Replacing incandescent lamps with direct replacement LED versions is a relatively inexpensive way to reduce energy waste. But it leaves quite a bit on the proverbial table.
If the application is commercial or industrial, this is almost certainly not the way to go. And of course, it’s not a smart approach for new construction because all you need to do is choose complete LED fixtures/systems. That choice is usually the correct one for commercial or industrial upgrades, also.
For example, a commercial laundromat has eight ceiling fans running along the “spine” of the room. These are outfitted with light kits that have fixtures for four ceiling fan “light bulbs” each. The customer wants to reduce energy waste. One way is to replace all 32 incandescent lamps with LED retrofit lamps (about $10 each).
Cramming the 5V power supply into the tiny space provided by the neck of the lamp is accomplished with some engineering compromises. That’s one issue.
Another issue with the paradigm keeps the lighting about the same. You had 32 emitters of light, and you’ll still have 32. And they are mounted on those ceiling fans rather than arranged around the room. Is this layout optimal, considering where in the laundromat people need the light? It’s not optimal, so why stay with it? And why so many lights?
The fan light kit approach made it convenient to mount and wire the lights. But a kit was needed on every fan, to throw out enough light to provide adequate light at the folding tables. This, in itself, is a point of energy waste. And with LED you can eliminate that.
What if you removed those light kits entirely, and installed LED luminaires that are designed “from the ground up” to be LED systems? You can mount them on the walls or anywhere else that makes sense, not being confined to the ceiling fan light kit mounting scheme.
You can aim them for the desired lighting (those folding tables and also the vending machines). They will be a more efficient design in terms of power supply simply because there’s adequate space in the fixture to accomplish that.
Those retro lamps are fine for homeowners who want to make a few spots more efficiently lit and don’t want to invest in new light fixtures. But for applications of any scale, you need to rethink the entire lighting scheme from scratch.
These days, there is almost certainly a complete luminaire that not only saves energy and improves lighting, but also provides interesting opportunities for improving the aesthetics.