LED stands for Light Emitting Diode.  It is a semiconductor light source that produces light when a current is passed through it.  This process is called electroluminescence. 

LED technology was invented in the early 20th century and the first practical use of visible spectrum LED light was developed in the early 1960s. LEDs were originally only available in low-intensity red but they have been developed since this time to now produce a high level of brightness across visible; ultraviolet and infrared lighting spectrum's. 

How LEDs Work

The main part of an LED is a semiconductor chip. This chip will have two material components:

1. P-type material (Positive): This material is doped (impurities added) to create an excess of holes which are small vacancies where electrons should be.
2. N-type material (Negative): This material is doped to create an excess of free electrons.

When voltage is passed through an LED, the free electrons from the N-type material to the P-type material.  The holes from the P-type material then move toward the N-type material. They meet at a junction between the two layers and when an electron comes across a hole it falls into a lower energy level and releases this excess energy as light.

The light emitted will have a colour determined by the semiconductor material used in the diode.  Gallium Arsenide Phosphide for example produces red light and Indium Gallium Nitride produces blue light. 

White light is usually created in two ways via LED:

1. A blue LED chip is coated with a yellow phosphor material and the blue light from this excites the phosphor and this emits a yellow light. The blue and yellow light combine to give a white light.
2. A combination of RGB lights that work together to produce white light via additive color mixing.

Key Advantages of LED Lighting

• Energy Efficiency: LEDs use a much smaller amount of power than incandescent or halogen bulbs.  This can be up to 90% less power.   This leads to lower electricity bills and reduced carbon emissions.
• Longevity: LEDs have a much longer lifespan on average, often rated to last for up to 50,000 hours or more. This also contributes to lower costs for the long term and is more environmentally friendly as they do not need to be replaced as often.
• Durability: LEDs are more resistant to breakages and temperature fluctuations as they solid state devices generally made from polycarbonate rather than glass.
• Minimal Heat Emission: LEDs emit light directly leaving very little energy wasted as heat.  A heat sink is used to dissipate heat produced by the light preventing the surface from overheating.

Do LED lights fit in normal sockets?

Yes, what you need to look for is what type of base your light is.  This is a standard across all lighting technology meaning that as long as it is the same cap/base it will fit into the socket (such as bayonet or edison screw type bases).  You may find that some LED lights will be labelled as “retrofit”.  This is to offer reassurance that they will fit as replacements for previous halogen or incandescent light fittings.

Do you need an electrician to install LED lights?

If you are replacing a standard LED bulb within the home you should not need an electrician.  Replacing your previous halogen or incandescent bulb with a LED one should be as simple as replacing it as you have done in the past.  

However, there are some examples where it may be necessary to consult an electrician:

• New Lighting Fixture Installations: If you are installing a completely new light fixture where there was not one before you will need to consult an electrician.
• Hard-Wired LED Systems: Some commercial grade lights wire directly into the mains and do not use a plug or go into a standard socket.  For this it is highly recommended to consult an electrician.
• Drivers and Power Supplies: Some LED systems will require the installation of external LED drivers (power supplies) for lights that operate on a different voltage to mains voltage.  These need to be wired directly to the mains which would require an electrician.
• Dimmer Compatibility Issues: If you are looking to dim your LED light it will need to have a compatible dimmer switch and possibly a compatible dimmable driver.  Both of these would require an electrician to set them up.

Do you need special wiring for LED lights?

For standard LED bulbs you will not need specialised wiring.  LED bulbs are designed to operate on the same residential current (240V for the UK) that powers incandescent or halogen bulbs. 

For certain specialized lighting applications, the wiring requirements for the LED lights may differ:

• Low-Voltage Systems: LED strip lighting for example will often run on 12V or 24V DC. Because of this these systems will need a driver to step down the standard to convert the voltage from mains to 12V or 24V.
• Integrated LED Fixtures: Fixtures with built-in LED arrays might require specific wiring to a specific driver, this wiring will often be set in the making of the unit and will not generally need anything to be done outside of installing the fixture itself.

In conclusion - LED fixtures are a cost effective and eco-friendly development in lighting technology.  Standard LED bulbs are designed to easily replace previous incandescent or halogen lights.  You may need to consult an electrician for installation however if your LED light is not made to operate on 240V or if you have connecting control gear that may need to be replaced such as a driver or a dimmer switch.