Prescription · Full case
Cut Raw Mill 2 idle draw on night windows
Idle cutbackhighInfoneeds review· 2026-07-21
Raw Mill 2 idle draw ran 18% above the night baseline for 47 minutes — auxiliaries and feeders left in warm-idle when no batch was queued.
Potential savings
₹42,000
per month
₹5,04,000 / yr modeled
Root-cause analysis
- Night setback schedule not armed on operator panel.
- Warm-idle floor set too high after last production run.
- No auto-idle timer on feeder auxiliaries.
Recommended action
- Confirm no batch queued in next 60 min, then apply night setback band.
- Log kWh before/after on Mill 2 feeder for savings verification (Option B).
- Escalate if idle returns >10% above baseline within 24 h.
Night idle anomaly
| Metric | Baseline | Observed | Delta |
|---|---|---|---|
| Idle kW | 142 | 168 | +18% |
| Duration | — | 47 min | — |
| Excess kWh (window) | — | 20.3 | — |
What this shows
Elevated idle persists beyond the warm-idle floor when no batch is scheduled. Night setback band would cut ~20 kWh per occurrence.
Sanity check
Confirm no batch queued in next 60 min, apply setback, log kWh for 30 min. Idle should return within 5% of baseline.
Cost–benefit & ROI
≈52,000 kWh/yr from repeated night idle excursions.
| Tariff (₹/kWh) | Annual saving |
|---|---|
| 7.00 | ₹3.6L |
| 8.00 | ₹4.2L |
No CAPEX — validated setback only. Optional auto-timer (~₹40k) for persistent compliance.
Risks & mitigations
| Risk | Mitigation |
|---|---|
| Cold restart delay | Keep warm-idle floor; do not hard-stop auxiliaries. |
KPIs & alerts
| KPI | Target | Alert |
|---|---|---|
| Night idle vs baseline | ≤ +5% | > +10% |
| Idle excursions >30 min | 0 / week | > 2 / week |
Commissioning & verification
- Apply night setback band and log kWh before/after.
- Compare to 14-day baseline for savings verification (Option B).
- Escalate if idle returns >10% above baseline within 24 h.
Ledger entry
Manager takeaway
Night idle on Mill 2 is a zero-CAPEX win — ₹42k/mo recoverable with a validated setback and operator checklist.