Phase 1 shadow · synthetic · independent  ·  SAWEM Phase 1 Trading Simulator — explainer-grade, not an MMS.  ·  Trading Rules Round 2 (12 April 2026 v01 draft)
Trading day 2026-05-29 virtual hour 00 Auction state: ACCEPTING gate close in 18h:00m DAM clear IDM re-clear Balancing Settlement
SAWEM
Day-ahead clearing

Hour 19 · 2026-05-29

Illustrative clearing — production MMS would use a SCED-class optimiser.

Why this price?

In hour 19, the SMP cleared at R2219.54 / MWh. The marginal offer was Eskom Holdings — OCGT peaker (Generator)'s — the last unit of generation needed to meet demand. By uniform-price rule, every accepted seller was paid R2219.54 / MWh for their share of the 31994 MWh cleared this hour.

See the in-browser verifier to confirm the SMP from the receipt's canonical inputs.

SMP
R2219.54 / MWh
Total dispatch
31,994 MWh
Marginal party
Eskom Holdings — OCGT peaker (Generator)
gen_eskom_ocgt_01

Supply curve · demand intersection

Aggregator — renewables pool — R420/MWh up to 300 MWhIPP — wind plant (Generator) — R431/MWh up to 1394 MWhEskom Holdings — coal fleet (Generator) — R843/MWh up to 31394 MWhCross-border — ZESA interconnect — R1103/MWh up to 31594 MWhEskom Holdings — OCGT peaker (Generator) — R2220/MWh up to 31994 MWhDemand 36000 MWhSMP R2220/MWh

The supply curve (terracotta) is cumulative MWh on the x-axis, offer price on the y-axis. The dashed green line is hourly demand. Where they cross is the SMP.

Accepted awards

Offer Party MWh awarded Price (R/MWh)
o-19-renew-agg Aggregator — renewables pool 300.0 R2219.54
o-19-wind IPP — wind plant (Generator) 1094.0 R2219.54
o-19-coal Eskom Holdings — coal fleet (Generator) 30000.0 R2219.54
o-19-zesa Cross-border — ZESA interconnect 200.0 R2219.54
o-19-ocgt Eskom Holdings — OCGT peaker (Generator) 400.0 R2219.54
Show full computation transcript
[clearHour] day=2026-05-29 hour=19 seed=42
[clearHour] tieBreak=price_asc → ts_asc → party_id_asc
[clearHour] demand_mw_min=2160000
[clearHour] accept offer=o-19-renew-agg party=agg_renewables_01 price=41974c volume=18000 cumulative=18000
[clearHour] accept offer=o-19-wind party=gen_ipp_wind_01 price=43116c volume=65640 cumulative=83640
[clearHour] accept offer=o-19-coal party=gen_eskom_coal_01 price=84346c volume=1800000 cumulative=1883640
[clearHour] accept offer=o-19-zesa party=cb_zesa_synthetic price=110289c volume=12000 cumulative=1895640
[clearHour] accept offer=o-19-ocgt party=gen_eskom_ocgt_01 price=221954c volume=24000 cumulative=1919640
[clearHour] SMP=221954c marginal=gen_eskom_ocgt_01

Verify from your laptop (terminal): curl -s /api/clearing/19/replay > receipt.json && npm run verify -- receipt.json

Or in your browser (no install): /clearing/19/verify

Download replay bundle (.json)

Audit chain · stage 1 of 4

Commit this DAM clear to the append-only SHA-256 chain (dam_cleared event). Best-effort: with no D1 binding bound locally this degrades to a "not recorded" marker rather than failing.

Data as-of: 2026-05-29 · Trading Rules R2 v01 (2026-04-12 draft) · Market Code v2.1 · simulator build 2026-05-29.