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

Balancing · hour 21 · 2026-05-29

Stage status timestamp (balancing complete): 2026-05-29T22:50:00Z

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)

R864.37 / MWh

Indicative balancing price

R2000.00 / MWh

Net system imbalance

-12.1 MWh

system short (under-delivery)

Per-party imbalance settlement

Metered outturn vs final schedule. A modelled residual under-delivery of 12.1 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)	22038.0	22026.0	-12.1	R2000.00	R-24166.67

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=21 seed=42
[reclearIntraday] slip party=agg_renewables_01 -13.4% dam=180000 revised=155817 gap+=24183
[reclearIntraday] residual_gap=24183 backfilled=24183 uncovered=0 idm_smp=86437c backfill_awards=1
— BALANCING —
[computeBalancing] day=2026-05-29 hour=21
[computeBalancing] party=gen_eskom_coal_01 sched=1322283 metered=1321558 imb=-725 price=200000c amount=-2416667c
[computeBalancing] net_system_imbalance=-725 balancing_price=200000c