New Homes & Downlights

The greenest watt is the one you don't have to create. Energy efficiency is the low hanging fruit of greening our homes. Ask your questions or post your energy efficiency tips in here!

Re: New Homes & Downlights

Postby Tracker » Thu Jan 21, 2010 10:06 am

zzsstt wrote:Tracker, in an earlier post, suggested that the downlights using PL-C type fluoro's give a better result, so they might be worth trying.


Please - be sure it's warm-white ( That's us - Old dudes ) I do hate the sterility of Cool White.
Tracker
Solar Crusader
Solar Crusader
 
Posts: 5111
Joined: Wed Sep 23, 2009 5:54 am
Location: SYDNEY --- EA - Network, Retailer - EA

Re: New Homes & Downlights

Postby bradley.jarvis » Thu Jan 21, 2010 10:12 am

For led downlights we got ours from Jaycar (http://www.jaycar.com.au/productResults ... 8&form=CAT, we have the CAT. NO. ZD0349 but some of the others look pretty good. we have no affiliation with Jaycar). Just looking now they have a better range then when we bought ours a few months ago. Normal lighting stores seem to be a little overpriced for this stuff (when we were looking at a lighting store in Warragul they had led lights that were over $100 each). Jaycar have a good discount on higher quantities too. But as zzsstt suggests you should get some samples and try them out to see if you would be happy with the output. Everyone will have different views to what is acceptable.

When looking at led downlights I would personally stick with the small led count high output ones, keep clear of the 20-30 led per unit. Look and the 1-4 led Nichia, Luxeon or Cree. Look at the Lumen output the viewing angle and the power consumption. We have found with the led lights they have a removable lens which focuses the light, when removed you get a more spread light with less intensity.

The other place you could look for well priced led downlights is http://www.soanarplus.com . I believe they are linked to Jaycar somehow (they share similar parts including common part numbers, but cheaper. they may be a wholesale division with no shop front, but they do sell to the public). I am not associated with Soanar either, but I have bought stuff off them before and found them to be really helpful.

Thanks, Brad
Living off-grid and loving it!
bradley.jarvis
Solar Evangelist
Solar Evangelist
 
Posts: 80
Joined: Tue Sep 22, 2009 10:46 am
Location: Australia, Victoria, Trida

Re: New Homes & Downlights

Postby tonydav » Thu Jan 21, 2010 10:18 am

Thanks for that - this info's great. Having a look at Jaycar now. Prices for these LED lights are about the same as the Fluro ones I was looking at.

Need to work out some way to rig up a test system to trial these.
tonydav
Solar Supporter
Solar Supporter
 
Posts: 5
Joined: Thu Jan 21, 2010 6:49 am

Re: New Homes & Downlights

Postby Tracker » Thu Jan 21, 2010 5:32 pm

.
http://www.ledlighting.com.au/products-led.html

If you want to see innovation, then check out this site.

They comment that the highest power unit is currently 20W, but soon they will have 30W in stock.

I tend to think/agree, that LED technology is currently better suited to special applications like hall-ways, stairs, and personal mood lighting.. They are not quite at the stage of flooding a room.. Perhaps they never will. BUT - they can make for very soft Mood-Lighting (and the best security lighting).....
.
Don't forget the humble PLC flouro can be efficiently run from DC, so that those with Island Power (Stand-Alone PV power), can just use a switch=mode inverter to power a number of PLC tubes.
Oatley Electronics have brought out driver kit projects..
.
.
Tracker
Solar Crusader
Solar Crusader
 
Posts: 5111
Joined: Wed Sep 23, 2009 5:54 am
Location: SYDNEY --- EA - Network, Retailer - EA

Re: New Homes & Downlights

Postby zzsstt » Thu Jan 21, 2010 6:30 pm

And yet I still remain sceptical......

The Cree 9W LED is specified as equivalent to a 30W halogen, and this site has "4W" units that are light equivalent to 25W halogens?

Their cost comparison document quotes a 12V MR 16 halogen as costing $10 and with a life expectancy of 2000 hours. In reality they cost about $2.50 for a globe with a life expectancy of 5000 hours.

Their comparison is for usage 8 hours a day. That may be correct for use in a commercial environment, such as product lighting on a shelf, but for domestic usage? Even in winter I doubt that our lights are on for 8 hours a day, and in summer it would be more like 3 hours a day.

