Family Finance Help

If you were anticipating a typical “how to” piece, you know the type, long on bland verbiage and short on factual information that scarcely manages to argue the case suggested by the title, then you’re in for a let down (or an unexpected surprise, depending on your viewpoint). I really can’t be bothered and quite honestly I hardly need to write anything at all – the numbers say it all, so let’s get stuck in.

A typical mains powered halogen lamp (as commonly found recessed into ceilings) consumes 50 watts, can be purchased for about 2, lasts up to 2,000 hours, and will cost 12 to run for those 2,000 hours. The running cost is worked out using the standard rate of 0.12 per kWh and assumes modest average use of 3 hours per day which equates to roughly 1,000 hours per year.

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.

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.

To begin with, to compete against the lifespan of a single LED requires replacing the halogen 20 times, which brings the true purchase price up to 40 (20 x 2) which is nearly double the LED’s 24 price tag.

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.

Lastly, let’s also account for that “real” difference in purchase price; so over 40,000 hours a single halogen (plus its 19 replacements) will run up a bill of 280 but swapping it for an LED will instead incur a total of 43.20. Forget looking for 10% savings here or 25% there, we’re staring at the reality that halogen lamps are over 1000% (yes, one thousand percent) more expensive to own and run than equivalent LEDs.

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).

Needless to say, this illustration is somewhat low-scale and examines just one very lightly used light bulb. However, I noticed en-route from my North facing (hence gloomy) kitchen that 10 down lights stay on in there from early till late, then passing through the hall I spotted 4 more and here in my office 6 more are switched on for a good 6 hours daily.

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.

If we look at real life examples such as shops, offices, hospitals, hotels, airports and so on, where it is commonplace to use artificial light almost all the time then things get really interesting. Economics is little more than mathematics with currency symbols, and if we extrapolate our simple calculations above the numbers start to resemble seriously big bucks.

We have shown that it actually costs considerably less to purchase one “high priced” LED than to replace a “cheap” halogen lamp 20 times over to match the LEDs lifespan. We have also shown that the total cost of ownership for halogen lamps is 12 times that of their LED counterparts. So one has to ask: why would anyone NOT make the switch to LED?