Light sockets are used to provide electricity to common incandescent light bulbs. In areas where a higher wattage bulb is not capable of providing enough light, you do not need to install a lamp or additional light fixture. You can use your existing light socket to create two lights. This requires the use of a device known as a "Y-splitter" or a "twin-socket adaptor." It allows you to power two light bulbs with one light socket.
Remove any bulbs from the light socket.
Install a Y-splitter or "twin socket adaptor." Twist the splitter into the light socket as you would a bulb.
Insert two bulbs into the sockets of the Y-splitter. Make sure the bulbs meet the voltage and wattage requirements of the Y-splitter manufacturer. This information is typically stamped on the splitter itself or listed on the packaging.
Turn on the light to test illumination.
As of 2010, the cost of a Y-splitter averaged £1.90 to £2. You may be able to buy the splitters cheaper if you purchase more than one at a time. Lower watt and voltage bulbs typically use less electricity and cost less, but they produce less light and are not as efficient. A 150-watt bulb's filament is designed to withstand hotter temperatures, which can result in greater efficiency and light output. You would need more than two 75-watt bulbs and more electricity to equal the light output of the 150-watt bulb.
A Y-splitter may not work if you have a globe that goes over a light bulb. The increased space from two bulbs may be too big for the globe to fit over them.