EC vs AC Fan Efficiency: How Much Energy Savings & Payback?
EC fans (brushless DC external rotor) typically achieve 30%-60% higher overall efficiency than traditional AC shaded-pole / capacitor-run fans. In 24/7 cooling applications, the higher purchase cost is usually recovered through electricity savings within 6-18 months.
Efficiency Comparison Table
| Item | AC Axial Fan (e.g. JF12038A2HBL/T-5) | EC Axial Fan (e.g. JF12038EHBL-5) |
|---|---|---|
| Typical overall efficiency | 25%-35% | 50%-65% |
| Power at equal airflow | 100% (baseline) | 40%-60% |
| Speed control | None (or voltage control with efficiency drop) | 0-10V/PWM stepless |
| Noise (at equal airflow) | Baseline | 3-8 dB(A) lower |
| Life (L10, 40°C) | 30,000 hours | 50,000-70,000 hours |
| Unit purchase cost | 100% (baseline) | 180%-300% |
How to Calculate Payback Period
Annual electricity savings = (AC power W − EC power W) × daily running hours × annual running days × electricity rate ÷ 1000
Payback months = (EC unit price − AC unit price) ÷ (annual electricity savings ÷ 12)
Case study: cabinet cooling, JF12038 AC 25W vs EC 12W at equal airflow, 24h/day, 365 days/year, electricity rate 0.8 CNY/kWh
Annual energy saved = (25−12) × 24 × 365 × 0.8 ÷ 1000 = 91 kWh/year
Annual electricity cost saved = 73 CNY/year
If the EC costs 80 CNY more than the AC, payback is about 13 months
For more EC fan models, browse the EC axial fan product list; for AC models, browse the AC axial fan product list.
Want us to calculate the payback period for your actual operating conditions? Send us the power, running hours and quantity, or contact us for a selection recommendation within 1 business day.
Frequently Asked Questions (FAQ)
Are EC fans always more expensive than AC fans?
Unit purchase price is typically 80%-200% higher, but in 24/7 continuous operation the cost pays back within 1 year through electricity savings. For 8-hour intermittent operation, payback exceeds 3 years, so switching to EC is not recommended.
Are EC fans noisier?
At equal airflow, EC fans are typically 3-8 dB(A) quieter, because brushless motors are more efficient, generate less heat, and can slow down to match actual load without designing for peak noise.
Can AC fans save energy by voltage reduction speed control?
Reducing voltage lowers airflow and power, but efficiency worsens and noise may actually increase. EC fans use electronic commutation with a flat efficiency curve during speed control - this is the fundamental difference.
Do I need to rewire when replacing AC with EC in existing cabinets?
JIEFENGFAN EC models accept 220V AC direct input (built-in rectifier + driver), compatible with AC fan wiring terminals for direct replacement, no extra power supply needed.
How much can I save switching to EC in 24/7 server room / storage applications?
For a typical 100-cabinet cooling scenario: AC total power 2.5kW vs EC 1.2kW at equal airflow. At an industrial electricity rate of 0.7 CNY/kWh, annual savings are about 7,000 CNY, with hardware payback in 1.5-2 years.