how the raw 15-minute interval data (stored in EDM LOAD/TOU/DEMA profiles from Phase 4) is aggregated into the billing operands. Without this bridge, the billing engine has no consumption values to price against. The billing run (EA00) will abort with error BL 450 (“No consumption data found for operand”).

Step 5.1 — Configure the RTP Interface (EDM → Billing Data Transfer)

SAP Screen Flow

Screen 1 — IMG Navigation

1. Navigate to the SPRO path above → click Execute (⏩).

Screen 2 — EDM Billing Data Transfer: Table View

2. Click New Entries.

Screen 3 — New Entry: Transfer Profile Details

3. Click Save (Ctrl+S).
4. Repeat for each transfer profile:

Complete EDM Transfer Profiles

Data Flow Architecture

EDM Profiles (Phase 4)                    Billing Engine (Phase 5)
─────────────────────                    ────────────────────────
                                          
LOAD Profile ──┐                          
(raw 15-min    │    ┌──────────────┐      ┌─────────────────────┐
 intervals)    ├───→│  RTP / EDM   │─────→│  Billing Operands   │
               │    │  Transfer    │      │                     │
TOU Profile  ──┤    │  Profile     │      │  OP_PEAK  = 450 KWH │
(time-bucketed │    │  (ZEDM_RES)  │      │  OP_OFFP  = 820 KWH │
 consumption)  │    │              │      │  OP_SOFF  = 230 KWH │
               │    │  Aggregation:│      │  OP_DEMA  = 8.5 KW  │
DEMA Profile ──┘    │  Period Sum  │      │  OP_TOTAL = 1500 KWH│
(peak demand)       └──────────────┘      └─────────────────────┘
                                                    │
                                                    ▼
                                          ┌─────────────────────┐
                                          │  Rate Schema        │
                                          │  (price × operand)  │
                                          └─────────────────────┘

Why This Step

In a traditional (non-AMI) utility, billing consumption comes from meter reading differences — the meter reader records a scalar value, and billing subtracts the previous read. For a 100% AMI utility, this entire paradigm is replaced:

1. EDM receives 2,880 fifteen-minute intervals per meter per month (96/day × 30 days)
2. EDM aggregates them using TOU Period Definitions (Phase 4, Step 4.8) into period buckets (PEAK, OFFP, SOFF)
3. The RTP/Transfer Profile pushes these aggregated values into billing operands
4. The billing schema applies prices to those operands

Without the Transfer Profile, there is a data gap between EDM and billing. The TOU profiles contain the data, but billing has no instruction to fetch it.

Step 5.2 — Define Formula Profiles for Billing Calculation

SAP Screen Flow

Screen 1 — IMG Navigation

1. Navigate to the SPRO path above → click Execute (⏩).

Screen 2 — Formula Profiles: Table View

2. Click New Entries.

Screen 3 — New Entry: Formula Profile Header

Screen 4 — Formula Profile: Calculation Steps

3. Click New Entries to define calculation steps within the formula:

4. Click Save (Ctrl+S).
5. Repeat for each formula profile:

Complete Formula Profiles

Why This Step

Formula Profiles are the calculation instruction set that the billing engine executes during EA00. They define:

• What data to fetch from which EDM profile
• How to aggregate that data into operands
• What mathematical operations to apply (summation, peak extraction, netting)

Without a Formula Profile, the billing schema has operand slots but no logic to fill them with values.

Key Configuration Notes

• ⚠️ Standard scalar meter reading formulas (R-S notation) are NOT used in an AMI-first architecture. If you see formula steps referencing “previous read” or “register difference,” you have incorrectly engaged the legacy MR-based billing path.
• The Formula Profile is assigned to the Rate Category in Step 5.5 — not to the installation or contract directly.
• For Net Metering (ZFP_NM), Step 070 calculates OP_NET = OP_TOTAL_DELIVERED - OP_TOTAL_RECEIVED. If OP_NET < 0, the customer has a credit (net excess generation).

