DESIGN OF PARABOLIC SOLAR COOKER

Charcoal and firewood are today’s most accessible sources of energy for the preparation of daily meals and heating water for bathing. However, due to the increase in population, there is also an increase in the rate of cutting down trees which leads to the problem of deforestation which is also directly proportional to soil erosion. Apart from deforestation, the use of charcoal and firewood also produces greenhouse gases such as carbon dioxide (CO2) and methane (CH4) which are major causes of global warming, climate change, and some health problems such as tuberculosis, lung cancer, asthma, and bronchitis in humans. Therefore, the main object of this research project was to design a parabolic solar cooker which will be the alternative to the use of charcoal and firewood, and the designed parabolic solar cooker have new physical features which increase the systems efficiency and good thermal storage. During the process, all factors such as material selection and design were considered accordingly in order to build finest parabolic solar cooker. The dimensions of the designed parabolic solar cooker were also determined according to other high performance parabolic solar cookers and the placement of pot stand was compared to the theoretical focal spot. And also, there was a task of finding relevant materials for heat storage. After investigation latent heat materials shows a better potential for this application, especially for their ability to store a lot of energy at constant temperature. The influence of solar tracking inaccuracy was also investigated as well, and shows that by choosing a large absorber, it was possible to both reduce the influence of these inaccuracies and of the solar angles. The design was then simulated using SOLIDWORKS and MATLAB. And the results produced was then compared with already existing parabolic solar cookers which has high performances, and from that comparison, the results conclude that a new design of parabolic solar cooker has proved its ability in terms of thermal performance and achieving high efficiency of 0.796.
Keywords: Solar cooking, Parabolic solar cooker, Solar cooker design, thermal performance, Energy, Malawi.

Apart from deforestation, the use of charcoal and firewood also produces greenhouse gases such as carbon dioxide (CO2) and methane (CH4) which are major causes of global warming, climate change, and some health problems such as tuberculosis, lung cancer, asthma, and bronchitis in humans. Therefore, the main object of this research project was to design a parabolic solar cooker which will be the alternative to the use of charcoal and firewood, and the designed parabolic solar cooker have new physical features which increase the systems efficiency and good thermal storage. The influence of solar tracking inaccuracy was also investigated as well, and shows that by choosing a large absorber, it was possible to both reduce the influence of these inaccuracies and of the solar angles. And the results produced was then compared with already existing parabolic solar cookers which has high performances, and from that comparison, the results conclude that a new design of parabolic solar cooker has proved its ability in terms of thermal performance and achieving high efficiency of 0.796.

The study was conducted at Malawi University of science and technology (MUST). Which is located in Goliat, Thyolo District, TA Ngolongoliwa which is made of a population of 33,839 is according to the national demographics’ statistics (2018) which most of the people rely on charcoal and firewood as a source of energy for cooking and heating water for bathing. Malawi University of Science and Technology (MUST) is found at coordinates of 15.9020S, 35.2168E, and is 36.6 kilometers from the center of Blantyre city.

Traditional authority: TA Chimaliro

District: Thyolo

Coordinates: -15.9729, 35.19975