This ppt is for only overview of topic

1. Principle of measurement of
solar radiation
(1)Principle of Thermocouple
(2)Photovoltaic principle
(3)Principle of solar concentration

2. PYRANOMETER
• Measure beam radiation + diffused radiation
• Measure diffused radiation when shading ring is used
PRINCIPLE
 Black surface absorb
 White surface reflect
unnecessary heat
 Temp. Diff. of B and W detect
thermopile in mV
 Calibration

3. PYRANOMETER
CONSTRUCTION
 Thermopile with black & white coating
 Absorb solar radiation of spectrum 300-50000 nm
wave length
 Glass dome control spectral response of 300-2800
nm while 180 ͦfield view
 Glass dome prevent leakage of heat radiation from
sensor
 O/P in mV calibrated in Watt per square meter

4. PYREHELIOMETER
• Used to measure direct beam radiation
Principle:
Temperature difference between black and
white
↓
Converted into EMF
↓
proportional to energy incident on surface

5. Construction and Working:
 Shape collimator tube
 Thermopile junction at black side of
sensor plate
 Cone angle at 50 degree
 Solar sensor produce o/p in mV
PYREHELIOMETER

6. SUNSHINE RECORDER

7. SUNSHINE RECORDER
• Use to measure duration of the day when there was bright sun
shine give beam radiation
CONSTRUCTION
 Transparent glass sphere mounted on heavy base
 Bowl provided below glass sphere
 Grove is provided to insert paper
WORKING
 Glass concentrate solar radiation
 Paper receive solar radiation on it which is chemically
treated
 Paper give burn mark
 When the sun shine is present

8. PHOTOVOLTAIC SOLARIMETER
• Typical pyranometer measure solar flux intensity
• Working principle PV cell
• Solar energy  Solar cell  Variable resistive load
Current produced
• Moved in direction off sun
• Meter calibrated in
watt per meter square