The Problem
Refineries and processing facilities are dense with harmonic-producing loads: SCR-controlled process heaters (1–20 MW each) at medium voltage, VFD-driven compressors, and large rectifier systems. The harmonic distortion from these MV loads propagates through step-down transformers to the low-voltage distribution network — MCCs, auxiliary pumps, instrument air compressors, building HVAC, control room power, and the hundreds of 480V motors that keep the refinery running.
The consequences go beyond energy waste. Voltage disturbances can trigger Emergency Shutdown (ESD) systems, causing unplanned shutdowns that cost hundreds of thousands per event.
What Causes It
SCR heaters fire at varying phase angles depending on process temperature demands, creating a harmonic spectrum that shifts continuously. Unlike the predictable harmonics from VFDs, SCR distortion changes from cycle to cycle — making tuned passive filters fundamentally inadequate.
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ESD and fire & gas systems use sensitive relay logic and PLC-based controllers that can false-trigger on voltage transients. A single voltage sag during a large compressor start can propagate through the emergency shutdown hierarchy, causing a partial or full plant trip. The cost of a single unplanned shutdown is typically $635,000–$6,350,000. Clean power eliminates the voltage disturbances that trigger these events.
The Solution
HarmoniQ deploys at the low-voltage (≤600V) distribution level — MCCs, auxiliary systems, and building services. Its narrowband tuning technology samples 20,000 times per second and cancels the harmonic distortion that SCR heaters and MV process loads inject into the LV network.
A medium-voltage product (up to 14kV) is in development for direct deployment on large SCR heater and compressor circuits.
Handles the time-varying harmonic spectrum from SCR heaters that passive filters miss. Responds in under 100 microseconds, reducing THD below 5% and extending transformer, motor, and power electronics life.
Stabilises voltage during compressor starts and heater firing angle changes. Protects safety-critical systems — ESD, F&G, and DCS — from the voltage transients that cause false trips.
Corrects power factor from 0.72–0.85 to 0.98+, eliminating massive reactive power flows and freeing transformer capacity for operational expansion.
The Impact
| Metric | Before | After HarmoniQ | Improvement |
|---|---|---|---|
| True power factor (LV bus) | 0.78 | 0.98 | +25.6% |
| Voltage THD (LV bus) | 8.5% | 3.2% | −62% |
| LV electricity cost | $26,400,000 | $21,100,000 | −$5,300,000 |
Every facility is different. Our engineers will model the exact savings, deployment costs, and timeline for your specific site — get in touch for a site assessment.
Beyond the Bill
Clean power means fewer ESD false trips, fewer compressor motor failures ($380K–$1.3M per rewind), and extended transformer life. For facilities with co-generation, eliminating harmonic backfeed improves fuel efficiency.
A facility saving $5.3M annually avoids approximately 2,590 tonnes of CO₂ — supporting OGCI commitments and EU/UK ETS obligations.