After the geyser, space heating is next biggest energy drain in most homes (around 16% of your electricity bill). Think in terms of warming yourself and the immediate area you're using, rather than the whole house.
Warm up with extra clothing first before resorting to heaters. Remember your extremities: prevent heat loss with slippers, thick socks, gloves, scarves and beanies. Keep cosy blankets or throws available in the living room and study too, not only the bedroom.
If you do resort to heaters, use them to warm the area you're using, not the whole house: close the door of the room you're in , and sit near the heat source. A two-kilowatt fan heater, or small bar or gas heater, is fine for heating one room.
- Olivia Rose-Innes, EnviroHealth Editor, Health24, July 2012