3. Solar energy availability on earth
 The surface receives about 34% of the total solar energy that
solar energy that reaches the earth.
 According to World Meteorological Organization earth surface
receives 120 Watts per sq. meter direct radiance.
4. Need of solar dryer
• Cost effective
• In rainy season and winters due to presence of moisture a foul smell develops
in food grains and there is full possibility of development of pests.
• It make us not to spreading food grains which was required earlier at regular
period of time.
• Drying in the direct sun has the risk of damaging the complete harvest by
rainfall.
• Dehydration of fruits, potatoes, onions and other vegetables
13. Benefits of solar dryer
• Much less time is required for drying as compared to direct drying
because of black body.
• Protection of the drying products from insects but also from birds, dogs,
especially for drying meat and fish.
• The products is hygienic because microorganisms, insects and flies are
killed.
• Protection from rain.
• Protection from pollution by dust etc.
• Protection from the wind which can blow away the food.
14. Drawbacks of solar dryer
• Limited time
• Quality of products are not obtained in some cases.
• High initial cost
• Skilled person required
15. Application of solar dryer
Agricultural
crop drying
Food
processing
industries
Fish and
meat
drying
Dairy
industries
Textile
industries