On Wed, 09 Apr 2008 18:45:28 +1200, Terry Given
wrote:

Jay Ts wrote:
Smitty Two wrote:

Terry Given wrote:


these are great, they look fantastic, unity power factor, dimmable, and
last 50,000 hours.

Yeah, and they're only $145 each:

http://www.lampsplus.com/products/s_lr6/


And only 650 lumens, which is less than a 60 watt incandescent (890
lumens). I'm using 4 27 watt (100 watt equivalent) 6500K CFLs to
light my work room, so to replace them with those LED bulbs, it
would cost ... oh, forget it, I don't even want to do the math!
No way.

and how many lumens come out of your fixture with the 890 lumen lamp in it?

CFLs are terrible for that. they are measured in the light sphere sans
fixture, which can make a tremendous difference. easily 20-30%.


Oh, and the LR6 bulbs are spotlights, which is a no-go just by itself.
And they aren't daylight balanced (5500-6500K), another definite no-go.


they are not bulbs. They are light fittings with integral lamps. that
alters the C-B calcs substantially.

I think it's still going to be a while until 100-watt equivalent,
daylight balanced LED bulbs are available with an "ouchless"
startup cost, and I'm not holding my breath waiting. Just hoping
that it will happen, and won't be awfully long.

Jay Ts

its a total cost of ownership thing. efficiency wise they pay for
themselves (I have seen the ROI calcs but cant recall them) in a few years.

the main market is for people who dont change their own lightbulbs (eg
companies) where it costs a lot to get a single lamp changed, so they
often get a sparky to change all lamps whether or not they need it, eg
annually or bi-annually. And if its in say a tall atrium and you need
scissor lifts, these things pay themselves off in less than the
lifgetime of a single incandescent, CFL or flouro.

Cheers
Terry

For street lighting, warehouse lighting, and industrial lighting there
is a competing technology: Induction lighting. Typical lamp/bulb life
50,000 to 75,000 hours. Twice the life and better luminous efficacy
at a 50% surcharge compared to HID lighting. It is starting to get a
lot of notice. Oh, and better electrical efficiency, takes about half
the power for the same amount of light.