g., neon lighting) and the preference for color renderings that are similar to daylight. Incandescent lights still dominate both interior and exterior residential lighting. However, gas discharge lamps (e.g., fluorescent, metal halide, and high pressure than sodium) predominate in most other settings. Gas discharge lamps generate light by passing electric arcs through chambers containing gases Inhibitors,Modulators,Libraries which glow at specific wavelengths (emission lines) as electrons shift orbital shells. Gas discharge lamps are more efficient than incandescent light bulbs since many of their primary emissions are in the visible portion of the spectrum. Additionally, phosphors are used to shift emissions to desired wavelengths. Fluorescent lights dominate office Inhibitors,Modulators,Libraries interior lighting but are also used extensively for outdoor lighting in countries such as India.

Mercury vapor lamps, metal halide lamps and high pressure sodium lamps dominate for large area lighting, including interiors of building with high ceilings, exteriors of non-residential buildings, street and road lighting. Inhibitors,Modulators,Libraries Liquid fuel lamps (e.g., kerosene) are the primary lighting source for approximately 1.6 billion people who lack access to electricity [1,2].Phospors are mineral compounds that Inhibitors,Modulators,Libraries absorb radiation of certain wavelengths and then re-radiate at longer wavelengths for a short period. The application of phosphors in fluorescent and induction lamps allows for the conversion of ultraviolet radiation from mercury vapor arcs into visible radiation. Some Cilengitide mercury vapor and metal halide lamps are also coated with phosphors.

Some LED sources also use phosphors. A typical approach to producing ��white�� light from LEDs is to combine a blue LED (peak ~460 nm) with a phosphor coating to produce a broad spectrum in the green-yellow-red range. The manufacturer is able adjust the balance between these two components to produce a range of correlated-color temperatures Gemcitabine order (CCTs) for ��white�� LEDs.The potential for future cost savings and carbon emission reductions achievable through replacing inefficient lamps and fixtures is enormous. Worldwide lighting consumes an estimated 19% of all electric power, more than all the nuclear and hydro-power plants combined [1]. The total cost of lighting worldwide is estimated to be $460 billion per year (2005), with 75% of this cost attributed to electricity [1]. Total annual carbon emissions associated with lighting have been estimated at 1889 MtCO2 [1]. During the next several decades one can anticipate a substantial transformation in lighting types worldwide�Cwith the widespread installation of long-lived energy efficient lights, installation of shields to restrain the escape of light into the sky, and installation of controls to dim or shut off lights when no one is present.