Battery‑Assembly Facility
Early 2024, a 68 000 m² lithium‑ion gigafactory in northern Spain was staring at a €3 million cost over‑run. The HVAC contractor insisted on eight additional air‑handling units to maintain ISO‑7 laminar flow in the cell‑forming area. Instead of signing the change‑order, the engineering team built a 48‑hour CFD + discrete‑event digital twin in Siemens Simcenter.
The model mapped heat loads, operator traffic and pressure differentials. It turned out the problem was diffuser orientation, not capacity: rotating 14 ceiling vents by 30°, adding low‑cost directional vanes and rescheduling purge cycles restored 0.35 m/s aisle flow across all shifts. CAPEX dropped from €3 m to €120 k, energy draw fell 21 %, and annual OPEX savings reached €410 k.
Payback shrank from 32 to 20 months, the finance committee approved immediately, and production ramped three weeks ahead of schedule.