LED Lights: Pros & Cons

By Phill Bertolus

Modern electronics has given us power saving LED lights. With carbon taxes being adopted world wide, reducing consumption of electricity is set to become a major driver in the adoption of the new technology.

So how hard is it to change over from the old incandescent light globe to these new frugal LED lights and what exactly are the benefits?

It's only in the last couple of years that LED lights have begun to hit the mainstream. While LEDs themselves have been around since 1962 their maximum light power has been very low. Their first applications where to replace indicator lights on panels of appliances (the ON light) and later in calculator displays (7 segment LEDS). In the 90's high power LEDS appeared on the scene, albeit expensively.

LED Lighting

Today a Google or Bing search reveals literally thousands of web sites that will sell you all kinds of LED lights that work inside and out, in the rain and under water, in hot climates and in the snow.

In the home, one of the biggest benefits of the LED can be had simply by replacing the old halogen down lights. Halogens typically consume 50 to 60 watts of power each. So when you see a room full of these hogs the total power consumption can quickly climb to several hundred watts. By replacing those lights with 10 watt LED types a power saving of 80% can be made.

So what exactly are the savings? Lets assume you have 4 power halogen hog lights in the kitchen. 4X60 = 240 watts. Let's round that to 250 watts. That's 1 kWh (electricity companies like to bill for kWh or kilowatt hours) every 4 hours. In Victoria the regulated electricity price is 19.0850 cents for the first 1,750 kWh and then a whopping 28.0500 cents for every one after that. So it's roughly $1 for every 5 hours of operation.

If we replace those halogens with 10 watt LEDs then we get 4x10 = 40Watts. Say 50 for good luck just to give the halogen hog a chance. That's still 20 hours of operation for every $1 instead of only 5 hours. Imagine if we could do that with the car!

Unfortunately, as things go, simply unplugging the halogen bulb and inserting that LED MR16 you just got off eBay is fraught with incompatibilities. You might be lucky and it just works. However, things could just not work. You won't burn the house down though so it's not dangerous, and because halogens are 12 volt devices, which get very hot, you're unlikely to electrocute yourself. Many of the old cheap electronic transformers electricians liked to install back then, can't work if the light doesn't consume enough power. Some do and some don't. The old iron transformers give best results, but if you're like me, who knows what's up there in the ceiling.

If you're out of luck, then you'll have to replace the transformers too. To overcome that, there are new GU11 type down lights that have their own transformers built in. If you're in this category, then an electrician is required to do the replacement. It is dangerous for ordinary humans to fiddle with the high voltage wires in the ceiling (the white ones which carry a lethal 240 volts).

Another category of lights are the bayonet type light globes. These guys can really chew electricity big time. One bulb can consume as much as 100 watts on its own. You can now buy 10 watt LED replacements which produce a reasonable amount of light, although a 100 watt globe is pretty bright. The bayonet type globes are very easy and safe to replace. I recommend getting a globe and trying it out in room first. If the light is OK then go ahead and replace all the globes in your house. The power saving are huge and will easily be seen on your power bills.

One of the biggest drawbacks of LED lighting, specially with cheap eBay type lights, is the propensity to interfere with televisions. Almost all websites fail to mention that the electronic circuitry housed in the end of the "globe" can emit radio frequency interference. Lights which emit low "EMI" (Electromagnetic Interference) cost more. Some lights comply to recognised international standards, but many do not. If you're unlucky and your TV antenna is close to a light, you can kiss goodbye to Channel 2 and Channel 7. As with all things, usually you get what you pay for when it comes to EMI.

Another gotcha is dimmability. Will the LED light work with a dimmer? Compact fluorescent globes can't, but some LEDs can. Dimmable LEDs generally cost a little more, but they are a direct replacement for those power hungry incandescent or halogen globes.

Good luck. You're now equipped to update all those old power hog lights and make some real savings.