LED lights to save electricity

Re: LED lights to save electricity

Bob Russell — Thu, 20 Oct 2011 11:28:04 GMT

We have ordered a single Philips tube (daylight) so I will let people know how we get on. I have avoided the Chinese LED tubes on ebay for now!!!

Re: LED lights to save electricity

Rob Loxley — Wed, 19 Oct 2011 18:30:40 GMT

[quote user="Arlo Guthrie"] But I found the light from those bulbs either made people look like they may not be alive anymore (the 'cool' blue ones) or they were liberally coated in fake tan (the 'warm' yellow ones). I opted for the funeral parlour look in the end![/quote]

Another thing, with LEDs, if they don't quote the CRI (colour rendering index) it's probably not good!

Re: LED lights to save electricity

Robert Lowe — Wed, 19 Oct 2011 18:06:16 GMT

[quote user="Arlo Guthrie"]

That's a coincidence, Rob, thats exactly where I got the GU10s for a room in our house which doesn't have recessed downlighters. Found the service from that site excellent (quick delivery, and they swapped my bulbs without quibbling when I decided I didn't want the yellow ones).

But I found the light from those bulbs either made people look like they may not be alive anymore (the 'cool' blue ones) or they were liberally coated in fake tan (the 'warm' yellow ones). I opted for the funeral parlour look in the end!

[/quote]

Hi Arlo

Fake tan for me - we honestly couldn't tell the difference between them and our normal bulbs but maybe that's South coast living for you

Re: LED lights to save electricity

Arlo Guthrie — Wed, 19 Oct 2011 10:36:25 GMT

[quote user="Robert Lowe"]

We are gradually replacing the GU10 bulbs throughout the house with these. They are relatively warm coloured and light up immediately. I was fed up with halogen going pop frequently and we haven't had any issues with these. The brightness is definitely a 50W equivalent

http://www.simplyled.co.uk/GU10-Dimmable-High-Power-LED-20-piece-SMD-5050-320-Lumens-50-watts-equiv_AWMR4.aspx?1

The company also do a T8 fluorescent replacement but I haven't tried this yet for work[/quote]

Re: LED lights to save electricity

Bob Russell — Wed, 19 Oct 2011 09:57:53 GMT

Interesting difference with light output. This will probably be a significant factor. As we have up to 30 tubes running up to 10 hours a day the electricity cost is a factor but so is the hassle of changing tubes and with the difficulties and costs of disposal of old tubes there is a growing pile of old ones in our loft space! Turn up at the local tip with two or three and they dont worry but turn up with a great pile they become suspicious and think 'trade'. If we dispose of them as a commercial business the cost is eyewatering!

It may be that down lighters are the only place for LED's at the moment as far as economics are concerned but what a crazy world where as a vet I am thinking about fluorescent tube disposal!

Re: LED lights to save electricity

Ian Mostyn — Tue, 18 Oct 2011 19:44:16 GMT

[quote user="Arlo Guthrie"]I didn't know they made fluorescent GU10s till your post!

But I bought on the basis of comparison with halogen, because I don't like fluorescent lighting at home. Must say, curious as to whether fluorescent GU10s suffer the same problems as other fluorescent lighting - eg slow warm up time and flickery cold light.

[/quote]

They have been around for about 2 years now but it is only the last few months that the MR16's have become available ( 2 small thin pins). All of my halogens have been MR16 but I will be looking to replace them sometime soonish. Modern fluorescents are available in warm white and they certainly warm up quicker - often just 10 seconds. Not the instant of incandesant but much better.

Ian

Re: LED lights to save electricity

Arlo Guthrie — Tue, 18 Oct 2011 19:42:00 GMT

[quote user="Arlo Guthrie"] [quote user="Bob Russell"]The number of LED's varies especially with tubes on ebay[/quote]

Here are Halers on ebay - a bit cheaper than I thought, and they really are bright. Each unit has its own transformer, so you just need to connected it to the wire feeding the old downlighter, and Bob's your uncle:[/quote]

Sorry - I've only just realised I'm rattling on about something quite irrelevant! I just read LED and jumped in without realising you're not talking about downlighter replacements. Back in my box. Still, if anyone is thinking about LEDs at home, Halers are great.

Re: LED lights to save electricity

Robert Lowe — Tue, 18 Oct 2011 19:41:57 GMT

http://www.simplyled.co.uk/GU10-Dimmable-High-Power-LED-20-piece-SMD-5050-320-Lumens-50-watts-equiv_AWMR4.aspx?1

The company also do a T8 fluorescent replacement but I haven't tried this yet for work

Re: LED lights to save electricity

Laurence Webb — Tue, 18 Oct 2011 19:26:03 GMT

[quote user="robloxley"]

A 5ft T8 fluoro is typically 58W putting out 5200lumens lasting 10-20,000hrs

A 5ft LED tube putting out 1900lumens is about 25W and will last typical 40-50,000hrs

[/quote]So you're using less than half the electricity, but also getting less than half the light out of it with a higher capital cost. Doesn't sound like that much of an advantage! Mind you that is for something to directly replace a flourescent tube. How do they compare with replacing halogen downlighters?

