Can Solar Power Systems Generate Harmonic Distortion?
As more commercial and industrial sites invest in solar power, questions about its impact on power quality are becoming more common. Businesses want to know whether their solar system could be introducing problems into the electrical network — and what to do if it is. The short answer is that it can happen, but the reality is more nuanced.
What Are Harmonics and Why They Matter
In an ideal world, electricity flows in a smooth sine wave. Harmonics are distortions of that wave, caused by non-linear electrical loads such as variable speed drives, LED lighting, and some types of power electronics. While some harmonic content is normal and acceptable, excessive levels can interfere with how equipment operates and shorten its lifespan.
The key distinction is between the fundamental current (the main frequency your system runs on) and harmonic currents (multiples of that frequency). High harmonic currents mean more stress on your electrical infrastructure, even if your overall consumption remains the same.
Can Solar Power Systems Create Harmonic Distortion?
Most modern, grid-tied solar inverters from reputable manufacturers are designed to operate well within acceptable harmonic limits. In many cases, harmonic issues on a site with solar come from other equipment, not the solar installation itself.
That said, there are situations where harmonics become a concern. If the site’s load matches the solar system’s output — so very little power is being drawn from the grid — the percentage of harmonic distortion can appear high. This doesn’t always mean there’s a real problem; it depends on the size of the load and the actual harmonic current present.
In more severe cases, excessive distortion from other equipment can prevent inverters from synchronising with the grid because the reference waveform is too distorted. Large solar farms, especially those feeding directly into the grid, must comply with the national NRS 048 standard for power quality, and may require harmonic filtration before connecting.
How Harmonics Affect Your Equipment and Operations
Unchecked harmonic distortion can have costly side effects:
Overheating of cables, transformers, and other components
Nuisance tripping of circuit breakers and protection devices
Reduced lifespan of sensitive electronics
Increased transmission losses
Unexplained operational issues that seem to “fix themselves” when equipment is reset
These symptoms can erode reliability, increase maintenance costs, and, in some cases, affect safety.
How to Detect Harmonics from Solar Installations
Identifying harmonics requires measurement. Continuous recording using a power quality analyser over one to two weeks provides a complete picture of what’s happening. Handheld tools can also be used for spot checks when tracking down specific problem sources.
Measurements should be taken at the inverter outputs, on the grid supply, and at major loads. This approach helps confirm whether the solar system is contributing to distortion or whether other site equipment is responsible.
What to Do if You Suspect a Problem
If you think your solar installation is causing — or being affected by — harmonic distortion:
Arrange a professional power quality audit
Compare results to NRS 048 compliance requirements
For large-scale systems, assess whether harmonic filtration is needed
Focus on reducing levels to within acceptable limits rather than aiming for complete elimination
Harmonic mitigation can be costly, so the first step is accurate measurement to confirm what’s actually required.
The Alpha Power Solutions Approach
We carry out detailed power quality audits to identify the root causes of harmonic distortion and determine the most effective corrective measures. Our team uses sophisticated, high-speed power quality analysers, to record and evaluate the presence of harmonics, ensuring compliance and protecting both your equipment and your return on investment.
Taking Action Now
Harmonic distortion doesn’t need to undermine the performance of your solar power system. With accurate data and the right expertise, it can be managed effectively. If you want to know exactly what’s happening in your network — and whether it’s time to act — contact Alpha Power Solutions to arrange a power quality audit.