If you recalculate the cost comparison based on a 5000 hour lifespan and $2.50 cost for a halogen, what do you get?:

Their estimation of total cost over LED lifespan (of the full stated 50,000 hours) is $375 for halogen and $75 for an LED

Recalculated with $2.50 price and 5000hr life for halogens, the halogen total cost is $150

$150 for halogen vs. $75 for LED. Assuming that the LED last for the full 50,000 hours.... or 17 years at 8 hours per day usage ........ not so big a saving is it? Especially if the $40 LED unit dies after 5 years!

I have no doubt that LEDs will be good, once we get the price down, the technology right, and get rid of the hype! But at this point they seem a big gamble from a cost viewpoint!
zzsstt
Solar Crusader
Solar Crusader
 
Posts: 1296
Joined: Fri Oct 02, 2009 2:27 pm

Re: New Homes & Downlights

Postby Tracker » Fri Jan 22, 2010 5:05 am

.
zzsstt wrote:If you recalculate the cost comparison based on a 5000 hour lifespan and $2.50 cost for a halogen, what do you get?:


Not wishing to turn this into an open debate....

I would wonder which "Life Expectancy" is correct... The 5000 or 2000.
I am biased - from having to replace the rotten things. I would suspect that the first one might last the 5000, if all goes well when first "Inserted". Replacements will not last..
After the first one, the contacts WILL be weakened. ... And if the first one is not correctly aligned with the holes prior to pushing, the blade is bent and the self-destruct key is kicked in.

You NEVER call an electrician to change a light-bulb -- Do you? -- NO -- So you DIY !!!

The bulb is unwittingly replaced by the owner, and it fails in even less time.

WHY - those rotten blade contacts.. causing burning and final destruction of the globe.

I also find that prices do vary dramatically. I do find them in the specials bin for $2.50, but more often, the one I want is much more.

Who knows just how long LED lamps WILL last? We do know that their current is proportionally lower,
and we do know that there is a difference between the DESIGN life and the PRACTICAL life of halogens.

I am confident that is why newer bulbs use a twist-action and a contact-wiping action, than the abrasive-pinching action of the originals.

An advantage of LED - Low-Voltage lamps, is that they work best with a constant current source.
Thus, you can control groups of lights from the same source.. Only problem - One Out=All Out

I think that sometimes we must make a leap-of-faith, and make a choice, irrespective of cost.

When I purchased about the dozen PLC Downers (for Hall-Ways, Kitchen, Bathrooms), then were much more expensive that Incandescent Downers. I don't think that we have regretted the choice in the long run, unlike so many 50W halogen owners, who purchase on cost, only to find that they have a (sorry for the pun) , A Holey mess !

Anyway - no more from me on my pet lighting hate. I just repeat the opening question ..

Why do Architects & Builders continue to offer new homes full of Halogen Downlights?
Surely these professionals see the ongoing issues that these lighting products create in terms of energy efficiency!

.
Were I starting again... I would have no hesitation and , taking into account all the comments on Light-Distribution, Efficiency, Cost and Application, I would again use a varied combination of technologies from T5's to LED STRIPS..

Have fun - Do it and enjoy the result !
.
.
Tracker
Solar Crusader
Solar Crusader
 
Posts: 5111
Joined: Wed Sep 23, 2009 5:54 am
Location: SYDNEY --- EA - Network, Retailer - EA

Re: New Homes & Downlights

Postby zzsstt » Fri Jan 22, 2010 7:54 am

Tracker wrote:I would wonder which "Life Expectancy" is correct... The 5000 or 2000.


The "5000 hour" rating given to the halogens in question is - alledgedly - a reasonable middle ground for a life expectancy of between 2000 and 10,000 hours. The life of halogens depends greatly on the type of luminaire, a recessed fitting results in higher operating temperatures and can reduce the globe life. Equally a fitting exposed to moisture (or dirt) can cause the globe to fail prematurely. With regard to the contacts, the connectors used in MR16 halogen luminaires are, I have been told, classed as consumable items and should/can be replaced.

Tracker wrote:Who knows just how long LED lamps WILL last? We do know that their current is proportionally lower, and we do know that there is a difference between the DESIGN life and the PRACTICAL life of halogens.


And of course the "marketed" life bears no relationship to either the design life or the pratical life, for either LEDs or halogens! I must also say that given the need for lighting companies to keep making money, selling a product that will really last for 25 years could be viewed as suicidal....... unless, of course, they plan to release a new technology in a few years that will encourage or force people to scrap their LEDs in favour of something better?

Tracker wrote:I think that sometimes we must make a leap-of-faith, and make a choice, irrespective of cost.


