The objective of the present work is to conduct a worthwhile experimental study of the performance of a parabolic solar concentrator for solar cooking. The literature survey briefly highlights the standard performance tests of solar cookers and gives the experimental studies obtained by some authors. Our experimental device, made from simple means using local materials, consists of a parabolic concentrator having a 0.80 m diameter and 0.08 m depth as well as a cylindrical absorber with a 0.10 m diameter and is 0.20 m long. The testing period started on April 24th, 2014 and continued till July 10th of the same year, in Rabat (33°53′ N, 6°59′ W), Morocco. The average ambient temperature is 24 °C. The results show that using synthetic oil as the heat transfer medium has achieved a maximum temperature of 153 °C against 97 °C with water. The overall heat loss coefficient is estimated to be 17.6 W m−2  °C−1. The energy and exergy efficiencies are, respectively, 29.0–2.4% and 0.1–0.5%. Adding a glass cover on the front face of the absorber improved the maximum temperature by 15 °C. Automatic two-axis sun tracking system also increased the maximum temperature by 13 °C compared to manual tracking system.

Background: In an ever-changing world where needs increase daily due to economic growth and demographic progression, where prices are unstable, where reserves are running out, where climate change is topical, the energy issues are increasingly marked by the question of sustainability. In many developing countries, wood and subsidized butane are the main sources of energy used for cooking in households. The use of solar energy in domestic cooking becomes unavoidable. Several models of solar cookers have been proposed, but most of them dealt with box and oven types of solar cookers without storage. Methods: This paper presents a dynamic thermodynamic model of a parabolic solar cooking system (PSCS) with heat storage, along with a comparison of the model solution with experimental measurements. The model uses various thermal resistances to take into account heat transfer between the different parts of the system. Results: The first experimental setup consists of a parabolic concentrator (0.80-m diameter and 0.08-m depth) and a 1.57-l cylindrical receiver. The second experimental setup is composed of a parabolic concentrator (1.40-m diameter and 0.16-m depth), the same receiver, and a 6.64-l heat storage. Tests were carried out in Rabat, Morocco, between April 24 and July 10, 2014, and between May 15 and June 18, 2015. Synthetic oil is used as a transfer fluid and a sensible heat storage. Conclusions:Comparison between predicted and measured temperatures shows a good agreement with a relative error of ± 4.4%. The effects of important system design and operating parameters were also analyzed. The results show that a 50 W m −2 increase of the daily maximum solar radiation increases the storage temperature by 4°C and a 5% increase of the receiver reflectance or absorptance improves the maximum storage temperature by 3.6 and 3. 9°C, respectively. Optimizing the aspect ratio of the receiver to 2 gives a maximum storage temperature of 85°C. Increasing the thermal fluid mass flow rate from 0 to 18 kg h −1 , or the receiver thermal insulation from 0.01 to 0. 08 m, increases the maximum storage temperature by 65 and 17°C, respectively.

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