After years of work, Moore was able to extend the operating life of the lamps by inventing an electromagnetically controlled valve that maintained a constant gas pressure within the tube. Although Moore’s lamp was complicated, was expensive to install, and required very high voltages, it was considerably more efficient than incandescent lamps, and it produced a closer approximation to natural daylight than contemporary incandescent lamps. From 1904 onwards Moore’s lighting system was installed in a number of stores and offices. Its success contributed to ’s motivation to improve the incandescent lamp, especially its filament. GE’s efforts came to fruition with the invention of a -based filament. The extended lifespan and improved efficacy of incandescent bulbs negated one of the key advantages of Moore’s lamp, but GE purchased the relevant patents in 1912. These patents and the inventive efforts that supported them were to be of considerable value when the firm took up fluorescent lighting more than two decades later.
Although Edison lost interest in fluorescent lighting, one of his former employees was able to create a gas-based lamp that achieved a measure of commercial success. In 1895 demonstrated lamps 2 to 3 meters (6.6 to 9.8 ft) in length that used or to emit white or pink light, respectively. As with future fluorescent lamps, they were considerably more complicated than an incandescent bulb.
Although there are a large number of lighting options, the majority of lighting in homes is done by either or fluorescent lights. Fluorescent lighting has a considerable advantage in energy efficiency over incandescent lighting. Fluorescent lights can produce 50-100 /watt compared to about 15 lumens/watt for incandescent bulbs.