Halogen lamps smoke when switched on

Which advantages and disadvantages the halogen lamp really has

Since September 1, 2012, classic light bulbs can no longer be manufactured and sold. The reason for this: They only convert around five percent of the electricity into light and therefore only achieve energy class D, which is hardly efficient. What about the halogen lamp?

The EU Parliament planned a ban on energy efficiency class C lamps six years ago, which should actually come into force in September 2016. Most of the halogen lamps would also be affected, as the majority of them belong to energy efficiency class C lamps. Last year, however, the deadline was postponed by another two years.

Some older halogen lamp models have already been banned in the course of the EU regulation and are no longer sold. Reason enough for eLIFE to illuminate the halogen lamp more precisely:

eLIFE sheds light on why halogen lamps are not energy efficient compared to LEDs

Why the halogen lamp is still so popular

Halogen lights provide natural, almost daylight-like lighting. Their light is generally whiter than that of compact fluorescent lamps, commonly known as energy-saving lamps, or the light of LEDs. That is why they are often used in areas that need to be well lit. In addition to the natural color of the halogen light, the service life has also been one of the advantages of the halogen lamp. Because although the glass of the energy-saving halogen lamp heats up to around 250 degrees Celsius each time it is lit, the halogen lamp lasts up to 3,000 hours, which is roughly three times the life of a light bulb.

However, they are clearly inferior to energy-saving lamps with a service life of around 10,000 hours and LEDs with as much as 25,000 hours. And when it comes to energy consumption, halogen lamps are far behind. Although they are 30 percent more efficient than the old lightbulbs, they use almost three times as much energy as high-quality energy-saving lamps and LEDs.

Halogen lamps became the focus of consumers, especially immediately after the ban on lightbulbs. Back then, around five years ago, LEDs and compact fluorescent lamps were not as developed as they are today. LEDs were expensive and did not provide the same bright and above all fast light output as halogen lamps. That has changed, however, modern LEDs are also available in strong warm-white light quality at an affordable price - and they are also more durable and energy-efficient.

How the halogen lamp works

In principle, the halogen lamp works just like a normal light bulb, only as a "tuned" variant. In both types, a tungsten filament heats up to incandescent through the flow of current and thus generates light. The specialty of the halogen lamp is its small quartz bulb, which gives off very little heat to the environment. This allows the halogen lamp to be heated a few hundred degrees higher than a light bulb, which considerably increases the efficiency, i.e. the brightness.

With the higher temperature, the halogen lamp would actually have a shorter service life - but this is prevented by a trick: the halogen gas mentioned is located in the glass bulb. Put simply, this gas ensures that the thin filament is not used up so quickly. Therefore it shines brighter and has a longer lifespan than the classic light bulb.

The inside of the halogen lamp is heated by the current flow and thus generates light.

The color of daylight

Like the old light bulbs, halogen lamps are so-called temperature radiators. During the process of lighting, infrared heat radiation is generated. Most people perceive the color of such light as pleasant and warm, which is why halogen light is also referred to as warm-white light. We perceive this light as natural, because daylight, generated by the sun, has a similar light spectrum and all colors in halogen lighting are very similar to the color impression in daylight.

The energy consumption of halogen lamps

Despite all the listed disadvantages compared to LEDs and energy-saving lamps, the halogen lamp currently still has some advantages, which mainly relate to the way in which it is used and the light. Due to the further technical development of the more energy-efficient LEDs and energy-saving lamps, however, these will no longer be unique selling points in the near future.

The three advantages of halogen lights

  • Halogen lamps are bright as soon as they are switched on. Their light is neutral, which is why it harmonizes well with colors.
  • Halogen lamps can be used universally - thanks to their compact design, they can also be used where there is little space.
  • Halogen lamps emit a natural, intense light that is similar to pleasant daylight.

Halogen lamps are immediately bright, provide natural light and can be used universally.

The three disadvantages of halogen lights

  • Halogen lamps require almost three times as much energy as energy-saving lamps and almost four times as much as modern LEDs.
  • With a service life of 3,000 hours, they are far inferior to energy-saving lamps (up to 10,000) and LEDs (up to 25,000).
  • They get very hot and must therefore not be used near flammable materials.

Halogen lamps require almost four times as much energy as modern LEDs.

Where halogen is used

Halogen lamps are available as low-voltage lamps with 12 volts or 24 volts and as high-voltage lamps that are operated with a mains voltage of 230 volts. They are available in all-round, point-like and linear designs as well as reflector lamps for generating directed light. Due to the good color rendering and the pleasant light color for living areas, halogen lamps have been used in many areas to this day. However, modern LEDs meanwhile already have the same positive properties and also better energy efficiency.

Halogen lamps are available in many different versions - here is an overview of common models from Osram.

Nevertheless, the halogen lights are still very popular and are particularly popular in those areas where they can show their full potential: for example around cooking and eating or above the bathroom mirror. They are also still used in corridors, as they immediately provide full light output when switched on. If someone is in the hallway and needs the light, the poor energy efficiency and comparatively short lifespan are of little consequence. However, as large-area and dimmable basic lighting, the power guzzlers really should be avoided.

Good lighting mood: combination of many lights

Lighting design is particularly efficient thanks to various lighting systems. Less bright or indirect light creates a nice atmosphere in large living spaces. These can be illuminated by energy-saving LEDs, which are already available in different light colors from warm to cold. Halogen lamps could be used where bright light is needed, for example because an activity such as cooking or facial care is in the foreground. The use of halogen light also makes sense to draw attention to steps and edges.

Note on dimming the halogen lamps

Dimming the halogen lamp is not recommended! Because dimming reduces the temperature and pressure in the halogen lamp, which in turn results in a shorter shelf life. The lamps emit less and less light due to the permanent dark mode and eventually break. A particular disadvantage: halogen lamps can only be dimmed if a special transformer is used. If it is not completely disconnected from the mains, it always draws stand-by power!

The eLIFE conclusion:Even if the halogen lamps are still used, due to their high energy consumption they should only be used where they can really make full use of their advantages, such as bright, pleasant and fast light. They are not a real alternative in the long run. Compact fluorescent lamps and LED lights, which are vastly superior to halogen lamps in terms of energy efficiency and service life, are better suited as basic lighting.