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Limited fossil resources and environmental problems imply that development of solar thermal appliances will play major role in incoming years, especially to meeting domestic energy requirements. The cooking energy demand, which is the largest primary energy-consuming sector and, are continuously increasing. This research paper deal with the temperatures and efficiency mapping of a realized parabolic solar cooker tested in Saharan region of Ghardaîa (Algeria) climatic conditions. Using Black body temperature equation's based on Stefan-Boltzmann law, maps for focal areas receiver temperatures of the cooker are obtained by converting obtained results from optical simulation to thermal values. Several maps are generated through present study for both summer and winter with clear and cloud skies. It was found that cooker temperature values obtained during experimentations and that estimated using the proposed approach has good agreement. The rate of using the cooker from Northern to Southern regions of the country was not identical. For cloudy skies, the major area of the country is favorable for the use of the cooker during winter months. For clear skies, the mapping results indicate that the realized cooker is efficient in all the country throughout the summer season with temperatures exceeding 110 °C. The use of the cooker will be reduced by going in South to North regions during the winter months, depending on the amount of solar radiations received.

Algeria has an important solar irradiation potential especially in the southern area. Technically, the hard climate of the region makes exploitation of this energy very difficult; thus, looking for adequate and innovative solutions is a necessity. In this paper, we propose and describe a new single axis sun tracking system that has a moveable absorber which can be adjusted in order to minimize the optical losses caused by the cosine effect in parabolic trough concentrators (PTC). This new system was tested in the region of Ghardaïa (32.48°, −3.66°, 502 m), which is 640 km to the south of Algiers. First, a theoretical study and simulations were carried out using trnsys software. After simulations and design calculations, the different parts of the prototype, the mechanical structure and the electronic cards, were implemented. For the data collection system and the control system, many sensors were installed for those purposes. A complete evaluation of the PTC was made according to the ASHRAE 93-1986 (RA 91). The obtained experimental results are in a good agreement with those obtained by simulation using trnsys software [S. A. Klein et al., see http://sel.me.wisc.edu/trnsys for trnsys version 16, Solar Energy Laboratory, University of Wisconsin-Madison, 2004]. The efficiency of the proposed sun tracking system lies between the efficiencies of a single axis and a two axes sun tracking systems. Efficiencies close to 50% were obtained.

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