1) How are LED light bulbs different to other types of bulbs?
LED light bulbs are the latest technology in the lighting world. They are more energy efficient than other types of bulbs, have longer lifespans, and allow you to be much more creative with your lighting design.
The humble LED has been around for a century, but for much of this time, it has only been used as an indicator light in electrical equipment (such as the power light on televisions). It took a Nobel Prize-winning effort to adapt the LED to be a viable lighting technology.
Once this was achieved, manufacturers could mount LED chips onto light bulbs as an alternative to traditional lighting. Where incandescent bulbs heat a filament to generate light, LEDs are illuminated by the movement of electrons in a semiconductor material. This provides many benefits, including longer lifespans, increased energy efficiency, and greater adaptability.
2) Can I use LED lights outdoors?
Yes, there are many different types of LED lights that are suitable for use outdoors.
The most important thing to remember when buying LED lighting for use outdoors is that they should have a suitable Ingress Protection (IP) rating. This rating tells you how protected the light is from the ingress of water and solid objects.
Outdoor lighting should have an IP rating of 44 or greater, as this will protect it from solid objects up to 1mm in size, and from splashing water. If the lights are situated in a position that is very exposed to the elements, they should have an IP rating of 65 or greater.
For more information about IP ratings, and why they're so important, see here.
In short, all smart lights are LED but not all LED lights are smart.
Smart lights are a subcategory of LED lights that allow you to connect your lighting network to your home Wi-Fi. By doing so, you unlock a whole host of features, such as the ability to adjust your lighting with your smartphone, set schedules and change the colour and/or colour temperature in an instant.
LED light bulbs can only be used in smart lighting networks if they have been specifically created for the purpose. Smart light bulbs are quite clearly marketed as such and are difficult to confuse with standard LED bulbs.
LED light bulbs do get warm, but nowhere near as hot as traditional incandescent bulbs. Incandescents generate light by heating a delicate filament to very high temperatures. As a result, the glass envelope of these bulbs get very hot.
LED bulbs work differently, and do not use heat to generate light, so they do not get nearly as hot. Like all electrical components, though, they do still generate a little heat, but not to the point where they are dangerous to touch. LED light bulbs will often have a heat sink built into them to divert any heat away from the delicate electrical components.
5) What are lumens?
Lumens (lm) are a measure of how much visible light a lamp or other light source emits, and they are the easiest way to determine how bright a light bulb is.
It used to be the case that wattage was the best indicator of a bulb's brightness. The rule was that the more power (watts) that goes in, the more light that will come out.
With the development of various energy saving light bulbs, including LED lighting, this is no longer valid. As they do not lose a lot of their energy through heat (as incandescents do) they are much more efficient and need much less power to generate the same amount of light. A 5W LED bulb, for example, can be just as bright as a 50W incandescent bulb.
This is where lumens come in. As lumens are a measure of a light bulb's output, rather than its input (as is the case with its wattage), it provides a more reliable way of measuring its brightness, and it also means you can compare the brightness of different types of light bulbs.
The higher the lumens count, the brighter the bulb. Standard household light bulbs can vary in brightness, but typically have a lumens count anywhere between 300-800lm. On the other hand, certain industrial-use light bulbs, such as High-Intensity Discharge (HID) bulbs, can have lumens ratings in the tens or hundreds of thousands.
6) Do LED light bulbs really save money?
Although their price is constantly falling, LED light bulbs still cost more per unit than other types of light bulb.
However, in the long run, LED light bulbs definitely will save money compared to incandescent bulbs, for two reasons.
Firstly, the energy efficiency of LED bulbs means that they use up to 90% less energy than incandescents to achieve the same level of brightness. This can bring energy bills down and save money in the long-term.
Secondly, LED light bulbs have an incredibly long lifespan compared to other types of light bulb. Where an incandescent light bulb might last for 1,000 hours, an equivalent LED bulb can last in excess of 20,000 hours. This means that for every one LED light bulb you buy, you would need to buy 20 incandescents to cover the same period. The unit price of LED bulbs no longer seems so expensive.
The vast majority of LED light bulbs are built to retrofit to existing lamps, meaning that they will fit in compatible fixtures. An LED light bulb with a standard B22d bayonet cap (BC), for example, will fit straight into a standard bayonet cap lamp.
You can see the wide range of available cap types here.
8) Are LED lights bad for you?
LED lighting emits greater levels of blue light than other forms of lighting, and some say this can have detrimental health effects. Research on the subject has been limited, however, so the exact effects (if any) aren't really understood.
A recent study published by the European Commission concluded that for LED light to have an adverse effect on your health, exposure levels would need to be ‘greater than those likely to be achieved with LED lighting systems in practice,’ meaning that the effect from normal household and commercial use is negligible.
Blue light has been proven to affect your sleep, however. It suppresses the production of the sleep-regulating hormone melatonin, which can cause fatigue and restlessness, which can lead to further health issues.
Smartphone displays and cool white LED lights that give off a lot of blue light should not be used right before bedtime, as this can stop you from sleeping. Instead, use warm white light bulbs, which emit a lot less blue light, and if you do use your phone in bed, turn on its blue light filter if it has one.
9) Do LED light bulbs work with dimmer switches?
Yes, LED light bulbs are compatible with certain types of dimmer switch. There are two types of dimmer switch: a leading edge and trailing edge. Most LED light bulbs are manufactured to be compatible with trailing edge dimmer switches, however, it's always best to check the manufacturer's specifications before you purchase to be sure.
Determining how many light bulbs you can use with one dimmer switch takes a little calculation. You can learn more here.
10) Do LED lights flicker?
When operating correctly, LED lights should not have any visible flicker.
If they are installed with an incompatible dimmer switch, LED bulbs may flicker unpleasantly. If this happens, you should check the compatibility of the light bulb with your dimmer and replace the bulb and/or the switch. See the LED dimming guide above for more information.