Page 110 - Design of Solar Thermal Power Plants

98 2. THE SOLAR RESOURCE AND METEOROLOGICAL PARAMETERS

FIGURE 2.12 RSP-3G irradiance meter.

TABLE 2.16 Parameter Indices of CMP21 Pyranometer in the Kipp & Zonen System
Item Index
Spectral coverage 285e2800 nm
2
Sensitivity 7e14 mV/(W m )
Response time 5s
2
Directional error (80 degrees, 1000 W m ) <10W m 2

Sensitivity upon temperature ( 20 Cto þ50 C) 1%

Suitable temperature range 40 Cto þ80 C
Maximum solar irradiance 4000 W m 2
Field of view 180 C

is available for adjustment; normally, as for the perennial observation, it
can be adjusted to 10 min per time.
The main configuration of a reference irradiation station is shown in
Table 2.17. Fig. 2.13 indicates the mean DNI on a 10-min basis measured at
Badaling during the period from 10:00 a.m. on November 29, 2011, to 9:30
a.m. on January 5, 2012. According to the figure, during December
Badaling had plenty of clear days.
Figs. 2.14 and 2.15 separately display the relationships between DNI
and global irradiance on the horizontal surface, as well as DNI and diffuse
irradiance on the horizontal surface. According to Fig. 2.14, during a clear
day the global irradiance on the horizontal surface is less than the DNI