Energy efficient lighting for commercial premises.

[heatherw]

I did a quick search, but just found a small thread started by Ivan a couple of years ago which might be out of date now, so I thought I'd start a new one.

We own 2 shops, one of which has around fifty 4 foot fluorescent tubes, the other has around 25.  As you can imagine, they use a LOT of electricity which I am now trying to reduce.  We already have the thin ones (I think they're called T8) installed and I was wondering whether there are any especially efficient fluorescent tubes available and what else I'd have to change to be able to install them.  The fittings we have are in a suspended ceiling, each one hold 4 tubes, and I don't know whether they've invented any other fitting which will fit into the same space (presumably about 4 foot by 2 foot) which doesn't use fluorescents.  I've also been seeing things on ebay which look like tube shaped LED strips, and I was wondering how these work, whether they need their own fitting, as presumably they don't need ballast if they're LEDs.

While we're about it I have another question.  We also have dicroic lamps in the shop, some of which are 230w and which I have already changed directly for GU10 LEDs, and some which are 12V halogens with a transformer.  Can I change these directly for 12v LEDs or do I also have to change the fitting or the transformer?  And where would I get such fittings from? What do they look like?

[daftlad]

While we're about it I have another question.  We also have dicroic lamps in the shop, some of which are 230w and which I have already changed directly for GU10 LEDs, and some which are 12V halogens with a transformer.  Can I change these directly for 12v LEDs or do I also have to change the fitting or the transformer?  And where would I get such fittings from? What do they look like?

You can get the GU10 lamp holders separately so you can remove the transformer, wire straight into the GU10 lamp holder and fit the GU10 led's into the existing fittings, both GU10 and 12 volt MR16 are 50 mm diameter so they are interchangeable unless the lamp holder is built into the fitting.

Check the fluorescents have electronic ballasts (don't have a starter) if they do use a starter then change the ballasts for the electronic type, they are much more energy efficient.

I think if you fit led tubes to the existing light fittings then you would also have to change the ballast, don't know though?

peas

[dhaslam]

Do you have to fit all the tubes in the four tube fittings?       These multiple fittings  increase the intensity of light  but not the spread.    In my last  office I had to remove one  tube out of each twin tube fitting because  employees were complaining  that the  light was too bright and causing glare from white surfaces.

[brackwell]

I presume you have reflectors on the strips and keep them clean.

As dhaslam says perhaps you could reduce the general level of lighting and use GU10 LED spots in localised areas.

I have noticed recently that some shops have been using lower lighting at the front than back.

Definately get rid of the 12v halogens which go yellow and reduce output with time anyway. LEDs daylight white are great,stay that way and will pay for themselves many times over. One can buy different angles of beam of GU10 which can be used successfully eg 120 degrees for general lighting and 60 or 30 for more precisely directed lighting. For a given wattage if you half the beam angle you double the light intensity.

 With trial and thought you may use simply less lighting.

Ken

[heatherw]

I presume you have reflectors on the strips and keep them clean.

Ken

Good point.  Yes they do have reflectors and no it hadn't even occurred to me that they had to be cleaned.  The ceiling is so far away (3.5m) that it's hard to get to with our normal ladders, but I'll bear this in mind for maintenance this winter.

The ones in these fittings are switched so we can have half on or all on.  Normally during the day we have half on, but after dark we do need all of the lights on.  They are very annoying in that they direct the light downward with little spread, but I haven't seen another type of fitting for suspended ceilings.  The other fittings were too bright and I've unplugged half of the tubes.  I think we're more or less on the minimum light intensity now, So now I'm trying to get the actual bulbs more efficient.  My father's been going on about electronic starters now for a couple of years, but I didn't realise they were more efficient,  just that they don't need changing when you change the tube.  I'm a bit hazy about this so correct me if I'm wrong.

[quote daftlad]  You can get the GU10 lamp holders separately so you can remove the transformer, wire straight into the GU10 lamp holder and fit the GU10 led's into the existing fittings, both GU10 and 12 volt MR16 are 50 mm diameter so they are interchangeable unless the lamp holder is built into the fitting. [/quote]  Of course, that would be the easiest way to go about things.  That never occurred to me either, i was trying to make it more complicated.

This is great, anyone had any experience with the LED tubes?

[markp]

LED striplights are fast becoming a viable alternative where colour temperature isn't necessarily important. The ones I've played with simply require a live feed at one end and neutral at the other - a simple modification to most fittings. The light they produce is a bit more directional though, and they are incredibly bright to look at. Certainly for store rooms, display cabinets, etc they are probably worth looking in to.

Let me know if you want more info, I have a friend who's a lighting consultant who has been developing these lights for a few years.

[heatherw]

LED striplights are fast becoming a viable alternative where colour temperature isn't necessarily important. The ones I've played with simply require a live feed at one end and neutral at the other - a simple modification to most fittings. The light they produce is a bit more directional though, and they are incredibly bright to look at. Certainly for store rooms, display cabinets, etc they are probably worth looking in to.

Mmm, sounds as though LED stri`plights are still in their experimental phase.  Shame, I'd have liked to get some cutting edge technology intp the village.  In a couple of years we might be getting somewhere.

We tend to use warm white lighting, although some of the LEDs I bought were daylight, and I've been mixing them.  The daylight is a bit of a shock after warm white, but I'm slowly becoming accutomed to it.  It seems to be more difficult to decorate the shop windows effectively for some reason.

Lighting design might be a bit of overkill for our situation because I'm on a low budget and can't afford to change many fittings, although if it was going to payback in a couple of years it'd be worth it.  I'd really like to change everything, including the panels in the suspended ceiling which are supposedly insulated but you'd never notice.  I wonder whether you can buy 150mm thick panels - ours are 30mm max, and fibreglass with a vinyl facing.  I suppose they've been there for 20 years or more.

[wookey]

Read lux magazine for some useful info on commercial lighting. http://www.luxmagazine.co.uk/

Best flourescents are currently about as good as it gets. That means electronic ballasts and the latest thin tubes (I'm no expert on tubes). LEDs in the same format are just reaching the same efficiency and will soon pass it. However be aware that because the output (of LED tubes) is directional you also have to change all the fittings.

LED strips gives you all sorts of exciting new lighting options which will be more interesting than lots of high tubes, but overall efficiency will be much the same unless you work out ways of reducing the actual amount of lumens needed for adequate lighting (bring the lights down rather than having them 3.5m up?)

For the GU10 swaps you may be able to use the old drivers. In principle it's fine but some drivers won't work properly with LEDs because they are so low power that the drivers struggle to supply so little power. The efficiency of those drivers matters just as much as the 'bulbs' so it probably worth changing them anyway for decent ones.