On Thursday, May 30, 2019 at 1:36:48 PM UTC-4, Jeff Liebermann wrote:

Maybe. LED's are certainly more efficient.
Lumens/watt
LED 100
CFL 60
Incandescent 16
For equal amounts of light output (lumens), a CFL lamp takes 1.7 times
as much power to produce that light as does an LED. That's a big

I doubt that's true. Flash power, the first 3 seconds of operation for an LED, might be 100 lumens per watt, but I think 60 is more realistic.


LED and CFL. For radiation loss, the surface area of a CFL lamp is
larger than the equivalent LED, and is therefore a more efficient heat
radiator. While the LED might waste fewer watts than the CFL light
heating up the room, the CFL will remove the heat from the lamp more
efficiently because it has a larger surface area. The LED compensates

I'm not sure that's the case. Surface area makes a difference for both radiation and convection, but the temperature difference is what really drives the heat transfer. The plastic globe area of an LED equivalent lamp runs much hotter than the curlicues of a CFL. (I haven't measured, but that's what my fingers tell me when changing both while hot.) (and that's probably because an LED doesn't have vacuum inside the globe, it has air that's in contact with the emitters)

I don't think the majority of the heat dissipation from a CFL is from the curlicues. But if even a portion is, then the orientation will make no difference. Air will flow through them base up or down about the same.