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.
The average mains powered GU10 halogen down light (as very commonly seen fitted into ceilings) can be bought for around 2, uses 50 watts of electrical power and has a lifespan of about 2,000 hours over which time it will have cost 12 in electricity to operate. This is based on the average price of 0.12 per kWh and having the light on for a mere 3 hours a day (which works out at close to 1,000 hours over the course of a year).
An LED replacement for the halogen lamp (a high quality, near identical performance product similar to the Sharp Zenigata for example) will today cost 24 but uses only 4W and lasts for over 40,000 hours, and over the same 2,000 hours runs up an electricity bill of 0.96.
Initially then it seems that the LED is the more expensive option thanks to its greater purchase price. But this picture requires a bit more “real world” context to reveal the truth.
First, over the full lifespan of that one LED you will have to replace your halogen lamp 20 times, so the purchase costs now look like 40 for the halogen lamp(s) versus 24 for the LED.
Additionally, if instead of comparing the two over the rather unimpressive lifespan of the halogen we use that of the LED (40,000 hours) then the LED costs 19.20 to run whereas the halogen lamp is a whopping 240.
Finally, let’s add back in the “real” purchase price differential and over 40,000 hours it looks like using halogen lighting costs us 280 whereas the equivalent LED instead costs 43.20. We’re way beyond projected savings of 10%, 20% or even 50% – the running costs of halogen lighting are over 1000% more than comparable LED lighting.
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.
Just this little lot therefore clock up between them slightly over 100,000 hours annually ((6 * 6 * 365) + (10 * 17 * 365) + ((4 * 17 * 365)) which would present a bill of 600 (50w * 100000 hours * (0.12/1000)) using halogen lamps, but instead comes in at a much more agreeable 48 with LED lights. And that’s just for these 3 rooms.
Let’s examine some slightly more real world examples where artificial light operates almost constantly (hospitals, hotels, shops, offices, airports etc). Stir in some currency symbols and presto, simple mathematics is transformed into economics and all of a sudden we’re talking really big bucks.
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?
