The problem with halogen downlights
Submitted by: Margaret McKenzie, Thursday, February 2, 2012
While halogen downlight installations have considerable aesthetic appeal they are generally very energy inefficient when compared with other lighting solutions. This is because most downlight installations use more lights than other lighting solutions. In addition most installations use 50 Watt lights.
The increase in electricity price in the last few years has meant that downlight installations are starting to cost their owners a considerable amount of money. For instance a house with 40 downlights of 50 Watts each could use up to 3,650 kWh per annum to power the lights. This is calculated as follows:
40 lights * 50 Watts * 5 hours of use per night * 365 days per year = 40 * 0.050 kWh * 5 * 365 = 3,650 kWh
In the city of Durban electricity is currently charged at R1,07 per kWh including VAT. So 40 downlights will cost up to R3905.50 a year in electricity in a home in Durban.
In addition to be inefficient halogen downlights are a potential fire hazard because they operate at 250°C. This is compounded by the fact that many halogen downlight installations require transformers that also generate heat. Transformers are used because most downlight installations use 12 volt lights. As electricity supply in South Africa is in the 220 to 240 Volt range transformers are required to convert electricity to 12 Volts for the lights. Transformers also use a few Watts each to operate contributing to the overall energy use of a downlight installation.
There are now a number of alternatives to halogen downlights on the market. These alternatives will be discussed in a later post. In addition have a look at our article on lighting considerations to help with selecting an energy efficient replacement for all your lighting needs.
You may also be interested in:
- Selecting alternatives to halogen downlights
- Lighting considerations before changing to energy efficient alternatives
- Learnings from recent solar PV installations in South Africa
- Total’s affordable solar lights empower communities
- An introduction to solar PV rooftop installations
- New guide promotes energy efficient public lighting
- Key considerations for green roof installations in South Africa
- Eskom launches lighting design competition