Case Study: Energy Savings with Onics Passive Neutral and Ground Harmonic Filter
Dr. Howard Penrose Ph.D., CMRP of MotorDoc LLC recently published an independent case study on the energy savings generated by the Onics Passive Neutral and Ground Harmonic Filter. The findings in this report are consistent with results from both commercial facilities with lighter three phase loads and industrial facilities with larger three phase loads and provide a visual case study regarding power losses due to neutral and ground harmonics.
Key Findings:
Direct energy savings of 12.7% tied to Onics Passive Neutral and Ground Harmonic Filter installation
Harmonic conditions in the neutral cause energy losses
5th and 7th (negative and positive sequence) harmonics can contribute to energy losses
After 2.5 months, the overall value of current in the neutral dropped to less than half of the original findings with an almost-perfect sinusoidal waveform (23 Amps —> 11 Amps)
Case Study Details:
Facility Profile: Electrical Engineering Motor Repair Shop
Onics Passive Harmonic Filter installed on primary lighting panel feeding VFD,
Data captured with the Empath ECMS-E1 Monitoring system and verified by Dr. Howard Penrose
Abstract: Energy Savings with Onics Passive Harmonic Filter
Dr. Penrose offers an insightful abstract of the case study:
It is established that neutral and ground harmonic content will load transformers and systems. Prior work has been limited as to the direct relationship of this additional loading on power consumption for a facility. Over the past 24 months, applied research has been performed on the measured impact of neutral and ground harmonics and energy consumption in commercial and industrial facilities.
In this paper we will discuss the application of an Onics Neutral Harmonic Filter in a single panel at a facility and the change in energy consumption before and after installation, as well as changes over a two-month period in similar loading conditions. Data collection for comparing neutral harmonic content was performed with an EMPATH (TM) data collection system.
Conclusion: Onics Passive Neutral and Ground Harmonic Filter Drives Energy Savings
Through the case study, the electrical engineering motor repair shop was able to tie a direct energy savings of 12.7% to the installation of the Onics Passive Harmonic Filters. These savings are further justified by a recent peer-reviewed technical paper published in the NETA World Journal outlining power losses due to neutral and ground harmonics.
By installing the Onics Passive Harmonic Filter, the facility was able to mitigate those losses significantly within 24 hours (as shown above.)
Before installing the Onics Passive Neutral and Ground Harmonic Filter, neutral current was measured as ~23 Amps on peak with significant harmonic content present in current.
Upon installing the Onics Passive Neutral and Ground Harmonic Filter, neutral current was measured as ~21 Amps on peak with a noticeable reduction of harmonic content in current.
After 2.5 months, neutral current showed a near-perfect sinusoidal waveform with a peak current of ~11 Amps. Harmonic content in 7th, 9th, 11th, and 13th were eliminated, and all other current remained at multiples of the 3rd harmonic.
Additionally, the research indicated that 5th and 7th (negative and positive sequence) harmonics also contribute to neutral energy losses when the values are unbalanced outside of theoretical expectations.
Once the Onics Passive Neutral and Ground Harmonic Filter was installed, the overall value of current in the neutral dropped to less than half of the original findings (23 Amps —> 11 Amps) and high level harmonic waveforms were significantly mitigated and/or eliminated entirely.