Small solar faults become expensive habits

Stuart Spiers | 9-6-26

One of the biggest misconceptions in utility scale solar is that major problems arrive dramatically. An inverter fails. A site suddenly underperforms. Revenue takes a hit.

In reality, that is rarely how it happens.

Most expensive problems begin life as something much smaller. A connector that is running slightly warmer than it should. A recurring alarm that gets acknowledged but not investigated. A tracker issue that only impacts a small section of the site, so nobody feels the urgency to act.

Individually, they can seem manageable. Collectively, they have a habit of quietly becoming expensive.

After more than 20 years working in solar and large scale infrastructure, I can tell you this with confidence: poor performance usually whispers before it shouts. The challenge is that underperformance often hides in plain sight.

You might see a small dip in generation and assume it is weather related. Perhaps a component is operating within tolerance, but not quite where you would expect it to be. Maybe there is a fault that resets itself often enough to avoid becoming a headline issue. On paper, nothing looks catastrophic. But solar performance is often about patterns, not isolated events. This is where experience still matters.

Monitoring platforms are incredibly useful and data gives us a much clearer picture than we had years ago, but dashboards only tell part of the story. They do not replace engineering judgement or an understanding of how assets behave over time. Sometimes, the first sign that something is wrong is simply a feeling that a site is not behaving quite as expected. That instinct usually comes from seeing the same early warning signs hundreds of times before.

What worries me most are the issues that stay unresolved because they are considered “small”. A minor fault today may only be impacting a fraction of performance, but left alone for six months, twelve months or longer, the financial impact starts to compound. Add in repeat callouts, increased wear on equipment, or knock-on failures elsewhere in the system and suddenly that “small” issue no longer looks very small at all.

The highest performing sites are rarely the ones that never have faults. They are usually the sites where small issues are spotted early, investigated properly and resolved before they become habits. Because that is really what deferred maintenance creates. Habits. And expensive ones at that.

At Solar Group Utilities, we spend a lot of time looking for the things that do not immediately stand out. The subtle changes, recurring trends and early warning signs that can quietly chip away at performance long before anyone notices a serious problem.

The good news is that most major failures give you clues.

You just have to know where to look.

Because we care.

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