I suspect that it may be a bit early to invest in these, other than for replacing broken fittings as the cost of bulbs is so high. Low energy bulbs used to be £10-£15 each but you can now get them from Tesco for 99p each.

Re: LED lights to save electricity

Rob Loxley — Tue, 18 Oct 2011 18:52:08 GMT

My impression is that the LED sellers will typically overestimate life and lumen output and underestimate the same for conventional fluoros; I look forward to being proven wrong... However, crunching some figures:

A 5ft T8 fluoro is typically 58W putting out 5200lumens lasting 10-20,000hrs depending on use pattern (e.g. http://download.p4c.philips.com/l4b/9/927922084023_eu/927922084023_eu_pss_eng.pdf ) so if run for 60hrs/wk would cost £18/yr in electricity (at 10p/kWh). Over 50,000 hours total cost would be £20 for 5 tubes and £290 in electricity.

A 5ft LED tube putting out 1900lumens is about 25W and will last typical 40-50,000hrs (e.g. http://download.p4c.philips.com/l4bt/3/334467/master_ledtube_ga_334467_ffs_eng.pdf ) so would cost £7.76 in electricity for a year. Over 50,000hrs life total cost would be £50 minimum for the tube, and £125 in electricity.

So time to recoup investment may be about 3-4 years depending on exact costs (and you'll still need to replace the LED tube, though prices will be lower in the future no doubt), after that ongoing cost saving is about 50% but the output is at best about half...

PS if you have electronic fittings you'll need to remove the ballast, otherwise just the starter.

Disposal costs, aircon costs and labour to replace tubes however will all be reduced with LED tubes.

Re: LED lights to save electricity

Arlo Guthrie — Tue, 18 Oct 2011 18:17:02 GMT

[quote user="Bob Russell"]The number of LED's varies especially with tubes on ebay[/quote]

http://www.ebay.co.uk/sch/i.html?_from=R40&_trksid=p5197.m570.l1313&_nkw=halers&_sacat=See-All-Categories

Re: LED lights to save electricity

Bob Russell — Tue, 18 Oct 2011 18:10:24 GMT

[quote user="Ian Mostyn"]

My only concern with LED's is that they aren't bright enough yet. They are certainly an interesting technology and I will eventually use them to replace my kitchen lights. What kind of light output are you looking at?

Ian

[/quote]

The number of LED's varies especially with tubes on ebay. The ones I am looking at are very expensive and have a lot more LED's. I am considering replacing one to see how it goes. A small amount of rewiring is required in the holder but a tame electrician is useful!

I will go into the details tomorrow but the tubes I am looking at have a 5 year UK guarantee.

Re: LED lights to save electricity

Arlo Guthrie — Tue, 18 Oct 2011 18:04:34 GMT

[quote user="Ian Mostyn"]But an equivalent compact fluorescent GU10[/quote]

I didn't know they made fluorescent GU10s till your post!

Re: LED lights to save electricity

Ian Mostyn — Tue, 18 Oct 2011 15:58:32 GMT

But an equivalent compact fluorescent GU10 fitting would cost £11 for 2 and would be 11W of electricity. It would still take over 30 years to get the cost difference back. Compared to a Halogen, definitely but the technology is not yet good enough or cheap enough to replace fluorescent lights.

Ian

Re: LED lights to save electricity

Arlo Guthrie — Tue, 18 Oct 2011 14:19:35 GMT

I've just replaced most of the lighting in my house with led downlighters. I used www.halers.com. Equivalent to 50watt downlighter; more importantly the yellower unit I've installed gives off a nice light, similar to a normal bulb (a lot of them give off a very clinical blue light or one that makes everyone look jaundiced). I think they were about £50 a pop, but guaranteed 7 years and use 8 watts. So between the electricity and replacement cost saving, I should be quids in.

Re: LED lights to save electricity

Ian Mostyn — Tue, 18 Oct 2011 14:17:48 GMT

I just haven't seen domestic type bulbs suitable to light my reception or consult rooms..... yet. I have done a bit of digging and I have found some £60, 15W LED lights that give out 1150 lumens. This is the same as an 18W 2 foot fluorescent tube that costs £2.50. The LED's should last twice as long (30,000 hours cf 15,000) but saving 3W of electricity will take over 42 years to break even. Technology is moving rapidly and I am sure this will improve in the next few years but I am not quite ready to jump to LED's yet.

Ian

Re: LED lights to save electricity

Rob Davis — Tue, 18 Oct 2011 13:54:00 GMT

[quote user="Ian Mostyn"]My only concern with LED's is that they aren't bright enough yet[/quote]

Have you seen some of the latest surgical LED lights? They are certainly bright enough and are supposed to last around 40 years normal usage! Unfortunately they are not cheap...

Re: LED lights to save electricity

Ian Mostyn — Tue, 18 Oct 2011 13:42:33 GMT

Ian