It is a concentrating type parabolic dish solar cooker useful for homes & small establishments. A typical dish solar cooker has an aperture diameter of 1.4 meter and focal length 0.28 meter. The reflecting material used for fabrication of this cooker is anodized aluminum Sheet, which has a reflectivity of over 80%. The tracking of the cooker is manual and thus has to be adjusted in 15 to 20 minutes during cooking Time. It has a delivering power of about 0.6 KW which can boil 2 to 3 liters of water in half an hour. The temperature achieved at the bottom of the vessel could be around 350 to 400o C which is sufficient for roasting, frying and boiling. The cooker having a thermal efficiency of around 50% can meet the needs of around 15 people and can be used from one hour after sunrise to one hour before sunset on clear days. It can be easily dismantled and assembled by anybody and thus may be nicely packed and transported anywhere in the country. The cooker is user friendly as the place of vessel to be kept for cooking is at a level which is convenient for the people to use.
The cooker can save up to 10 LPG cylinders/year on full use at small establishments. The cookers with imported reflectors having a reflectivity of over 90% will have a higher cost. This should include the cost of accessories like pressure cooker, cap, hand gloves & goggles, cooker manual, packing etc.
Around 20 years for metallic structure. Reflecting sheets may however, have to be replaced once in 5 years due to degradation in reflectivity.
1 ½ to 3 years depending on the extent of use & the place of utilization (for commercial establishments and large families the pay back period is less).
Solar Cooked food preserves most of the vitamins, minerals and antioxidants. Vitamins and minerals increase the nutrition value while antioxidants protects from cancer. Boiling and steaming type food diet protects from most of the diseases as compared to frying, grilling and micro waving. Burning any fuel like cooking gas, kerosene, wood etc. releases gases like carbon-dioxide, carbon monoxide and nitrous oxide. Intake of these gases for long duration is a cause of major respiratory diseases in housewives. Continuous inhaling of higher carbon dioxide and carbon monoxide promotes cancer. Solar cooked food is easily digestible. It gradually relieves stomach disorder, constipation, gastric trouble and acidity. Solar Cooking improves the taste of the food to a very large extent.
Solar cooking does not burn any fuel and is one of the most eco-friendly options. All other fuels like wood, cooking gas etc. generate Carbon dioxide, Carbon monoxide and Nitrous oxide which are severely responsible for pollution. CO2 is a major green house gas responsible for global warming leading to natural disasters like Tsunami, Cyclone, Volcanic eruption etc. In rural areas saving firewood means saving trees. One family consumes 3 trees in the form of firewood in a year. If solar cookers are used then trees per solar cooker per year can be saved. Solar cooking can help in preserving the fast diminishing forests.
One can save up to one cooking gas per month by proper utilization of solar cooker and then recover the cost within a year. Even moderate users recover the cost of the solar cooker within 2 years. With current rise in LPG cost and subsequent rise every month the saving potential is enormous.
India imports more than 75% of the oil, it consumes. With crude oil prices in the world rocketing past $ 54 per barrel, solar cooking will help save in kerosene & cooking gas and intern save foreign exchange. One estimate suggests that even if five percent of India’s population opts for solar cooking then foreign exchange worth more than Rs. 250 Crores per year can be saved. Solar cooking preserves forests by saving firewood. This is must for national development. Adoption of solar cooking technologies will generate many employment opportunities. In rural families mostly the responsibility of collection of firewood rests with children and is one of the reasons for school drop outs. Use of solar cooking can save these children from exploitations and bring them back to school, which they deserve. With Kyoto Protocol coming in force and proposed mechanisms like CDM (Clean Development Mechanism), chances of fetching huge foreign investments and grants are excellent. Promoting solar cooking in a big way can increase India’s energy security. To cope with the speed of modern life there are many versions of solar cookers now available in India, to suit the requirement of every family. In addition to old box design of solar cookers (ovens) there are new breed of parabolic domestic and community cookers. India has to its credit the world’s largest solar cooking system at Tirupati cooking 30,000 meals per day. Generating awareness about these different solar cooking alternatives can generate excellent market for the new entrepreneurs in the field.