Re: new LED torch (flashlight) bulbs more efficient?

From: Don Klipstein (don_at_manx.misty.com)
Date: 03/23/05 

Date: Wed, 23 Mar 2005 06:03:16 +0000 (UTC)

In article <jDD%d.16161$qB3.7822@chiapp18.algx.net>, Ron Tock wrote:
>ghbt wrote:
>
>> Do the new LED torches (flashlights) actually give more value for
>> money from the batteries ( in terms of illumination per cost of
>> batteries) than the previously developed small and bright xeon bulbs
>> or the older ordinary torch bulbs?
>>
>Big time. I have a single AA cell LED flashlight on my keyring that has
>had the same battery in it for a year and a half. Still burns bright
>and gets ised a lot. I have another LED flashlight in the house that
>uses 4 AA cells. Same set of batteries for over a year and still
>bright. Also used a lot. The LED bulb, IMO, is the best thing to
>happen to flashlights since their invention.
>
>You'll be amazed.

  Bigtime, but only when the batteries get weak. Incandescent bulbs,
including halogen, xenon and krypton ones, have efficiency decreasing with
input power about or even more than proportioantely. LEDs have lesser
efficiency decrease from decrease in power, sometimes outright mild
increase in efficiency from a mild to moderate decrease in input power.

  Let not ability of LEDs to handle weakening batteries better than
incandescents do be any indication of efficiency at full power -
additional evidence is required to support a claim of the LEDs being more
efficient than fully-powered incandescents.

 - Don Klipstein (don@misty.com)

Relevant Pages

  • Re: new LED torch (flashlight) bulbs more efficient?
    ... >> the batteries than the ... >> previously developed small and bright xeon bulbs or the older ordinary torch ... > efficiency of the little incandescent bulbs used in flashlights. ... > LEDs also have a characteristic that the more drained the batteries ...
    (sci.energy)
  • Re: new LED torch (flashlight) bulbs more efficient?
    ... > the batteries than the ... > previously developed small and bright xeon bulbs or the older ordinary torch ... efficiency of the little incandescent bulbs used in flashlights. ... LEDs also have a characteristic that the more drained the batteries ...
    (sci.energy)
  • Re: thoughts on new Canon compacts?
    ... In fact the very small Li-Ion wall plug chargers simplify your life. ... IMVAIO, flashlights are the last thing you want to use NiMH batteries in, you can rest assured that when you need to use it, the batteries will have self-discharged to the point that the run-time is very low. ... I do have several combo flashlights from Streamlight, that have both LEDs, and a xenon bulb with an adjustable beam. ...
    (rec.photo.digital)
  • Re: Circuit Design Q. - battery charger
    ... #2 - The Booster Circuit - I intend to directly use the circuit illustrated ... batteries fairly quickly, BUT I don't want to "fry" the batteries - hence, ... OR six LEDs depending upon the size/design of eachlamp I'll be making) as ...
    (sci.electronics.design)
  • Re: LED light results -- short
    ... Lighting efficiencies - Initial lumens per watt. ... HID lamps and ballast designs vary widely. ... simply lying about efficiency. ... Another issue seldom mentioned for LEDs, ...
    (rec.outdoors.rv-travel)