SOLAR COOKERS IN INDIA
With India receiving daily solar energy in the region of 5 to 7 KWH/M2 for 300 to 330 days in a year, solar cookers introduced some years back, have proved popular inspite of reduction in subsidy rates.
Most popular in India are the box type solar cookers with a single reflecting mirror being promoted by the Ministry of Non-conventional Energy Sources since 1982. These cookers are manufactured mainly by small/tiny industries to a set of specifications developed by MNES, later approved by Bureau of Indian Standards. There is an estimated potential demand of 10 million solar cookers in this country. In India a major portion of the market is covered by box type cooker and a small portion of the market share is taken up by community type box cooker/parabolic type cooker. Manufacturers intending to manufacture and market solar cookers under the subsidy scheme have to compulsorily get the cooker tested and certified by an authorized test center. There are about 40 manufacturers whose combined annual production capacity is 75000 solar cookers.
These cookers have proved immensely popular in the rural areas where women spend a lot of time foraging for firewood.
To popularize the solar cookers in urban areas the Ministry has formulated a strategy to introduce cookers with electrical backup which consume low electrical power.
Solar cookers are available with and without electrical back in different sizes and can be procured from dealers/manufacturers/nodal agencies/Aditya solar shops all over India.
A family size solar cooker is sufficient for 4 to 5 members and saves about 3 to 4 cylinders of LPG every year. Life of this cooker is 10 to 20 years. This cooker costs around Rs. 1000 after allowing for subsidy.
Concentrating solar cookers have been developed and deployed but the quantity is low and until wider acceptance is gained or some modification is made in the concentrating solar cooker which will allow the solar rays to be directed to a hot spot inside the kitchen, people will shy away from these giant contraptions.
A community type parabolic concentrating solar cooker developed by ULOG Group of Switzerland is being promoted by an NGO in Gujarat and has met with moderate success. This cooker is designed to direct the solar heat to a secondary reflector inside the kitchen which focuses the heat to the bottom of a cooking pot. This cooker costs upward of Rs. 50000 and it is also possible to actually fry, bake and roast food. More than 50 such cookers have been deployed under a project sponsored by Sardar Patel Renewable Energy Research Institute and Gujarat Energy Development Agency.
Unique in India is the solar steam cooking system installed at Brahmakumariís Ashram at Mount Abu with financial assistance from German Government. This system consists of 24 Scheffler paraboloid reflectors, two each of which are installed to focus sunlight on a square type insulated fin and tube receiver. Twelve such receivers are focused by 24 reflectors. The concentrators track the Sun automatically using a mechanical clockwork arrangement and a DC motor run by photovoltaic power panel helps in resetting the reflectors to face the Sun as required. This system generates 500 Kgs of steam which is enough to cook two meals for 500 people. More than 1000 people can expect to receive cooked food from this system within an hour, provided sunshine is adequate.
more to come...