Phase 1 shadow · synthetic · independent  ·  SAWEM Phase 1 Trading Simulator — explainer-grade, not an MMS.  ·  Built from the publicly available Trading Rules; Round 2 not yet gazetted
Trading day 2026-05-29 virtual hour 00 Auction state: ACCEPTING gate close in 18h:00m DAM clear IDM re-clear Balancing Settlement
SAWEM
Generator — my plant

Aggregator — renewables pool

agg_renewables_01

Period: 2026-05-29 (single demo day, 24 hours).

Sign convention — energy revenue: positive (credit). CfD: signed (negative when SMP exceeds strike — seller pays buyer). Imbalance/curtailment: negative when seller under-delivers.

illustrative synthetic outturn The Metered and Dev columns are an illustrative synthetic outturn (solar curtailed 25% in the noon hours, otherwise on schedule), modelled here independently of the IDM / balancing forecast-slip residual shown on the shadow-day stages. The two imbalance models are not yet reconciled. A single-source-of-truth fix is on the roadmap.

Did my offer clear, and why? Open the offer-outcomes panel → (per hour: offer price vs SMP, cleared vs offered, inframarginal/marginal/uncleared)

Forecast slipped? Open the IDM re-bid window → (re-bid intraday instead of falling into balancing — shadow-day stage 2)

Hr SMP Sched Metered illustrative synthetic outturn Dev illustrative Curtail Spot energy CfD Imbalance Net Mirror
00 R847.93 3000.0 3000.0 0.00 0.00 R2 543 790,00 R0,00 R0,00 R2 543 790,00 mirror-confirmed
01 R839.99 3000.0 3000.0 0.00 0.00 R2 519 970,00 R0,00 R0,00 R2 519 970,00 mirror-confirmed
02 R848.83 3000.0 3000.0 0.00 0.00 R2 546 490,00 R0,00 R0,00 R2 546 490,00 mirror-confirmed
03 R851.21 3000.0 3000.0 0.00 0.00 R2 553 630,00 R0,00 R0,00 R2 553 630,00 mirror-confirmed
04 R832.05 3000.0 3000.0 0.00 0.00 R2 496 150,00 R0,00 R0,00 R2 496 150,00 mirror-confirmed
05 R850.31 3000.0 3000.0 0.00 0.00 R2 550 930,00 R0,00 R0,00 R2 550 930,00 mirror-confirmed
06 R833.51 3000.0 3000.0 0.00 0.00 R2 500 530,00 R0,00 R0,00 R2 500 530,00 mirror-confirmed
07 R854.47 3000.0 3000.0 0.00 0.00 R2 563 410,00 R0,00 R0,00 R2 563 410,00 mirror-confirmed
08 R862.87 3000.0 3000.0 0.00 0.00 R2 588 610,00 R0,00 R0,00 R2 588 610,00 mirror-confirmed
09 R842.91 3000.0 3000.0 0.00 0.00 R2 528 730,00 R0,00 R0,00 R2 528 730,00 mirror-confirmed
10 R851.80 3000.0 3000.0 0.00 0.00 R2 555 400,00 R0,00 R0,00 R2 555 400,00 mirror-confirmed
11 R862.87 3000.0 3000.0 0.00 0.00 R2 588 610,00 R0,00 R0,00 R2 588 610,00 mirror-confirmed
12 R856.18 3000.0 3000.0 0.00 0.00 R2 568 540,00 R0,00 R0,00 R2 568 540,00 mirror-confirmed
13 R864.54 3000.0 3000.0 0.00 0.00 R2 593 620,00 R0,00 R0,00 R2 593 620,00 mirror-confirmed
14 R849.56 3000.0 3000.0 0.00 0.00 R2 548 680,00 R0,00 R0,00 R2 548 680,00 mirror-confirmed
15 R838.83 3000.0 3000.0 0.00 0.00 R2 516 490,00 R0,00 R0,00 R2 516 490,00 mirror-confirmed
16 R847.37 3000.0 3000.0 0.00 0.00 R2 542 110,00 R0,00 R0,00 R2 542 110,00 mirror-confirmed
17 R1091.95 3000.0 3000.0 0.00 0.00 R3 275 850,00 R0,00 R0,00 R3 275 850,00 mirror-confirmed
18 R1081.69 3000.0 3000.0 0.00 0.00 R3 245 070,00 R0,00 R0,00 R3 245 070,00 mirror-confirmed
19 R1086.16 3000.0 3000.0 0.00 0.00 R3 258 480,00 R0,00 R0,00 R3 258 480,00 mirror-confirmed
20 R1088.33 3000.0 3000.0 0.00 0.00 R3 264 990,00 R0,00 R0,00 R3 264 990,00 mirror-confirmed
21 R864.37 3000.0 3000.0 0.00 0.00 R2 593 110,00 R0,00 R0,00 R2 593 110,00 mirror-confirmed
22 R869.65 3000.0 3000.0 0.00 0.00 R2 608 950,00 R0,00 R0,00 R2 608 950,00 mirror-confirmed
23 R857.23 3000.0 3000.0 0.00 0.00 R2 571 690,00 R0,00 R0,00 R2 571 690,00 mirror-confirmed
Net to seller · 24-hour demo day R64 123 830,00
Reconciliation Spot energy revenue = SMP × metered MWh. CfD-to-seller = (strike − SMP) × contracted MWh per contract. The matching buyer row for each contract carries the OPPOSITE sign; summing buyer.cfd_diff + seller.cfd_diff for any one contract is zero.
Curtailment & imbalance basis

Implied curtailment haircut: 25% — compensated at 75% of the SMP for involuntarily curtailed energy (the generator forgoes one quarter of spot value). Illustrative, basis pending NERSA (RFD 2025-04-29 — citation unverified).

Implied under-delivery penalty: SMP × 1.15 or an R2 000/MWh floor, whichever is higher. The floor binds when the SMP is below R1 739,13/MWh. Illustrative, basis pending NERSA (Trading Rules R2 §07 placeholder).