ALTERNATIVE TO HALOGEN DOWNLIGHTS

ALTERNATIVE TO HALOGEN DOWNLIGHTS

Reporter: Jonathan Holmes (ABC TV)

Date: 29/06/2007

NOTE ON HALOGEN DOWNLIGHTS from reporter Jonathan Holmes

As the program makes clear, "low voltage" halogen lights are not low energy consumers. The standard halogen downlight uses 50 watts. The transformer in the ceiling uses a further 10-12 watts. The more modern electronic transformers use less - perhaps 3-4 watts - but that's still extra power consumption on top of the 50W bulb. So every downlight (and many people have eight or ten in a room) is using the same amount of energy as a 60 watt incandescent globe. Ten or 20 years ago the same space would probably have been lit by a couple of 60 watts bulbs, or a fluoro strip using a fraction of the energy.

The other major problem with any downlights, and halogens in particular, is the effect they have on insulation. It's illegal to lay batts over the top of any downlight, so there will be a gap in the insulation wherever one is installed. This reduces the effectiveness of ceiling insulation quite dramatically. Because halogens (unlike UCFLs and LEDs, see below) give off so much heat, they are more dangerous - although most insulation is fire-resistant or inflammable, there have been housefires caused by insulation catching fire from halogens. Indeed, the Melbourne Fire Brigade recently stated that there had been an average of 30 house fires each year in Melbourne caused by halogens. It's very important to leave at least 150mm of space between a halogen downlight and any insulation material. You can buy special protectors to put around the downlight in the ceiling. Insulation can be packed right up to the protector. But they're not cheap (around $15 each).

There are viable alternatives for anyone buying a new house or renovating an old one. Ultra Compact Fluorescent downlights cost about $25 (and the cost is going down) and run on mains power, not 12 volt. They use 9 or 11 watts and technically give almost as much light as a 50 watt halogen.

However, there are drawbacks:

1. Their light is more diffuse and less directional. In practice, therefore, you would usually need a few more UCFLs to do the same job as halogen downlights, particularly in spaces (kitchens, workrooms) where high intensity light is needed. They'd still be much more economical to run.

2. UCFLs don't work on dimmers. You can buy UCFLs which can be progressively switched from 100 per cent to 75 per cent to 50 per cent to 25 per cent brightness by successive switching on and off - a bit clunky but it does the same job as a dimmer. These are a bit more expensive than the standard UCFL.

3. They come in cold white and warm white, but some people find the light they give less attractive than the halogens.

4. They take a while - as much as a minute or two - to attain their full brightness when first switched on from cold. So people tend to switch them on and leave them on all evening, rather than switching them off when they leave a room temporarily. Because they only use a sixth of the power, or less, of halogens this doesn't much matter, but it is a disadvantage. (Mind you lots of people leave their halogens on all evening too, gobbling power.)

These disadvantages are more severe when it comes to replacing halogens with UCFLs in an existing ceiling. Mostly the UCFL bulbs will fit in the halogen fittings; if not, the UCFL fittings should certainly fit in the holes made for the halogens. But they won't give the same light effect if replaced one-for-one. If the halogens are on dimmer switches, the dimmers have to be replaced with straight on-off switches. And the 12 volt wiring and transformer have to be replaced with 240 volt wiring, so an electrician is essential and in inaccessible ceilings it can be a fiddly job. All this makes retrofitting UCFLs a pretty expensive exercise. If you have 50 halogen downlights in your home (and many people have more) you're looking at a minimum of $1500 to replace them with UCFLs – plus the cost of an electrician.

The other alternative is the LED (low intensity diode) downlight. They are VERY efficient (3-4 watts) and VERY expensive (more than $100 per unit). They are dimmable and they operate on 12 volts, so wiring and switches don't need to be replaced. They fit in the same holes as the halogens. However many LEDs operate only on special transformers so the old ones would have to be replaced.

The main snag with LEDs, apart from up-front cost, is that they simply aren't as powerful, yet, as halogens. They are fine where a low level of light is required, especially if they're going to be used for long periods (outside garden paths, corridors, hallways) but are not yet suitable for work areas and kitchens. In some cases people put LEDs around the edge of a room and keep brighter lights in the areas where they need more light.

The experts say LEDs are coming along in leaps and bounds. Within a very few years they may be a really good replacement option. Right now, they're not quite there.

The best thing to do now if you have halogen downlights already is to replace the standard 50 watt bulbs with infra-red coated (IRC) bulbs as and when the old ones blow. They are a bit more expensive but use significantly less power. There are 35W IRCs which give the same light as a 50W standard halogen and 20W IRCs which are fine for most areas where intense light isn't required. In all likelihood, as the government's ban on inefficient incandescent bulbs comes into force, the standard halogens will be mandated off the market anyway.

Apart from that, just remember that if you've already replaced your standard incandescent globes with compact fluorescents, your halogens will using around six times as much power, per light, as any other light in the house - so if you're not in the room, turn them off.

And if you're building or renovating, don't let builders, designers, architects or electricians (many of whom know little and care less about energy efficiency) talk you into installing halogens. Ideally, avoid downlights that involve piercing the ceiling altogether, so that you can insulate the ceiling completely.