Section B: Billing Operands & Rate Types

Step 5.3 — Define Billing Operands

SAP Screen Flow

Screen 1 — IMG Navigation

1. Navigate to the SPRO path above → click Execute (⏩).

Screen 2 — Operands: Table View

SAP displays existing operands (may include SAP-standard entries).

2. Click New Entries.

Screen 3 — New Entry: Operand Details

For each operand, fill in:

3. Click Save (Ctrl+S).
4. Repeat New Entries for each operand:

Complete Billing Operands

Why This Step

Operands are the measurable quantities that the billing engine prices. They represent the “what” in the billing equation (Price × Quantity = Charge). Each operand maps to a specific data source:

• Consumption operands (OP_PEAK, OP_OFFP, etc.) are filled by EDM TOU profile aggregation
• Demand operands (OP_DEMA) are filled by EDM DEMA profile peak extraction
• Fixed operands (OP_CUST) are constants (always = 1 × customer charge rate)
• Calculated operands (OP_TOTAL, OP_NET, OP_PF) are derived from other operands via formula

Key Configuration Notes

• ⚠️ Data Source MUST be EDM for all consumption/demand operands. Setting it to Meter Reading would invoke the legacy scalar-read logic, which is disabled in this AMI-first architecture (MR Relevance = inactive on Installation Type).
• The OP_CRIT (Critical Peak) operand will carry a value of 0 unless a Critical Peak event has been declared via the EDM event overlay mechanism (Phase 4, Step 4.8).
• OP_PF (Power Factor) is calculated as COS(ARCTAN(OP_REACT / OP_TOTAL)) and is used for power factor penalty determination on commercial/industrial accounts.

Step 5.4 — Define Rate Types

SAP Screen Flow

Screen 1 — IMG Navigation

1. Navigate to the SPRO path above → click Execute (⏩).

Screen 2 — Rate Types: Table View

2. Click New Entries.

Screen 3 — New Entry: Rate Type Details

3. Click Save (Ctrl+S).
4. Repeat for each rate type:

Complete Rate Types

Why This Step

Rate Types classify each line item on the customer’s bill. They drive:

• How the charge is calculated (fixed vs. variable vs. calculated)
• Whether sales tax applies
• The print sequence on the customer’s statement
• Regulatory reporting categorization (PUCO requires separate reporting of energy, distribution, and transmission charges)

Section C: Rates & Rate Variants

Step 5.5 — Define Rates (Pricing Rules)

SAP Screen Flow

Screen 1 — IMG Navigation

1. Navigate to the SPRO path above → click Execute (⏩).

Screen 2 — Rates: Table View

2. Click New Entries.

Screen 3 — New Entry: Rate Header

3. Press Enter → navigate to the Rate Lines detail view.

Screen 4 — Rate Lines: Pricing Detail

4. Click New Entries to add pricing lines:

Rate Lines for ZRES-TOU (Residential TOU)

5. Click Save (Ctrl+S).

Calculation Example — Residential TOU

Customer: John Q. Customer
Installation: E2 (Residential TOU)
Billing Period: June 1 – June 30, 2026 (Summer Season)

EDM TOU Profile Output:
  PEAK (3PM–7PM weekdays):  450 KWH
  OFFP (remaining hours):   820 KWH
  SOFF (11PM–5AM):          230 KWH
  CRIT (no event declared):   0 KWH
  TOTAL:                  1,500 KWH

Bill Calculation:
  Line 010: Customer Charge         1 × $8.50   =    $8.50
  Line 020: On-Peak Energy      450 × $0.1200   =   $54.00
  Line 030: Off-Peak Energy     820 × $0.0800   =   $65.60
  Line 040: Super Off-Peak      230 × $0.0500   =   $11.50
  Line 050: Critical Peak         0 × $0.7500   =    $0.00
  Line 060: Fuel Adjustment   1500 × $0.0150   =   $22.50
  Line 070: Transmission      1500 × $0.0085   =   $12.75
  Line 080: Distribution      1500 × $0.0320   =   $48.00
                                                ──────────
  Subtotal (before tax):                          $222.85
  Line 090: State Sales Tax (5.75%):              + $12.81
  Line 091: Municipal Tax (3%):                   +  $6.69
                                                ──────────
  TOTAL AMOUNT DUE:                               $242.35

