Thought Leadership

Seeing the light

By Colin Walls

I observe in the news that the US government is “catching up” with Europe and progressively banning the sale of traditional incandescent light bulbs. I do not really regard it as catch up at all. The law is pointless and is therefore just successful in squandering tax payers’ money by being enforced.

I really think that governments should just get on with governing the country and not mess with such matters. It is fine to ban dangerous products, up to a point, but light bulbs are hardly a major health hazard. Give us advice, by all means, but that does not seem to work in this case, so more force was applied …

We are told that old fashioned bulbs waste energy. This has some truth, but is not the whole story, as I wrote about here. We are also told that low energy bulbs are just as good and much more cost effective, which, if that were also true, would mean that you would be stupid to want the old fashioned kind. In the UK at least, they have even tried giving away low energy bulbs. Normally, in my experience, free food and free beer always taste best, but this does not seem to work for light bulbs.

People do not like low energy bulbs for lots of reasons:

  • Compact fluorescent lamps [CFLs] have a very “cold” color, which is not pleasing.
  • CFLs have a lag when they are switched on.
  • CFLs take some minutes to reach full brightness.
  • There are many concerns about the ecological impact of CFL manufacture and disposal.
  • LED and other lamp technologies have been prohibitively expensive.

However, the products are improving at a rapid pace and these objections are being eliminated, which is why I believe that the government should leave well alone.

One of the problems with all kinds of low energy bulbs is knowing what to buy. We are all familiar with the power ratings of incandescent lamps and can visualize 25, 40, 60, 100 and 150 watts of brightness. However, all the new bulbs have much lower wattages, so figuring out equivalents is hard. The best measure of light intensity is to talk about the light itself, which is measured in Lumens, and this is specified on the packages of all new bulbs. All we need to know is the actual brightness of traditional bulbs and here are the figures:

Watts Lumens
25      200
40      450
60      800
75     1100
100    1600
150    2700

The ultimate source of this data is EnergyStar, which is a US Government agency, but the numbers do feel about right to me.

Having moved house about 18 months ago, I have run into two lighting “issues”:

The first was a challenge. Although it is an old house, the kitchen had been refurbished and was fitted with an array of halogen down-lighters. There are 14 lights, all on one switch. At 50w each, that is 700w in one pop. I always joked that the rest of the town would go a little bit dim each time I turned on my lights. Eventually, I found the solution, which was to fit “plug compatible” LED bulbs. These new lamps have a nice warm color and are just as bright and responsive, but consume only 5 watts each. They were expensive, but have a claimed 20X lifetime over the older ones. Even if they only last 10X the time, they will easily work out cheaper long term without accounting for power savings.

The other matter is just interesting. The town where I now live has a number of areas that are illuminated with old-fashioned gas lights. These have recently been refurbished and updated to make them low maintenance and energy efficient. They provide very pleasant and effective lighting. I would be very interested to know what their power consumption actually is. Maybe this is the way forward?

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This article first appeared on the Siemens Digital Industries Software blog at https://blogs.sw.siemens.com/embedded-software/2012/03/02/seeing-the-light/