Irrespective of cost is a big call, given the potential for loss, but I see your point. To me, T5's are a no-brainer, so that's what I used!
zzsstt
Solar Crusader
Solar Crusader
 
Posts: 1296
Joined: Fri Oct 02, 2009 2:27 pm

Re: New Homes & Downlights

Postby rg767 » Thu Jan 28, 2010 10:40 pm

The hour rating of any lamp is defined like this:

Hour rating = operating time at which 50% of the same batch of lamps will have failed.

Now, to stir the pot - the average lighting energy use used to be (and may now have changed) 4% of the average energy use of a house.

Does energy efficient lighting matter at all?
rg767
Solar Crusader
Solar Crusader
 
Posts: 468
Joined: Sat Jan 02, 2010 7:22 pm

Re: New Homes & Downlights

Postby zzsstt » Fri Jan 29, 2010 6:33 am

rg767 wrote:The hour rating of any lamp is defined like this:

Hour rating = operating time at which 50% of the same batch of lamps will have failed.


Nearly.... In fact it is the operating time at which 50% of the same batch of lamps ARE PREDICTED to have failed.

This is my big concern with LEDs in particular, the life expectancies are entirely theoretical. The manufacturers can predict a life expectancy of 50,000 hours until they are blue in the face, but the reality is that we do not know how long they will last. I have previously recounted the story of a batch of computer related products that I used, that all failed after 12 -14 months even though they had a massive stated MTBF. Equally many people have seen the "cheap" eBay LED's fail very quickly, and in my experience CFL's (I have been using these since their inception) whether cheap or expensive rarely last more than a couple of years. I also notice that Philips have now reduced their CFL life expectancy from the original 7 years to 3, presumably based on the fact that their original "theoretical" life expectancy turned out to be a gross overestimation!

rg767 wrote:Now, to stir the pot - the average lighting energy use used to be (and may now have changed) 4% of the average energy use of a house.

Does energy efficient lighting matter at all?


Only if everything else has already been done! As I pointed out earlier in the thread, making one less cup of coffee will save more energy than replacing a 12V halogen with an LED - and that's on straight "directly used energy to boil one cup of water", it doesn't include the embodied energy of the LED or it's transport costs etc.

But it's an easy sell to the uninformed general public - "buy new lights and save the world" - and fits beautifully with the profit driven nature of AGW. Telling people to make less coffee just reduces the profits of the coffee companies, which is not the idea at all. Indeed the ultra cynical view would be that making a profit selling a product that will not really reduce power use is an ideal solution - the consumer feels good, the lighting manufaturer and retailer make money and the energy company doesn't suffer at all! Perfect!
zzsstt
Solar Crusader
Solar Crusader
 
Posts: 1296
Joined: Fri Oct 02, 2009 2:27 pm

Re: New Homes & Downlights

Postby bradley.jarvis » Fri Jan 29, 2010 8:24 am

Unfortunately being efficient and long life is not in the interest of a capitalist society. However competition will drive qualities such as these over time (only if people buy good quality).

The life of a LED will depend a lot upon the environment they are subjected to (very important to drive them at the rated specification including temperature which needs to be taken into account, since most LED datasheets will show that they can't handle as much current when hotter). The trick is to find a product that is made by a company that has a reputation they want to protect, they have more interest in selling a good product that people are happy to buy and more importantly recommend to friends.

There is more than just hype that LED's are being used, I would say that they have a longer life than halogens, look at traffic lights for instance. I know that Vicroads have a pretty tough testing criteria (they were quite reluctant to start using LED technology at first), yet pretty much all traffic lights are now LED. Also most trucks now have LED tail lights, instead of cheap filament globes.

Thanks, Brad

PS. With boiling water, we boil enough for current use plus an extra amount to fill a thermos. The thermos water can be used for the rest of the day or the next morning and still be quite warm. It saves more energy than just boiling one cup(as long as you use the thermos water) because you only heat jug once. This is good if you have a couple of hot drinks a day. We started doing it when we had to unfreeze mash for when our child started eating food, we took the ice cube of mash out of the freezer, put into a little cup and then put into a small bowl of water from the thermos.

Our water is mostly boiled on our combustion stove (we do use a gas burner every second day when its warm) which runs off wood collected from our property. More trees are growing than we use too.
Living off-grid and loving it!
bradley.jarvis
Solar Evangelist
Solar Evangelist
 
Posts: 80
Joined: Tue Sep 22, 2009 10:46 am
Location: Australia, Victoria, Trida

PreviousNext

Return to Energy Efficiency

Who is online

Users browsing this forum: No registered users and 3 guests

new solar power specials