IEX and PXIL Power Exchange Reconciliation for Indian Open-Access Buyers

A mid-sized auto-component manufacturer in Pune draws 5 MW of open-access power off the IEX day-ahead market for the week ending 31 May 2026. The plant CFO pulls three artefacts at week-end: the exchange trade confirmations (672 cleared blocks of fifteen minutes each), the clearing-bank statement (seven pay-in lines from ICCL), and the SLDC interface meter file (the metered drawal per block, by drawee SDP). Total exchange-cleared cost is ₹2.41 crore for the week at an average clearing price of ₹7.18 per kWh. Total bank debit is ₹2.49 crore. The ₹8 lakh delta — 3.3% — is the reconciliation problem for IEX PXIL power exchange reconciliation India that every open-access buyer recognises by the time they finish their second month of trading.

Quick reference

How does the four-segment architecture work?

The Indian power exchange stack has four segments, each with its own clearing window and settlement shape.

DAM (Day-Ahead Market) is the deepest segment. A double-sided closed auction closes daily at 10:00 hrs on T-1 for delivery in 96 fifteen-minute time blocks on T. Bidders submit price-quantity ladders by block; the exchange runs a market-coupling algorithm to find the market-clearing price per block respecting transmission corridor limits. Cleared trades are physically delivered through the inter-state transmission system. DAM is the workhorse of open-access procurement — most industrial buyers run 60% to 80% of their exchange volume here.

TAM (Term-Ahead Market) offers continuous-trading windows for intra-day, day-ahead contingency, daily and weekly contracts. TAM is used to top-up shortfalls (when DAM bids did not clear at the buyer’s price), to hedge known consumption peaks, and to roll forward weekly contracts when the buyer has a flat baseload requirement.

GTAM (Green Term-Ahead Market) is the renewable-only segment. Sellers must be CERC-registered renewable generators; buyers can elect to use GTAM-cleared volume towards their Renewable Purchase Obligation (RPO). Reconciliation must keep GTAM trades segregated because RPO compliance reporting to the SLDC requires the green attribute to be explicitly tagged on the cleared volume.

RTM (Real-Time Market) clears in half-hour-ahead windows in 48 thirty-minute blocks. RTM is used for last-mile balancing — when the buyer’s actual consumption pattern diverges from the DAM-cleared schedule and the buyer would otherwise be exposed to DSM deviation charges.

What are the four reconciliation rails?

Rail 1 — Trade confirmation versus clearing-bank pay-in

The trade confirmation file from each exchange lists every cleared block: trade ID, segment, delivery date, block number, quantum (in MWh), cleared price, seller and buyer member codes, and the exchange fee. The clearing-bank statement on T+1 shows a single net pay-in or pay-out figure per trading member per exchange. Reconciliation decomposes the bank figure into the constituent trades by summing cleared-value-net-of-fee across all trades for the day, verifying it matches the bank line, and routing exceptions (rare, but they happen when the exchange retries a settlement file after a clearing-corp interface failure).

Rail 2 — Margin block, release and net held

The clearing corporation blocks margin at bid placement. Margin is released on three triggers: order cancellation (block fully reversed), partial fill (proportional release), and trade confirmation (margin converted to settlement value and netted into the T+1 pay-in). Without a margin ledger that mirrors the clearing-corp position, the trading member sees what looks like erratic bank-debit behaviour — funds move daily, sometimes in both directions, for reasons the trade file alone does not explain.

See DISCOM settlement reconciliation for power generators in India for the mirror-image flow on the seller side, where a generator is reconciling exchange pay-out against the discom or third-party-sale invoice.

Rail 3 — Scheduled quantum, metered quantum and DSM deviation

The cleared exchange trade gives rise to a physical schedule submitted to the regional load-dispatch centre (RLDC) and the relevant state load-dispatch centre (SLDC) for both the injection point (seller’s plant) and the drawee point (buyer’s plant). The interface meter at the drawee end records metered quantum per block. The deviation per block — metered minus scheduled — is priced at the frequency-band DSM rate published by the regional pool account and billed monthly.

A buyer who clears 5 MW for a fifteen-minute block (1.25 MWh scheduled) but draws 5.4 MW for that block (1.35 MWh metered) carries a DSM over-drawal of 0.10 MWh, priced at the prevailing frequency-band rate. Reconciliation must price every block’s deviation independently — DSM rates step up sharply at lower frequency bands, so the rupee impact of a small consistent over-drawal during low-frequency hours can be a large percentage of the cleared cost. The DSM monthly bill from the regional pool account is the matching artefact on the bank side; reconciliation ties the internally computed DSM number to the pool-account bill and ages any variance.

Rail 4 — Exchange fee, transmission and GST

Exchange transaction fee — IEX and PXIL each levy a per-MWh transaction fee on cleared volume. The fee is invoiced monthly as a tax invoice carrying GST at 18% under SAC 997159 (financial-and-related services / commodity exchange services). The open-access buyer claims ITC against electricity-input credit if eligible under the state-specific GST treatment of electricity supply.

Transmission charges — CTU/STU/PGCIL transmission charges (open-access charges for inter-state and intra-state wheeling), SLDC scheduling fee, and RLDC operating charges sit on a separate ledger. Transmission of electricity by a transmission utility is generally exempt under the electricity-transmission GST notification. However, certain open-access charges levied by the distribution licensee on consumers (cross-subsidy surcharge, additional surcharge, wheeling charge under the state tariff order) carry their own GST treatment per the state’s notification. The reconciliation has to split the monthly transmission and SLDC bill into the exempt and taxable lines per the relevant state tariff order. See transmission charges reconciliation: CTU/STU/PGCIL billing for the detailed transmission-bill decomposition.

