Worth sharing this, over 250 Lumens per watt at 4400K (nice neutral white)...
http://www.cree.com/news-and-events/cree-news/press-releases/2012/april/120412-254-lumen-per-watt
Worth sharing this, over 250 Lumens per watt at 4400K (nice neutral white)...
http://www.cree.com/news-and-events/cree-news/press-releases/2012/april/120412-254-lumen-per-watt
Lance
What are the lumen per watt figures for each of:
(a) old incandescent e.g.60Watt globe
(b) old fluoro tube e.g. 40W (36W) tube
(c) compact fluoro "bulb" e.g. 12W
(d) halogen downlight e.g. 50W
(e) LED bulb costing ? $30 that replaces a 60W incandescent
Using Wikipedia as a reference, with some rounding
http://en.wikipedia.org/wiki/Luminous_efficacy
Old incandescent 15 lm/W
Old fluoro T8 80 lm/W
New fluoro T5 100 lm/W
Compact fluoro 60 lm/W
Halogen downlight 20 lm/W
LED bulb 60 - 100 lm/W
Thanks gg
Also for the excellent link !
LED Street lighting is running @ 100-150 lm/W. So mass production LED lighting is making great gains.
200 L/W for a LED fluoro replacement from Philips, supposedly on the market in a couple of years:
Lance said:
200 L/W for a LED fluoro replacement from Philips, supposedly on the market in a couple of years:
I remember when the first CFL was released, the Philips SL18 (I still have one). Philips took more than 3 years to release the product is Aus. We are a very small market so we don't mater to the big players.
Have replaced a 36W flouro tube with a LED bar (18W) and it is just as bright as the old one so must be about 200L/W
No, there's nothing that efficient on the market as yet, the average LED fluoro replacement is 80 to 100 L/W at the moment. I have done the same, replaced an 18W tube with a 10W LED and it's at least as bright.
There's 2 reasons for this. Firstly, the LED tube throws all the light downwards where you want it, a fluoro tube throws half its light into the fitting reflector, where some of it is absorbed as the reflectors are usually just white paint.
The other reason is that the tube you replaced was most likely a cheap halophosphor tube and their efficacy is nowhere near the "best case" 100 L/W of a really good fluoro.
Two guys were walking around the school where I work working up a quote to replace all the flours with LED replacement. They were saying your 36 watt flouro draws 40 watt if you count the ballast. Their LED replacement draws 18 watts. Most classrooms have 800w - 1kW load of lighting, there are 45 classrooms so the potential energy saving is big. I wonder what the cost will be and the consequent payback period. Will keep you posted.
I've done 2 audits at primary schools (WA) Greg and can vouch for what you say - 500W for a small classroom and 1kW for a bigger one - all with T8 fluoros. At the 2 schools I did one used 50% of energy on lighting and second was 35%. Spending over $10000 per year on lighting. Across all the WA schools that will really add up - I'd like to talk to WA dep't of Ed about a state wide program to upgrade all schools - if the LED vendors haven't already tried it.
Cree have just released these, probably 120V only at the moment although it doesn't say on the site of datasheets, but have emailed them anyway. Oh, and they RRP for $10-$14!
They are fudging their figures quite a bit, they list their 900 lumen bulb as a 100 watt equivalent, but a 100 watter normally puts out around 1600 or so lumens, so really theirs is a 60 watt equivalent at best. They are probably working on equivalent lux figures, as their bulbs are directional and so if used in a regular hanging pendant fitting, the top third or so of the room will be in shadow.
It's things like this that are giving LEDs a bad name, and shows a lack of understanding on the part of the seller.
We need to replace all lighting in the house and shed, with LED lighting. I see Phillips don't have a complete range, and we would prefer to buy from Australian manufacturers, if at at possible.
Can you please advise where we can buy our LEDS ? We have a fair range, 40 watt, 60, 100, fluro tubes, some really small ones, etc,etc.
petemoss said:
Can you please advise where we can buy our LEDS ? We have a fair range, 40 watt, 60, 100, fluro tubes, some really small ones, etc,etc.
I doubt there are any Australian "manufacturers", maybe there are a few Australian "badge engineers". Anyone else?
If you want an honest retailer with a big range, you could do worse than to start here: http://ledsales.com.au/
Lance said:
They are fudging their figures quite a bit, they list their 900 lumen bulb as a 100 watt equivalent, but a 100 watter normally puts out around 1600 or so lumens, so really theirs is a 60 watt equivalent at best.
Lance, here is a reply from iGlobe, after I questioned them in regards to the lumens ..
"Now about the luminosity. A 100 watt incandescent for a majority of its life sits at or around the 900-1000 lumen mark depending upon brand and other factors. We use these equivalent measures because this is what people will notice as a fair comparison. What must be noted is LED technology is instant at maximum light output, and doesn't have the light degradation over life that incandescent lighting does."
They also stated that their products are not Australian made, they are made in China.
johnmath , thanks for that link. Would be great if there was a 'sticky" thread somewhere about LED lighting, links to reputable suppliers, number of lumens per watt (min), what to look for, etc, etc.
There is a Australian brand, Grinlites. but made in China. Check them out for the lights you may need.