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2. Fluorescent-lamp formats - Wikipedia

   en.wikipedia.org/wiki/Fluorescent-lamp_formats

   In the 1970s, 34-watt energy-saving F40T12 fluorescent lamps were intoroduced in the United States. In the 1980s, T8 32-watt lamps were introduced, [ 8 ] but unlike the T8 tubes introduced in Europe, these T8s are not retrofits and require new matching ballasts to drive them.

3. Fluorescent lamp - Wikipedia

   en.wikipedia.org/wiki/Fluorescent_lamp

   The efficacy of fluorescent tubes ranges from about 16 lumens per watt for a 4 watt tube with an ordinary ballast to over 100 lumens per watt [51] with a modern electronic ballast, commonly averaging 50 to 67 lm/W overall. [52] Ballast loss can be about 25% of the lamp power with magnetic ballasts, and around 10% with electronic ballasts.

4. Compact fluorescent lamp - Wikipedia

   en.wikipedia.org/wiki/Compact_fluorescent_lamp

   The luminous efficacy of a typical CFL is 50–70 lumens per watt (lm/W) and that of a typical incandescent lamp is 10–17 lm/W. [38] Compared to a theoretical 100%-efficient lamp ( 680 lm/W ), CFL lamps have lighting efficiency ranges of 7–10%, [ 39 ] versus 1.5–2.5% [ 40 ] for incandescents.

5. United States lighting energy policy - Wikipedia

   en.wikipedia.org/wiki/United_States_lighting...

   The 2009 IECC, chapter 2 defines high efficacy lamps as compact fluorescent lamps, T-8 or smaller diameter linear fluorescent lamps, or lamps with a minimum efficacy of: [21] 60 lumens per watt for lamps > 40 watts, 50 lumens per watt for lamps > 15 watts and ≤ 40 watts, and; 40 lumens per watt for lamps < 15 watts

6. Luminous efficacy - Wikipedia

   en.wikipedia.org/wiki/Luminous_efficacy

   Luminous energy per unit time Luminous intensity: I v: candela (= lumen per steradian) cd (= lm/sr) J: Luminous flux per unit solid angle: Luminance: L v: candela per square metre: cd/m 2 (= lm/(sr⋅m 2)) L −2 ⋅J: Luminous flux per unit solid angle per unit projected source area. The candela per square metre is sometimes called the nit ...

7. LED lamp - Wikipedia

   en.wikipedia.org/wiki/LED_lamp

   A 230-volt LED filament lamp, with an E27 base. The filaments are visible as the eight yellow vertical lines. An assortment of LED lamps commercially available in 2010: floodlight fixtures (left), reading light (center), household lamps (center right and bottom), and low-power accent light (right) applications An 80W Chips on board (COB) LED module from an industrial light luminaire, thermally ...