Normally you would expect an article like this to begin with some anodyne waffle by way of introduction before eventually getting round to presenting a vaguely plausible argument in support of the title. However, I don’t have the time right now and frankly don’t see the need either. The facts speak for themselves, so let’s start by assaulting you with a load of numbers.

A regular mains voltage halogen light of the type ubiquitously installed in ceilings requires 50W input power, costs about 2 to buy, will last maybe 2,000 hours and over that same period will use 12 worth of electricity; this is calculated by assuming very modest annual usage of 1,000 hours (about 3 hours each day) and the currently accepted average electricity price of 0.12 per kWh.

An equivalent GU10 format LED (in other words a quality LED such as Sharp’s Zenigata that is functionally almost identical) requires just 4W and will run for 40,000 hours or more; the purchase price is at the moment 24 but over 2,000 hours it costs just 0.96 in electricity to run.

At first sight it would appear that the LED costs way more simply because it costs so much to buy in the first place. But let’s look more closely at this picture to uncover the “real world” perspective.

For a start, the longevity of the LED is such that the halogen lamp will need to be replaced 20 times – that’s 20 x 2 which means that the purchase costs (plural) for the halogen are in fact 40 against 24 for the LED.

Secondly, if we run our comparison using the life span of the LED instead of the woefully short-lived halogen we see that where the LED uses just 19.20 worth of electricity, the halogen burns its way through 240.

As a final step, let’s now add together the running costs over 40,000 hours with the “real” purchase prices, and immediately it’s clear that the total bill for the LED will be 43.20 as compared to 280 for the halogen lamp (and its many replacements). If you thought this would be an exercise in scraping out 10% or even 50% savings, think again – the numbers do not deceive, halogen lamps cost 1000% more than LED equivalents.

Even when the purchases prices are accounted for, halogen lighting is still over 700% more costly. Halogen lamps appear cheap because each costs relatively little to buy, but the truth is they actually end up costing twice as much as an LED because of the frequent replacements, and they are massively more costly to run. LED’s are a completely different ball game and interestingly sometimes cost more to buy than to operate (as this example illustrates).

Of course, this is a very scaled down example applied to one little-used light bulb. I have just walked from my North facing kitchen where 10 down lights are almost permanently on from 7:00 A.M. to midnight, thru a hall with little natural light and 4 more halogen lamps, into my office where a further 6 glow maybe 6 hours a day.

Totting this lot up we can see that even these 3 rooms use more than 100,000 hours worth of electricity each year (that’s ((6*6hrs)+(10*17hrs)+(4*17hrs))*365 days = 100,010 hours) which works out at (100,000 * 50W * (0.12/1000)) 600 just in electricity costs for halogen lighting, compared to a rather more reasonable 48 for LED lighting.

Take a few more practical examples – offices, shops, hotels, hospitals, airports, the list goes on – where artificial lighting is on almost constantly; throw in some currency symbols and suddenly mathematics mutates into economics and we’re looking at eye-watering sums of money.

We have demonstrated that, despite initial appearances, the purchase price of an LED is about half that of an equivalent halogen lamp when you account for the repeat-purchases as it wears out. We have also calculated that overall electric lighting using halogen lamps is 12 times more costly than replacing them with LEDs. So the one question remaining then is this: why would anyone stick with halogen lamps?