Energy distribution of sunlight

Figure 2. Spectral energy distribution of sunlight at the earth s surface for solar angles of 10°, 40°, and 90°, from direct sun (--) or reflection from open sky (--) (5 ). ...

Figure 6-3 Spectral Energy Distribution of Sunlight (S), CIE IUuminant (A), Cool White Fluorescent Lamp (B), and Sodium Light (N)...

These are useful in so far as they reproduce to a fair approximation the spectral energy distribution of sunlight and provide a control of temperature and humidity. From among the several instruments that are commercially available, some of the most extensively used are briefly described here. 

The spectral energy distribution of sunlight does not depend on the orientation of a detector, whereas the spectral energy distribution of skylight and daylight depends on the plane in which the measurements are made. 

The relative spectral energy distribution of sunlight outside the earth s atmosphere is shown in Figure 10.119. 

The relative spectral energy distributions of sunlight, skylight and daylight as a function of solar altitude are shown in Figures 10.120,10.121 and 10.122, respectively. 

Figure 5-3. Spectral energy distribution of sunlight and fluorescent lamp. (Courtesy of Q-Panel Lab Products.)...

A water-cooled xenon-arc-type light source is one of the most popular indoor exposure tests since it exhibits a spectral energy distribution of sunlight at the... 

The question is, in the presence of a UV absorber, how much li ht is left to be absorbed by the photosensitizer in a pol5mier The calculations of the protective efficiency of UV absorbers for a polymeric system can be made by means of the spectral energy distribution of sunlight and the absorption spectra of the absorbers and the pol3mier. 

Hirt RC, Schmitt RG, Searle ND, Sullivan AP. Ultraviolet spectral energy distribution of natural sunlight and accelerated test light sources. J Opt Soc Am 1960 50(7) 706-713. 

Pig. 10. Energy distribution of various artificial ultraviolet sources, (a) Sunlight, (b) xenon arc, (c) carbon arc, (d) mercury lamp, (e) fluorescent lamp [reproduced with permission from Ref. 15],... 

When we are trying to reduce heat we normally care about sunlight Figure 24.1 shows two curves that describe the intensity of light coming from the sun as a function of wavelength. The top curve is the energy distribution of an ideal black-body with temperature of 5800 K, and is based on Eq. (24.1). 

Fig. 10.122. Relative spectral energy distribution of daylight (sunlight plus skylight) on a 15-0° plane for a clear atmosphere for solar altitudes of70,40,20 and 10° [2293].

Fig. 10.136. Spectral energy distribution of (—) 6500 W xenon arc lamp employed in Atlas Weatherometers and (—) noon summer sunlight at Chicago, Illinois, USA.

Figure 6.2. Energy distribution of the sunlight spectrum. A. Monochromatic mercury lamp at 254 nm. B. Black light lamp. (From Crosby, 1972.) American Chemical Society. Reprinted with permission.

Hirt, R. H. Ultraviolet spectral energy distributions of natural sunlight and accelerated light sources. National Meeting of the Optical Society of America, Detroit, Mich. (Oct. 9, 1 ). 

The efficiency in this section is defined at 25°C under 1000 W/m2 of sunlight intensity with the standard global air mass 1.5 spectral distribution. Thus, 15 percent module efficiency refers to peak watt efficiency (Wp) and implies that 15 percent of the incident sunlight energy is converted to electricity. 

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