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
Shadow-day · stage 3 of 4 · balancing & imbalance

Balancing · hour 13 · 2026-05-29

Stage status timestamp (balancing complete): 2026-05-29T14:50:00Z

Illustrative imbalance pricing (Trading Rules R2 §07 placeholder formula). Balancing consumes the final post-IDM schedule and prices each party's deviation from it against the metered outturn.

Reference SMP (IDM)
R864.54 / MWh
Indicative balancing price
R2000.00 / MWh
Net system imbalance
-22.6 MWh
system short (under-delivery)

Per-party imbalance settlement

Metered outturn vs final schedule. A modelled residual under-delivery of 22.6 MWh sits on Eskom Holdings — coal fleet (Generator) so the balancing market has a real action to price.

Party Final sched (MWh) Metered (MWh) Imbalance (MWh) Imb. price (R/MWh) Amount
Eskom Holdings — coal fleet (Generator) 26153.1 26130.5 -22.6 R2000.00 R-45300.00

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).

Audit chain

Commit this balancing run to the append-only SHA-256 chain (balancing_complete event).

Full IDM + balancing transcript
[reclearIntraday] day=2026-05-29 hour=13 seed=42
[reclearIntraday] slip party=agg_renewables_01 -19.7% dam=180000 revised=144555 gap+=35445
[reclearIntraday] slip party=gen_ipp_wind_01 -18.0% dam=54840 revised=44977 gap+=9863
[reclearIntraday] residual_gap=45308 backfilled=45308 uncovered=0 idm_smp=86454c backfill_awards=1
— BALANCING —
[computeBalancing] day=2026-05-29 hour=13
[computeBalancing] party=gen_eskom_coal_01 sched=1569188 metered=1567829 imb=-1359 price=200000c amount=-4530000c
[computeBalancing] net_system_imbalance=-1359 balancing_price=200000c
Shadow-day stage 3/4 · Trading Rules R2 §07 (imbalance) · simulator build 2026-05-29.