Every week I get the same email. Someone is quoting a street lighting project, they have three offers for "100W LED street lights" in front of them, the prices are all over the place, and they ask me, honestly, which one should I buy. It is a fair question, and my answer usually surprises them: stop looking at the wattage first. It is the least useful number on the entire datasheet.
What the 100W actually replaces
A 100W LED fixture takes the place of an old 250W high-pressure sodium light and uses less than half the power to do it. That is the reason it became the default size for collector roads, residential streets, parking lots, campus paths. Municipalities like it because the retrofit math works out. Same poles, same arm, about a third of the electricity.
But the "100W" tells you consumption, nothing else. Whether the road is actually bright enough, how long the fixture lasts before a crew has to climb a ladder, what the power bill looks like in year four. Those answers live in the rest of the datasheet, and that is where the real comparison happens.
Lumens first, driver second
The first number I read on any datasheet is luminous flux. A good 100W fixture today lands between 10,000 and 15,000 lumens depending on the LED efficiency. Two fixtures both labeled 100W can be 20 to 30 percent apart in actual light output. That is not a rounding error. It is the difference between a road you can read a newspaper on and one you have to squint at.
After lumens, I check the driver, because this is where cheap fixtures quietly lose their efficiency. The fixtures we build at Luxsky use an integrated driver rated up to 94.5 percent conversion efficiency. Less of the power turns into waste heat, the LEDs run cooler, and things last longer. Nothing complicated about it. It is a number you will never see in a marketplace listing, but you will see it on the electricity bill, every month, for a decade.
Color temperature decides how the street feels
3000K is warm and soft. Neighborhoods like it because it does not glare into living rooms. 4000K is the neutral middle, the safe pick for most urban roads. 5000K looks crisper and brighter, which is great for highways and industrial yards and a bad idea on a quiet residential street, where the residents will let you know.
If you are swapping out old HPS fixtures, tell people to look at 4000K first. It is the closest visual match, and it is the advice I give every single customer. In all the years I have done this, nobody ever complained that their street felt too warm. The complaints about blinding white light, those come in all the time.
About IP66 and IK10
IP66 means the housing keeps out dust completely and survives powerful water jets. Street lights sit through rainstorms, dust storms, and the occasional pressure washer, so this is not a luxury. IK10 means the housing absorbs a 20-joule impact. Hail, a thrown rock, a basketball, whatever. It takes it.
If a supplier cannot produce the test reports for these two ratings, treat the numbers as marketing. That sounds harsh, but I have opened enough cheap fixtures to know the difference between a tested housing and a copied spec sheet.
Fifty thousand hours, and what it means
Most decent street lights are rated 50,000 hours at L70. At that point the fixture is still running, it just puts out 70 percent of what it did when it was new. At 12 hours a night, that is about 11 years. We warranty ours for five years, and I would argue that should be the minimum for this product class. When I see a two-year warranty, the first question I ask is about the driver. A manufacturer who trusts their driver does not hide behind a short warranty.
Features that pay for themselves
I know, "smart lighting" gets thrown around a lot. Still, this is where modern fixtures pull ahead of the cheap imports.
NFC programming, for example. You set power levels, dimming curves, timing, all from a phone app. No opening the fixture, no climbing. On a project with a couple hundred poles, the labor savings alone are real money.
0-10V dimming. It is the standard control signal for street lighting. Your fixture talks to the control systems you already own, or the ones on your shopping list.
Timed dimming. Full power during rush hour, reduced output after midnight. On residential streets that takes another 20 to 30 percent off the energy use, and honestly, nobody walking a dog at 1 a.m. notices.
People skip these because they sound complicated. On a 200-fixture project, they are not extras. They change the payback math.
Optics and mounting: the part everyone forgets
A good fixture mounts flat, tilts 15 degrees up, or tilts 15 degrees down. That range matters because pole heights and road widths are never the same twice. And the optics, Type II, III, or IV, decide how the beam spreads over the asphalt. Great lumens with the wrong optics leaves dark stripes between poles, and then someone has to explain to the client why the road looks banded.
Ask the supplier which distribution fits your road before you talk price. If they ask about your pole spacing first, that is a good sign. If they go straight to a number without a single question, they are reading from a brochure.
How I size up a supplier
Datasheet before quote. No photometric data, no IP/IK reports, I am done with the conversation.
Get a sample, put it on a real pole, and measure it at night. A catalog photo tells you nothing. A fixture on an actual road tells you everything.
Ask how the driver is mounted. The driver is the most likely part to fail, and a modular detachable one, like what we use, means a ten-minute swap instead of replacing the whole fixture.
Warranty terms in writing. What is covered, what is not, how claims are handled. All of it.
Last word
Buying a 100W LED street light gets a lot easier once you read the datasheet like someone who has to live with the result. Check the lumens, not the wattage. Choose the color temperature for the neighborhood, not because the catalog photo looks nice. Ask for the test reports. And count what the dimming and programming save over the life of the project, because that is where the real money hides. The fixture sits on that pole for a decade or more. An hour with the datasheets now beats a year of regrets later.
