Ed has made inert gas lamps in the past in order to try to eliminate the use of mercury. He replace the mercury in the bulbs with inert gases to create the correct color combination. The best lamp he could come up with in doing so created only 20-30 lumens per watt. This was better than the average incandescent light bulb, but therefore also had less than half the efficiency of a fluorescent lamp.
His next attempt was to remove the phosphor from the lamps and leave the mercury, thus using the light from low vapor pressure mercury. This caused the lamps to go from 75 lumens per watt to 7 lumens per watt, clearly not a solution. That is even less than an incandescent bulb’s lumens per watt.
Currently there are laws evolving around the use of incandescent light bulbs in the future. They are moving towards the regulation that bulbs used in the future need to be 30 lumens per watt or better. Currently incandescents do not fit this standard and a new type of incandescent bulb will need to be developed if they want to survive. The present initiative is for incandescent light bulbs to be phased out by 2012 in the US, and possibly 2010 in Europe.
LEDs vs. CFLs. LEDs have been suggested as a replacement to CFLs, since CFLs use mercury. LED lamps are NOT as efficient as CFLs. They do not work well as a general light source to replace incandescent bulbs like CFLs. LEDs do not have the same amount of lumens per watt. There are also heat issues with LEDs as they tend to get extremely hot. CFLs on the other hand remain cooler than even incandescent bulbs. LEDs are better for specific purposes, such as their current uses in flashlights or traffic lights. The light given off from LEDs does not make them suitable for reading light like fluorescent lighting that creates the full spectrum.
There are so many types of lighting to choose from today it can be difficult. There are incandescent light bulbs, CFLs, LED, HID. It seems that each type of light is better for different applications. The fluorescent lighting market is much more broad. Others have a more specific ‘best application’ such as LED lights for traffic lights or flashlights and HID lights for stadium lighting.