'Low Energy' lamps

[Peter Copestake]

I'm sorry but I can't find the original post on this subject. It may have been on the NLE site.
David, I think, was saying that unless they were on for a long time low energy bulbs used more than the filament ones. I asked our ("green") energy suppliers and this is part of their reply, after saying that David would have been right for the earliest bulbs _

Luckily for us the CFL technology has moved on a lot over the past 5 years, which is why I can confirm that all the CFL bulbs we sell on the Good Energy Shop…:

· include electronic rapid start circuitry to make the lamp light in less than 1 second with virtually no flickering.

· reach their full light output in less than 30 seconds

· come in a range of warmer white colour tones more suitable for domestic use, and

· come in various shapes and sizes (for a full list go to http://www.goodenergyshop.co.uk/Lounge/ ... ng%20bulbs)


So, because these bulbs turn on quicker it means that as long as the light remains on for at least 6 minutes, it has already used less energy that its non-efficient incandescent equivalent.

Hope this helps,
Peter.

[Peter Copestake]

Since posting this message I have had the opportunity of using two monitors.
One, from the County Council available through the Library service here, measures what is going into the mains meter in and can measure whole watts. The other, borrowed from my electrician neighbour, is plugged into the mains sockets and appliances are plugged into it, is more sensitive, eg., as I write, it is showing that my BT broadband box is using .08 watts.

Neither of theses instruments show any surge in power consumption when switching on low energy bulbs. Indeed the more accurate one reads a slightly lower wattage than their rating when these are switched on climbing to 1 watt less than their rating when up to full brightness.

Since these results directly contradict what I had previously been told I thought I should pass them on.

Peter.

[ned c]

On a recent shoot in a remote area where the only power was solar and very limited I used these bulbs to shoot by with remarkably good results. The color temperature is marked on many of them (I used 5000K) but there is a second factor to take into consideration; the Color Rendering Index (CRI) which is an index of how accurately they reproduce colors compared with a standard. I used bulbs with 80% CRI and they worked well with good color rendition.

ned c

[Peter Copestake]

I am sorry to keep replying to my own post but I made a mistake when posting the second one through misreading the monitor. The BT broadband box is constantly using 8 watts not .08. This looks as if my whole post is rubbish but I have checked the bulbs again and those readings are correct.
Thank you for your input, Ned, but in the UK we are bombarded with statistics about leaving things on standby etc but no mention of how much new technology uses.
The latest conundrum is why our 37" plasma shows 10 watts on standby when the manufacturers (Panasonic) say it is 0.4.
As regards using them for 'filming' I tend to leave my camcorder on 'daylight' if there is any daylight coming in at all, and I find very little extra 'warmth' when low-energy lamps are lit, confirming your more technical information, I think.

[Dave Watterson]

I did wonder about the BT Router figure because these have long been regarded as relatively heavy on current (not that in real world terms 8 watts amounts to much.) Sky receivers also use more current on standby than you might think because they send power up to the transponder thingie in the satellite dish.

I took a look at lamps in a couple of superstores this week and found little useful information about their colour temperature or CRI. (The only common factor is every shopper muttering to her or himself "They say it is equivalent to 60 watts but I think it's more like 30watts.")

When they first came in to our shops I heard a figure of 10 minutes as the minimum time they should be kept on if they were to be cost-effective. In a kitchen that is fine for preparing a meal, but what about popping in to make a cup of coffee? Who takes 10 minutes to do that? Our staircase light goes on only when we are about to use the stairs and that takes seconds.

The other bothersome point can be radio interference. Some lamps - or strictly speaking the power-packs in their bases - interfere at high frequencies and others at lower ones. I guess building adequate suppression for both would take too much space or cost too much.

You can get dimmable low-energy lamps but they usually need a different type of dimmer switch ...

The real pain is that the signs are we will be pushed towards LED lighting in the next few years which means changing many light fittings around our houses. I have seen some good LED lighting but the shops mainly have those blue lamps which do not seem very bright to the human eye and remind me of those public toilets with lighting designed to make it hard from drug addicts to find veins to inject! Good LED lamps are expensive as yet, though the price will surely come down.

Dave

[ned c]

Some detailed info on CRI; plus an excellent resource on lighting in general

http://www.lowel.com/edu/color_temperat ... ified.html

ned c

[Arthur Bates]

Merry Christmas and a happy New Year to all. I have just replaced my fitted ceiling lights with LED lamps. These were six 50w low voltage quartz halogen bulbs each with its own transformer. They ran so hot that in one instance one scorched the beam. I have found 4w LED main voltage lamps that, although needing new holders, fit the existing ceiling fitting. I think there are two types, a white light and a softer yellow. I chose the latter as it gave a very acceptable smooth lighting, very suitable for computer editing and writing and such tasks. Wow! 24w to light the room rather than 300w. Snag, at present they cost a bomb. I haven’t got the bill yet but I think they are about £16 quid each but they run cold and last a very long time. Bread and water only after Christmas I fear. I now am thinking of replacing my four 150w. quartz halogen video lights that I use round my animation rostrum with LED lamps. I have seen reports of Lights with 120 LEDs and I think more powerful ones too both of which run off batteries but I am sure could be converted to mains. Does anyone have details of where they are obtained and for how much? The present 150w are so hot that I wish to replace them although the burns on my forehead are now healing well! Arthur Bates

[Geoff Addis]

I recently bough 6 LED lights, each having three rows of 18 LEDs, from ASDA. They are battery operated and provide a good, although a rather norrow beam output that is compatible with my other studio daylight temperature lamps. Cost: £6 each. Although bought for a particular project where space was very limited, they also are very suitable for providing illumination over the working area of the editing desk whilst not illuminating the screens - just as I remember working in broadcast video galleries!

Geoff