The familiar incandescent bulb is the most common but least efficient kind, although some types are better than others.
Low-wattage bulbs, or economy lamps, will give you the same output as regular bulbs for about 12 per cent less power.
Long-life incandescents are more expensive to buy and use, but should last more than 10000 hours - an advantage in hard-to-reach places.
For extra efficiency and longer life, try halogen mains voltage lamp bulbs. They cost about twice as much as tungsten bulbs, but give nearly twice the light - and they last roughly 3500 hours. Mains voltage bulbs also fit standard caps (bayonet and screw), unlike low-voltage halogen bulbs, which need specially designed fittings and bulky transformers.
Most efficient are fluorescent tubes. They and their fixtures are costly, but a tube lasts an average of 9000 hours and gives triple the light per watt of an incandescent lamp bulb.
For easy removal of an outdoor bulb, coat the threads with silicone spray polish before you screw it in.
