If you currently have low voltage halogen downlights, each using 50+ watts of power, a cheap, easy way to save power is to replace the lamps from a 50W, down to a 35W, or even a 20W. This of course depends on how your lighting is laid out, ie the spacing of downlights or lightfitting height etc.
Some situations, you can change down to 35W or 20W and hardly notice the difference, other situations you can't. Added bonus of less heat in the roofspace as well.
As to the replacements for old type incandescent bulbs, those new mains halogen globes mentioned by Witzl are very good, nice light etc, although they don't offer much of a saving in power over the old incandescents.
New CFL lamps are very good once you are used to them. Bonus with them is that as they don't generate as much heat, you can put a much more powerful CFL (18W/80-90W equiv.) in a lightfitting which was limited to say 60W max in the incandescent. They have come right down in price too.
For the outside, there is a 23W ES PAR38 floodlight globe available (bunnings abt $23) which is a replacement for the old, very common 120/150W ES (screw in) PAR38 floodlight. These are fantastic, I have them at my own house. A big saving if you use outside lights a lot.
As for LED, they are still too expensive to be worthwhile, at this stage. But that will change down the track. I don't trust the lifespans either (from personal experience).
Some situations, you can change down to 35W or 20W and hardly notice the difference, other situations you can't. Added bonus of less heat in the roofspace as well.
As to the replacements for old type incandescent bulbs, those new mains halogen globes mentioned by Witzl are very good, nice light etc, although they don't offer much of a saving in power over the old incandescents.
New CFL lamps are very good once you are used to them. Bonus with them is that as they don't generate as much heat, you can put a much more powerful CFL (18W/80-90W equiv.) in a lightfitting which was limited to say 60W max in the incandescent. They have come right down in price too.
For the outside, there is a 23W ES PAR38 floodlight globe available (bunnings abt $23) which is a replacement for the old, very common 120/150W ES (screw in) PAR38 floodlight. These are fantastic, I have them at my own house. A big saving if you use outside lights a lot.
As for LED, they are still too expensive to be worthwhile, at this stage. But that will change down the track. I don't trust the lifespans either (from personal experience).