LED vs Fluorescent vs Gas lanterns

[AvPD]

I have a 4 watt fluorescent lamp that runs on 4 AA batteries (http://www.flashlightmuseum.com/flashlight_view.cfm?item_number=EV00224), and while researching luminous efficacy I was surprised to learn that fluorescent tubes were more efficient than (commonly available) LEDS. I've been trying to calculate how many watts a reflector LED lamp I recently bought uses, if I assume each of the 8 LEDS draws 40mA at 6V that equals 1.92 watts. If this is a conservative estimate it is fair bit more than I expected a LED device to use, and in addition it seems that there is less light generated per watt than yesterday's technology.

A small portable Primus gas lantern I have that runs on a 190g butane/propane canister can generate far more light but I suspect the run time wouldn't be too long on a high setting. Yet it may generate more light per dollar. For reference I can buy alkaline AA's at AUD$0.33 each and a gas canister for AUD$2.50.

It appears that the cheapest to run portable lantern technology for the amount of light generated is currently the fluorescent lamp.

 

[Post #90]

I think I read on here that newer LED emitters are now more efficient than flourescent lights.

 

[meuge]

I have a 4 watt fluorescent lamp that runs on 4 AA batteries (http://www.flashlightmuseum.com/flashlight_view.cfm?item_number=EV00224), and while researching luminous efficacy I was surprised to learn that fluorescent tubes were more efficient than (commonly available) LEDS. I've been trying to calculate how many watts a reflector LED lamp I recently bought uses, if I assume each of the 8 LEDS draws 40mA at 6V that equals 1.92 watts. If this is a conservative estimate it is fair bit more than I expected a LED device to use, and in addition it seems that there is less light generated per watt than yesterday's technology.

A small portable Primus gas lantern I have that runs on a 190g butane/propane canister can generate far more light but I suspect the run time wouldn't be too long on a high setting. Yet it may generate more light per dollar. For reference I can buy alkaline AA's at AUD$0.33 each and a gas canister for AUD$2.50.

It appears that the cheapest to run portable lantern technology for the amount of light generated is currently the fluorescent lamp.

LEDs are most efficient at low current. That's why a Cree XR-E will do ~85 lumens/350mA but will go up to 130 at 1A.

The Rebel100s and Seoul P4 U-bins get 100+ lumens at 350mA, which corresponds to roughly a watt (someone correct me) of power draw.

A 100-watt type CFL bulb will emit 2000 (?) lumens at a power draw of about 20W... and the larger tubes are somewhat more efficient.

 

[Gunner12]

LEDs currently can not get the same Lumen/Watt at the same drive current of fluorescent bulbs but at 3w and below, some of the more efficient LEDs will have better Lumen/Watt then the fluorescent bulbs.

Dealextreme has some cheap Cree and Seoul lanterns but the UI is pretty bad(You HAVE to click through every mode) and heat sinking is also bad.

:welcome:

 

[AvPD]

Dealextreme has some cheap Cree and Seoul lanterns

The site always times out but using Google cache I'm pleased to learn that they ship internationally for no extra cost and accept Paypal. Hopefully they'll upgrade or fix their servers in the near future.

 

[Daekar]

LEDs are most efficient at low current. That's why a Cree XR-E will do ~85 lumens/350mA but will go up to 130 at 1A.

The Rebel100s and Seoul P4 U-bins get 100+ lumens at 350mA, which corresponds to roughly a watt (someone correct me) of power draw.

A 100-watt type CFL bulb will emit 2000 (?) lumens at a power draw of about 20W... and the larger tubes are somewhat more efficient.

2000 lumens out of a 100W CFL? If they exist, I haven't seen them... I have a couple of 100W equivalent CFL bulbs I picked up at Lowe's, and they're more like 1200-1600 lumens, if the packaging is correct.

 

[mzzj]

I have a 4 watt fluorescent lamp that runs on 4 AA batteries (http://www.flashlightmuseum.com/flashlight_view.cfm?item_number=EV00224), and while researching luminous efficacy I was surprised to learn that fluorescent tubes were more efficient than (commonly available) LEDS. I've been trying to calculate how many watts a reflector LED lamp I recently bought uses, if I assume each of the 8 LEDS draws 40mA at 6V that equals 1.92 watts. If this is a conservative estimate it is fair bit more than I expected a LED device to use, and in addition it seems that there is less light generated per watt than yesterday's technology.

A small portable Primus gas lantern I have that runs on a 190g butane/propane canister can generate far more light but I suspect the run time wouldn't be too long on a high setting. Yet it may generate more light per dollar. For reference I can buy alkaline AA's at AUD$0.33 each and a gas canister for AUD$2.50.

It appears that the cheapest to run portable lantern technology for the amount of light generated is currently the fluorescent lamp.

Those 6" 4w T5 tubes are horribly inefficient. usually 25-35lm/w which is same as leds couple of years ago.
Single XR-E Q5/R2 led outputs same or bigger amount of lumens with only 1.5W of power.

 

[Lynx_Arc]

I have several single 4watt flouro battery lights and they draw about 300-350ma at 6v or about 1.8-2watts..... not 4watts. The advantage is even light without a bunch of optics and such.