interestingasfuck

That's the difference between making a light that can be seen over a large area vs lights to brightly illuminate a large area. Lighthouses only need to be seen not illuminate the sea.

But yeah, I would have guessed it to be higher as well.

I had a 100W LED that would put your eye out. Even with a fat heat sink and fan it partially burned itself. Kinda scary to deal with.

I'm guessing each LED is 200W?

Those fins are dissipating way more than 200W

Fresnel lense

Fresnel lense

Even for incandescent technology, the efficiency actually goes up with wattage, whilst for LEDs it's roughly the same (if I remember correctly, it mostly decays with temperature), so even for incandescent the gains in switching to LEDs actually fall as the original lamp wattage goes up.

Further, given the consumption of lighhouse lamps it makes sense that they had already been switched earlier from incandescent or similar, to the same kind of tech as street lights (i.e. some kind of high power fluorescent), which is a more efficient tech.

Last but not least there is one fluorescent technology (I'm not sure anymore if it's sodium vapor or if it is mercury vapor) that is (or at least it was a few years ago) more efficient than LED technology, but only really works well for very large lights (again, I roughly remember something like 1000W - so stuff like stadium illumination). At least in terms of consumption there is no point in changing from that to LED technology as it would be a step back.

So it makes sense that for some lighthouse lights they're not even replacing the lights with LEDs whilst when they do replace them the gains percentage-wise are a lot less than one would get from replacing one's 80W incandescent light bulbs with the equivalent modern LEDs (which would be maybe 12 - 15W).