Shadow-day · stage 2 of 4 · intraday market
IDM re-clear · hour 14 · 2026-05-29
Stage status timestamp (IDM re-cleared): 2026-05-29T15:25:00Z
Illustrative re-clearing — production MMS runs a full intraday SCED. The IDM stage consumes the DAM result for this hour, applies each variable generator's revised forecast, and re-clears the residual gap.
DAM SMP
R849.01 / MWh
IDM SMP
R849.01 / MWh
Residual gap re-cleared
11.0 MWh
from forecast slip on variable plant
Forecast adjustments at the IDM gate
Variable generators (wind / solar / aggregated renewables) revise availability; a slip beyond −5% makes the seller IDM re-bid eligible (the forecast-slip story). Dispatchable plant shows 0% slip.
| Party | DAM award (MWh) | Forecast slip | Revised (MWh) | Gap (MWh) | Re-bid? |
|---|---|---|---|---|---|
| Aggregator — renewables pool | 300.0 | -3.7% | 289.0 | -11.0 | — |
| Eskom Holdings — coal fleet (Generator) | 28243.0 | — | 28243.0 | — | — |
| IPP — solar BW5 (Generator) | 1590.0 | 3.0% | 1637.3 | — | — |
| IPP — wind plant (Generator) | 867.0 | 2.7% | 890.4 | — | — |
IDM backfill awards
Supply re-dispatched to cover the residual gap, paid at the IDM SMP.
| Party | MWh | Price (R/MWh) |
|---|---|---|
| Eskom Holdings — coal fleet (Generator) | 11.0 | R849.01 |
Commit this IDM re-clear to the append-only SHA-256 chain
(idm_re_cleared event). Best-effort: with no D1 binding bound
locally this degrades to a "not recorded" marker rather than failing.
Full DAM + IDM transcript
[clearHour] day=2026-05-29 hour=14 seed=42 [clearHour] tieBreak=price_asc → ts_asc → party_id_asc [clearHour] demand_mw_min=1860000 [clearHour] accept offer=o-14-solar party=gen_ipp_solar_bw5_01 price=36519c volume=95400 cumulative=95400 [clearHour] accept offer=o-14-renew-agg party=agg_renewables_01 price=41890c volume=18000 cumulative=113400 [clearHour] accept offer=o-14-wind party=gen_ipp_wind_01 price=46287c volume=52020 cumulative=165420 [clearHour] accept offer=o-14-coal party=gen_eskom_coal_01 price=84901c volume=1694580 cumulative=1860000 [clearHour] SMP=84901c marginal=gen_eskom_coal_01 — IDM — [reclearIntraday] day=2026-05-29 hour=14 seed=42 [reclearIntraday] slip party=agg_renewables_01 -3.7% dam=18000 revised=17339 gap+=661 [reclearIntraday] residual_gap=661 backfilled=661 uncovered=0 idm_smp=84901c backfill_awards=1