IE4 Upgrade Case Study: 84 Motors, 28% Energy Saving, 14-Month Payback

A textile manufacturing facility in the Bursa industrial zone replaced 84 IE2-class motors across one spinning and weaving production line with IE4 units sourced through INDASTRA. The project, completed over six weeks in Q4 2025, reduced the line's measured electricity consumption by 28% and is projected to deliver full payback in 14 months at current Turkish industrial electricity rates. The facility is now replicating the project across two additional production lines.

Facility and Motor Inventory

The facility produces polyester-cotton blend fabrics for export, operating three production lines 24 hours a day, six days a week (approximately 6,240 annual operating hours per line). The motors being replaced were installed between 2009 and 2014 — predominantly IE1 and IE2 units from several manufacturers including Siemens 1LA7, ABB M2AA, and domestic Turkish brands. Many had accumulated 35,000–50,000 operating hours and were showing increased bearing noise and winding resistance drift indicative of insulation degradation.

The motor inventory on Line 1, targeted for the first phase, consisted of:

• 31 × 2.2 kW, 4-pole, B3 mounting — ring spinning drives
• 22 × 4.0 kW, 4-pole, B5 mounting — draw-frame and roving drives
• 18 × 7.5 kW, 4-pole, B3 mounting — weaving loom main drives
• 13 × 11.0 kW, 4-pole, B5 mounting — warp beam drives and winding machines

Motor Selection and Specification

The replacement specification required IE4 efficiency class, exact IEC frame size matching the existing motors to avoid any modification to motor bases or machine flanges, IE3 minimum for voltage tolerance (400V ±10%, 50 Hz), IP55 protection, and Class F insulation minimum. The facility's maintenance engineer explicitly excluded motors with integral VFDs — the production line uses external Allen-Bradley PowerFlex 523 drives on the larger units, and the smaller motors run direct-on-line through a busbar distribution system.

INDASTRA sourced the replacement units from two manufacturers: WEG (W22 IE4 series, Brazilian origin, EU-stocked in Rotterdam) for the 2.2 kW and 4.0 kW ratings, and Leroy-Somer (DYNEO+ series, IE4 induction with copper rotor) for the 7.5 kW and 11.0 kW ratings. Both product lines matched the existing IEC frame sizes exactly — no shimming, re-drilling or coupling adaptation was required for any of the 84 units.

Installation and Commissioning

Replacement was carried out in two-shift batches to avoid a full line shutdown. The facility's own maintenance team handled installation. Commissioning time per motor averaged 45 minutes — the primary time-consumers were terminal box reconnection and bearing run-in checks. No motor re-winding, base modification or re-alignment was required. INDASTRA provided IEC frame dimensional drawings and wiring diagrams for all 84 units prior to delivery to simplify the installation planning.

Delivery was DDP Bursa from INDASTRA, with the WEG units arriving from Rotterdam stock in 8 working days and the Leroy-Somer units from a Paris-region warehouse in 11 working days. No unit arrived with transit damage; all 84 passed incoming visual inspection and insulation resistance testing (Megger at 500V, minimum 100 MΩ).

Measured Energy Savings

Electrical consumption on Line 1 was metered at the main distribution board for 30 days before and 30 days after the upgrade, using the same production schedule (same fabric weight, same loom speed, same shift patterns). The results:

• Before upgrade: 38,420 kWh/month (average across 30-day pre-period)
• After upgrade: 27,660 kWh/month (average across 30-day post-period)
• Reduction: 10,760 kWh/month (28.0%)
• Annual saving: 129,120 kWh/year
• Annual cost saving: Approximately €9,030/year at the facility's contracted industrial rate of €0.070/kWh (Turkish tariff including transmission charges)

The 28% reduction exceeds the theoretical efficiency delta between IE2 and IE4 (typically 3–5 percentage points) for two reasons: several of the replaced IE2 motors had degraded efficiency due to winding wear, and the facility had been operating some motors at high ambient temperature (38–42°C in summer) without derating — the new motors' Class F insulation and improved cooling fin geometry handle this condition without performance loss.

Payback Calculation

Total procurement cost for 84 motors (DDP Bursa, including INDASTRA sourcing fee): €127,400. Labour cost for installation (facility's own team, no external contractor): €8,200 estimated internal cost. Total project cost: €135,600. Annual saving: €9,030. Simple payback: 15.0 months. Adjusted payback accounting for the 30-day measurement period offset and Q3 2025 electricity rate increase: 14.2 months.

CO2 reduction equivalent (Turkey grid emission factor 0.432 kg CO2e/kWh): 55,780 kg CO2e/year — a figure the facility intends to include in its annual sustainability reporting to European garment brand customers who require Scope 3 supply chain data.

Next Steps: Lines 2 and 3

Following the Line 1 results, the facility's procurement manager has approved IE4 upgrades for Lines 2 and 3, covering approximately 170 additional motors in the 1.1 kW to 22 kW range. INDASTRA is currently preparing the motor inventory survey and sourcing quotation for the combined project, with a target installation window of Q3 2026.

If you are evaluating a similar motor upgrade project, INDASTRA can assist with motor inventory audit, analog matching, CE documentation, and DDP delivery to your facility across the EU, Turkey and MEA. Request a project consultation or use the motor catalogue to check IE4 availability for your specific frame sizes.