Thomas Alva Edison revolutionised lighting with the development of the first commercially successful incandescent light bulb well over a century ago.
Yet, this 1879 technology is still used in houses, apartments and offices all over the world, practically unchanged since he first dreamed it up.
Never mind that the bulbs are enormously inefficient, and less than 6% of the energy they use is converted into useful light.
About 15% of household energy goes towards running light globes, of which the incandescent and halogen varieties are by far the biggest energy guzzlers, especially in new (and increasingly larger) homes.
In 2007, former Federal Environment Minister Malcolm Turnbull announced a plan to phase out incandescent bulbs starting in 2009—a world first by a national government—in a bid to prevent up to 800,000 tonnes of greenhouse gas from wafting into our atmosphere.
As green retailers love telling us, spending $100 on light globes can reduce your household's greenhouse gas by about 12 per cent.
Number Crunch
| Type | Watts | Energy/day | Energy/year | Cost/year | CO2/year |
| Halogen | 50 | 0.3 kWh | 109.5 kWh | $14.02 | 115 kg |
| CFL | 11 | 0.066 kWh | 24.1 kWh | $3.08 | 25 kg |
| LED | 6 | 0.036 kWh | 13.1 kWh | $1.68 | 14 kg |
| Incandescent | 75 | 0.45 kWh | 164.3 kWh | $21.02 | 173 kg |
