Halogen, HID or LED? Aside from cost, how do you decide which one.
As per part 1 and 2 the information provided here is to the best of my knowledge and experience and may contain my personal opinion.
Halogen – Sometimes referred to as Filament, Incandescent or Quartz Halogen use a filament of wire with a super high melting point that is glows brightly when current passes through it. It also gets very hot wasting most of the power consumed as heat. Halogen globes in driving lights may have you turning the switch on and off to see if they are actually working if installed on a modern vehicle. Back in the days of sealed beam headlights a good set of driving lights made the world of difference, but with modern headlight technologies, the majority of owners would be disappointed in the performance of most driving lights with standard halogen globes unless they have installed very high wattage globes, generating heaps of heat and sucking heaps of power from the vehicles electrical system. Good quality heavy duty relays and wiring are paramount for successful installation of halogen driving lights. Note if the packaging doesn’t state that the lights are LED or HID then they are a type of halogen filament globe.
HID or High Intensity Discharge uses a gas (Xenon) to carry an electrical arc between two terminals in the globe, which is essentially how a fluorescent household light works. HID provides much more light for each watt of power used compared to incandescent and also provides light with a much higher colour temperature (whiter). HID lights have the best distance reach in both spot and spread beam formats. HID lights have a warm up time on initial start up as they need to be warm to work. This has limited their application in headlight systems with manufactures inventing mechanical flaps and the like to change between high and low, however is rarely a problem when in additional driving lights. HID lights, like halogen have a removable globe, and they also have an inverter to provide high voltage to the globe. As a rule all parts are available individually for HID lights as they are for halogen.
LED is fast becoming very popular due to very white light and low power usage. LED lights have no user serviceable parts and the LEDs are expected to last the life of the light. Some can be repaired, but it isn’t a matter of changing a globe in the carport or on the side of the road. The majority of LED lights are made up of a bar or group of individual LEDs with their own little reflectors. To create a spread beam diffuser lenses are placed over them. This does not allow for controlled beam shapes to the same degree that a free form reflector does and helps explain why they don’t get the same distance in a spot beam that a HID can. Another point to note about LED lighting is that light output and life of LED decreases as heat increases. High powered LED lights get quite warm and as they only have passive cooling system, must have constant air flow. A high powered light bar in a warm and stationary environment will be duller and have a significantly shorter life than one on the front of a highway vehicle. In stationary, slow moving or rear mounted applications several lower powered work lights are a better option than one high powered unit.
OK so after three pages of information and opinion what lights do I use? Although quite large in size so not suitable for all vehicles I use a pair of Narva Ultima 225, 50 watt HID Spread beams and +120 halogen globes in my High and Low beams of the vehicle.