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
Shadow-day · L4 · seller forecast-slip → IDM re-bid

Aggregator — renewables pool — IDM re-bid window

agg_renewables_01

When a variable plant's day-ahead forecast slips beyond −5% at the IDM gate, the seller can re-bid in the intraday market rather than fall straight into the (more expensive) balancing/imbalance settlement.

Hours forecast slipped
21 / 24
Total shortfall (do nothing)
761.3 MWh
Imbalance bill if no re-bid
R1586244.05
priced at the §07 under-delivery premium

Re-bid window · hour 13

IDM gate timestamp: 2026-05-29T14:25:00Z

Day-ahead award 300.0 MWh; forecast slipped -19.7% to 240.9 MWh available — a shortfall of 59.1 MWh. Do nothing and the imbalance bill is R118133.33. There is 316.6 MWh of residual demand to re-bid into at an IDM SMP of R841.83/MWh.

24-hour forecast-slip ledger

Hr DAM award Slip Revised Shortfall Imbalance (do nothing) Re-bid?
00 300.0 -17.9% 246.4 53.6 R107166.67 eligible
01 300.0 1.1% 303.4
02 300.0 -3.3% 290.0 10.0 R20033.33
03 300.0 -19.1% 242.8 57.2 R114466.67 eligible
04 300.0 -16.0% 251.9 48.1 R96266.67 eligible
05 300.0 0.3% 301.0
06 300.0 -2.2% 293.5 6.5 R13033.33
07 300.0 -9.8% 270.6 29.4 R58866.67 eligible
08 300.0 -14.7% 256.0 44.0 R88033.33 eligible
09 300.0 -15.6% 253.1 46.9 R93733.33 eligible
10 300.0 -12.9% 261.3 38.7 R77433.33 eligible
11 300.0 -16.0% 251.9 48.1 R96266.67 eligible
12 300.0 -7.5% 277.6 22.4 R44766.67 eligible
13 300.0 -19.7% 240.9 59.1 R118133.33 eligible
14 300.0 -3.7% 289.0 11.0 R22033.33
15 300.0 -18.0% 246.1 53.9 R107800.00 eligible
16 300.0 -12.8% 261.8 38.3 R76500.00 eligible
17 300.0 -14.2% 257.6 42.5 R106829.67 eligible
18 300.0 -14.5% 256.5 43.5 R109679.41 eligible
19 300.0 -7.1% 278.7 21.3 R54367.61 eligible
20 300.0 -4.7% 286.0 14.0 R35367.36
21 300.0 -13.4% 259.7 40.3 R80600.00 eligible
22 300.0 -10.8% 267.6 32.4 R64866.67 eligible
23 300.0 3.4% 310.2
Shadow-day L4 · forecast-slip → IDM re-bid · Trading Rules R2 §07 · simulator build 2026-05-29.