Downlights - why our CFL downlights beat halogens!

We wanted the unobtrusive look of downlights in our new house, without the environmental cost.  Typical halogen downlights are very popular in the average new home, but even when you use the newer 35 watt extra bright halogens, they are still worse than the ordinary incandescent globe (now banned) when you consider that usually two or four downlights are used in the place of a single incandescent globe.

 

Adding to high energy consumption, halogen downlights have two negative effects on passive solar design:

·      High heat created by wasted energy not converted into light adds unwanted heat in summer

·      Large “holes” are required to be left in the insulation around each downlight fixture to minimise the fire hazard

 

The newer more efficient halogen globes consume 35 watts instead of 50 watts, helping to reduce consumption & heat for existing fixtures, and there are now also transformers available (converting 240v mains voltage to low 12v voltage) using only 6 Watts of energy per circuit, instead of around 20 Watts.

 

The following table compares the more efficient halogen downlights with our compact fluorescent (CFL) downlights:

 

 

Voltage

Energy Consumption

Transformer

Cost

Light Output

“low energy” Halogen Downlight

12v

35w

6w

Same

Same

CFL Downlight

240v

15w

none

 

COST: Our CFL downlights cost only $13.95 each, including the globe, and were installed for the same price as a halogen downlight.  Unlike CFL globes of the past which have a definite “colour” to the light, the newer globes are brighter and closer to neutral.  We chose Warm White spiral globes which give good downward light.

 

To make sure we are only using the energy we need to, we have separate circuits for switching the lights.  This gives us the added ability of creating different lighting effects for our multi-function living space.

 

While nearly all of the lights are CFL, we have bought a few experimental LED globes which use the same fixtures.  LED technology is even more efficient at converting electricity to light without wasting it on heat, and can produce attractive bright white light.  However the globes are expensive, though very long lived at 10 to 15 years, except for several of ours which failed within the first few months.  We have the option of replacing expired CFL globes with equivalent LEDs in the future.