In refrigeration lighting systems, the driver is often treated as a “background component”. But in reality, it directly affects energy consumption, thermal load, and even long-term operating cost.
One of the most important things to understand is that driver efficiency is not a fixed value — it changes depending on how the driver is used.
1. More Drivers Doesn’t Mean Better Efficiency
In many store installations, lighting systems are designed in a distributed way, meaning multiple drivers are used across different shelves or sections.
This approach is flexible, but it comes with a hidden cost.
Every driver consumes a small amount of power by itself, even when the load is low. So when the number of drivers increases, total system losses also increase — even if the LED load stays exactly the same.
From a system point of view, this is something that is often underestimated.
2. Efficiency Depends on Load
Like most switching power supplies, a driver is not equally efficient under all conditions.
It has an “ideal working range”, where efficiency is at its best. When the load drops too low, the fixed internal consumption becomes more significant, and overall efficiency starts to decrease.
In real supermarket applications, this situation happens quite often, especially in:
- modular shelf lighting
- partially loaded cabinet sections
- retrofit projects where load is not fully optimized
So the real efficiency you get in the field is not just the datasheet number — it depends heavily on how the system is designed.
3. Example – Efficiency Behavior
A good reference here is the Mean Well XLG-75-24 series, which is widely used in industrial lighting applications.
The chart below shows its efficiency trend under different input voltages and load conditions (tested at Tcase 75°C).