State-tariff true-up — the discom’s annual tariff true-up under the state ERC (MERC, KERC, GERC, etc.) can retroactively adjust cross-subsidy surcharge and additional surcharge applicable to open-access drawal. The true-up creates a back-dated debit or credit that reconciliation must apply to the originating month and not the current month — a frequent source of audit findings. See DISCOM tariff true-up reconciliation under MERC/KERC for the true-up mechanics.

Worked example — Pune auto-component plant, week ending 31 May 2026

A 5 MW open-access drawee runs DAM-led procurement on IEX with TAM top-ups and RTM balancing for the week ending 31 May 2026.

Decomposition of the ₹2.49 crore bank debit against ₹2.41 crore exchange-cleared cost:

• DAM cleared volume: 540 MWh at an average clearing price of ₹7.05 per kWh — gross cleared value ₹38.07 lakh per day, ₹2.27 crore over the seven-day week.
• TAM top-ups: 22 MWh across three intra-day contracts at average ₹7.85 per kWh — ₹1.73 lakh.
• RTM balancing trades (six half-hour blocks across the week): 7 MWh at average ₹8.40 per kWh — ₹0.59 lakh.
• Gross cleared cost (DAM + TAM + RTM): ₹2.29 crore.
• Exchange transaction fee: 569 MWh at the published per-MWh rate — ₹3.41 lakh plus 18% GST of ₹0.61 lakh — total ₹4.02 lakh on the monthly fee invoice, of which the week’s share is ₹0.93 lakh.
• Transmission and SLDC charges (CTU + STU + SLDC scheduling fee per the state tariff order): ₹6.84 lakh for the week, generally GST-exempt.
• DSM net deviation cost (over-drawal in low-frequency blocks net of under-drawal credit in high-frequency blocks): ₹2.21 lakh debit on the regional pool account bill apportioned to the week.
• Cross-subsidy surcharge and additional surcharge (state-tariff-order open-access charges, subject to next true-up): ₹4.42 lakh for the week.

Total landed cost: ₹2.49 crore on a ₹2.29 crore gross cleared base — a 8.7% loading above the exchange-cleared figure. The reconciliation surfaces every component and ties it back to either the clearing-bank statement (exchange settlement and fee), the transmission-utility bill (CTU/STU/SLDC), the regional pool account (DSM), or the discom open-access bill (cross-subsidy and additional surcharge). What looked like an ₹8 lakh unexplained delta at week-open is fully decomposed by week-close.

A 1 MW under-drawal in low-frequency hours one Tuesday afternoon (an unplanned production halt) translated to ₹0.43 lakh of DSM credit — a partial offset that reconciliation flagged for the operations team as a positive variance worth scheduling around. Without block-level reconciliation, that credit gets buried in the monthly net.

What are the operational controls that close the gap?

A trading member who runs a clean exchange reconciliation does six things:

1. Daily trade-confirmation ingest per exchange per segment — the file is published within hours of clearing; ingest it nightly so the next morning’s pay-in tie is automated, not manual.
2. Margin ledger mirrored against the clearing-corp position — block on bid, release on cancel or fill, end-of-day net checked against the clearing-corp statement.
3. Block-level schedule-versus-meter comparison — all 96 DAM blocks reconciled per day, with DSM deviation priced at the published frequency-band rate.
4. Monthly exchange-fee invoice tie — cleared volume from the trade confirmations multiplied by the published per-MWh rate must reconcile to the fee invoice; the 18% GST line must reconcile to the GSTR-2B 2A line for the exchange’s GSTIN.
5. Transmission and SLDC bill decomposition — split into exempt and taxable lines per the state tariff order and routed correctly to GSTR-3B.
6. State ERC true-up reserve — book a provision per kWh of open-access drawal for the expected next true-up of cross-subsidy and additional surcharge, so the eventual back-dated adjustment does not surprise the P&L.

These are operational controls, not technology features. The reconciliation layer makes them auditable. Without the layer, exchange procurement looks like a savings story on the bid side and a leakage story on the settlement side.

How does exchange reconciliation interact with the broader power-utility stack?

A trading-member buyer does not run IEX or PXIL in isolation. The same buyer carries:

• DISCOM bills for the portion of consumption supplied by the local discom (typically the standby line that catches drawal when the open-access schedule falls short) — see DISCOM settlement reconciliation for power generators in India for the consumer-side discom-bill mechanics.
• Transmission utility bills (CTU, STU, PGCIL) for wheeling charges — see transmission charges reconciliation: CTU/STU/PGCIL billing for the inter-state and intra-state wheeling decomposition.
• State-tariff true-up adjustments under MERC, KERC, GERC and equivalent state ERCs — back-dated debits or credits that re-open the originating month’s reconciliation.

The exchange reconciliation is one rail in a four-rail power-utility stack — exchange procurement, discom supply, transmission wheeling, and DSM deviation. A clean rail-by-rail close is what auditors look for in an open-access drawee’s electricity-cost walk-through under CARO 2020 and Ind AS 16 for plant operating expense.

Continue reading in the Power & Utility cluster

• DISCOM settlement reconciliation for power generators in India
• Transmission charges reconciliation: CTU/STU/PGCIL billing
• DISCOM tariff true-up reconciliation under MERC/KERC
• Power & utility reconciliation hub