LOW-COST SOLAR COOKERS
To Boost Rural Entrepreneurship
Inclined Box-Type Solar Cooker
The key feature of the designed new box-type cooker (Picture 1) is that, it is designed to tilt towards the sun so that direct radiation is perpendicularly accessible to increase solar irradiance on the cooker face. Two foldable mirror reflectors are conveniently attached at both longer sides of the cooker at an angle of 115° with cooker face to boost up the energy collection. The new cooker allows the user to cook more meals as the cooker still works when the sun is somewhat low in the sky. The cooker is provided with four cooking pots.
Merits/Advantages
This solar cooker is able to access solar radiation from perpendicular direction from 9 a.m. to 3 p.m.
Two foldable mirror reflectors are conveniently attached at both longer sides of the cooker to boost up the energy collection.
The new cooker allows the user to cook more meals as the cooker still works when the sun is somewhat low in the sky.
Material required for fabrication
Light duty bending machine, potable drilling machine, grinding machine, shear cutting machine, hand shear, rubber and wooden mallets, hammer, pliers, screwdriver set, wrench set, measuring tape, steel scale, calipers, marking gauge work table with bench vice and some gigs and fixtures for convenient working.
Project economics
Minimum economic unit is 30 cookers per month.
Total investment is Rs 250,000 working capital for two months.
At an estimated cost of Rs3,000 per cooker one can earn a profit of Rs10,000 per month.
Low-Cost Wooden Box Solar Cooker
The low-cost wooden box solar cooker (Picture 2) is very appropriate for rural applications for its simplicity and low cost. Fabrication of the cooker is very easy and so, the cooker can be built by semi-skilled village artisans by using simple hand tools and with locally available raw materials. The fabrication cost is only Rs 1,000.
Test results
(reorientation is done after every 30-minute interval)
Intensity of solar radiation: 0.6 kW per m2.
Peak temperature of empty cooking pot lid: 130°C.
Cooking performance: Time taken for cooking 250 g of rice is 2 hours 15 minutes.
Material required for fabrication
Wooden plank, G I Sheet, aluminium foil, plain window glass, mirror glass, dull black paint, gasket material and adhesive, hinge, stay links, handle, seat, clips, screws, etc.
Article courtesy : Shri Sankha Subhra Datta is a Senior Section Engineer (Mechanical) in the Diesel Locomotive Shed, NF Railway, Siliguri Junction, West Bengal, India. E-mail: subhradatta611@gmail.com.