Saad Odeh", Mechanical Engineering Department/ Hashemite University Salem Nijmeh, Mechanical Engineering Department/ Hashemite University M. Sami Ashhab, Mechanical Engineering Department/ Hashemite University Yousef Zakaria, Mechanical Engineering Department/ Hashemite University Ahmed Amra, Mechanical Engineering Department/ Hashemite University

Jordan imports most of its energy demands in the form of crude oil and petroleum products. To meet the country’s future increasing energy demands some of the conventional thermal energy systems are required to be replaced by renewable energy systems. Currently the share of renewable energy in the total energy consumption is around 1%. It is expected that with increasing scientific and technological capacities in the field of renewable energy in Jordan, this share will rise up to 15% in the year 2010 [1]. A very promising application of solar energy in Jordan is its use for low and moderate temperature application such as food canning, paper production, air­conditioning, and sterilization. It was shown by many researchers that some types of solar energy systems are capable of producing the energy level required by different industrial processes. Parabolic-trough solar water heating is one of a well proven solar energy technology which is being used on a commercial scale to produce heat for industrial and residential applications. Hot water at temperatures (50-56°C) was produced by a field of 1584 m2 parabolic collector area to supply housing buildings, a cafeteria, a laundry, and services building [2]. The average collector array efficiency was found to be about 0.61 at average beam radiation. Solar steam generation by a parabolic collector field was studied to supply an absorption cooling system and heating needs of a hotel [3]. The estimated collector field area was 100m2 (on the hotel roof) to deliver steam at 144°C, and 4 bar. Evacuated CPC (compound parabolic concentrator) collectors with non-tracking reflectors were compared with two novel tracking collectors: a parabolic trough and an evacuated tube collector with integrated tracking reflector [4]. The CPC mirror was mounted inside the evacuated tube and hence protected from environmental influences. The efficiency of this type of CPC collector, at temperature of 300 °C, with anti-reflective coating of the glass tube, and a selective absorber coating, may reach up to 0.65. This allows for application in industrial process heat generation, high efficiency solar cooling and power generation systems. Simulation and modeling of direct steam generation parabolic trough collector (high pressure) were carried-out by many researchers [5, 6]. This type of collector was integrated in an electric power generation model in order to evaluate long term performance at different locations in Jordan [7, 8]. The study showed that such type of system could operate efficiently in Jordan. A simulation program was developed to study the thermo-hydrodynamic performance of a solar industrial water heating system with a back-up boiler and thermal storage tank [9]. The model was used in a case study of a cloth factory in Jordan to supply steam at moderate temperature and pressure to an existing factory processes. The study showed significant increase in annual performance (about 12%) when using N-S axis solar tracking mode rather

* Corresponding author, email: sodeh@hu. edu. jo or saad_odeh@hotmail. com, mail address: Mechanical Engineering Department, Hashemite University P. O.Box 150459, Zarqa 13115, JORDAN

than E-W tracking mode. The effect of thermal storage tank on system daily operation was studied for winter and summer periods. The performance evaluation of solar industrial water heating system in Jordan showed its applicability for different regions of the country. It was found that by adopting seasonal tracking, solar energy contribution and collector field performance will increase significantly.

Abdullah and Nijmeh [10,11] conducted a detailed study on solar tracking surfaces in Jordan. They designed and constructed an electromechanical sun tracking system based on the open loop method of control. The collected solar energy was measured and compared with that on a fixed surface. The two-axis moving surface showed an increase in the collected daily total energy of up to 41%. This gain is significant and justifies the use of tracking surfaces in certain applications of solar energy in Jordan.

In this paper a single tracking axis parabolic trough collector is designed and constructed for moderate heat load applications: such as domestic space air­conditioning and small factory process heat. The solar tracking collector is designed to be self powered for its tracking and water pumping systems.