Step 5.6 — Define Rate Variants (Seasonal / Geographic)

SAP Screen Flow

Screen 1 — IMG Navigation

1. Navigate to the SPRO path above → click Execute (⏩).

Screen 2 — Rate Variants: Table View

2. Click New Entries.

Screen 3 — New Entry: Rate Variant Details

3. Click Save (Ctrl+S).

Complete Rate Variant Definitions

Why This Step

Regulated utilities operate under seasonal rate schedules filed with the state regulator. Summer rates are typically higher due to peak air conditioning load. Rate Variants allow the system to automatically switch pricing based on the billing period dates — the billing engine determines the applicable variant by comparing the billing period start/end dates against the variant validity periods.

Section D: Rate Categories & Billing Schemas

Step 5.7 — Assign Rate Categories

SAP Screen Flow

Screen 1 — IMG Navigation

1. Navigate to the SPRO path above → click Execute (⏩).

Screen 2 — Rate Categories: Table View

Rate Categories were initially defined in Phase 3. This step completes them by assigning the billing components created in this phase.

2. Double-click on each Rate Category to edit:

Screen 3 — Rate Category Details: Billing Assignment Tab

For each Rate Category, assign:

3. Click Save (Ctrl+S).
4. Repeat for every Rate Category:

Complete Rate Category Assignments

Why This Step

The Rate Category is the master switchboard that connects an Installation’s physical metering configuration (EDM Profiles) to the billing engine’s calculation logic (Formula Profile + Rate + Schema). When a billing order runs in EA00, the system looks up the Rate Category on the Contract, which in turn resolves the complete chain of billing components.

Step 5.8 — Define Billing Schemas

SAP Screen Flow

Screen 1 — IMG Navigation

1. Navigate to the SPRO path above → click Execute (⏩).

Screen 2 — Billing Schemas: Table View

2. Click New Entries.

Screen 3 — New Entry: Schema Header

3. Press Enter → navigate to the Schema Lines detail view.

Screen 4 — Schema Lines: Processing Sequence

4. Click New Entries to add processing steps for the billing schema:

Schema Lines for ZSCH_TOU (TOU Billing)

5. Click Save (Ctrl+S).

Complete Billing Schemas

Why This Step

The Billing Schema is the master sequencing engine — it defines the exact order of operations that transforms raw operand values into a finished bill with line items, subtotals, taxes, and a grand total. It is the final piece of the billing puzzle.

Section E: Billing Simulation & Validation

Step 5.9 — Execute Billing Simulation (EA16)

SAP Screen Flow

Screen 1 — Billing Simulation: Selection

1. Execute EA16.
2. Enter selection parameters:

3. Click Execute (⏩).

Screen 2 — Simulation Results

SAP displays the calculated billing output:

Common Simulation Errors

Why This Step

Never go live without simulation. The billing simulation (EA16) runs the complete calculation pipeline without posting any financial documents. It is the only safe way to validate:

• EDM data flows correctly into operands
• Rate pricing applies correctly per TOU period
• Tax calculations are accurate
• The total matches expected values from manual calculation

Step 5.10 — Execute Test Billing Run (EA00)

⚠️ Only execute EA00 after successful EA16 simulation. EA00 creates live FI-CA documents that post to the subledger.

SAP Screen Flow

Screen 1 — Billing: Selection

1. Execute EA00.
2. Enter selection parameters:

3. Click Execute (⏩).

Screen 2 — Billing Results Log

SAP displays processing statistics:

4. Review any errors via Error Log → drill down to individual contract level.
5. Once satisfied, re-run with Test Run = ☐ to execute live posting.

Post-Billing Verification

Why This Step

EA00 is the production billing transaction. In a live system, it runs as a scheduled batch job (typically monthly for residential, daily for commercial/industrial). This step validates the complete end-to-end flow from EDM data through the billing schema to FI-CA document creation.

Phase 5 — Completion Checklist

🔗 The billing engine is now operational. Proceed to Phase 6: Invoicing & Print Formatting to configure how bills are posted to FI-CA and formatted for the customer.