The main components of the system are: solar collectors, thermal storage tank, auxiliary heater, single-effect absorption chiller, and building. The flow diagram of the system is given in Figure 1.

The system is modeled using a TRNSYS simulation program [5]. The weather data of Assab is extracted from the result of experiment, while the weather data of Nicosia is extracted from Meteonorm [6].

Solar collectors

The characteristics of two types of solar collectors, evacuated tube, ESC and double­glazed, DGC solar collectors are given in table 1.

Storage tank

Two storage tanks with a volume of 2m3 and 1.5m3 are selected for the two systems, which include evacuated tube collectors and double-glazed flat plate collectors, respectively.

Auxiliary heater

An auxiliary heater is used to add energy to the system whenever the energy delivered from the solar energy is not enough to overcome the energy required. The heater has a maximum capacity of 25 kW.

Absorption chiller

The full description of the single-effect absorption chiller and its diagram is given in many literature studies and therefore excluded here.

Building

The model uses TYPE 19 (Transfer Function method). The model calculates energy loads based only upon the net gains or losses from the space. The loads are considered independent of the heating or cooling equipment operation. The user specifies the set temperature for heating or cooling. The program determines the energy necessary to keep the room at the set points.

The details of the building are:

Assab is located on Latitude 13.07°N, longitude 42.63°E and altitude 10m and Nicosia is located on Latitude 35.15°N, longitude 33.35, and Altitude 5 m.

The building has a floor area of 92 m2, doors area of 13.3 m2and windows area of 4.78m2. Each wall is constructed of 0.24m common break and 0.02 m cement plaster. The floor consists of selected soil, stone and concrete coating (0.20m each) and cement tile (0.02m) and the roof consists of corrugated sheet metal (0.002m), stud and cheap wood ceiling (0.04 m). The doors are made of wood with 0.03 m thickness and the windows are made of 0.006m clear single-glass.

Insulation with different thickness is added to the walls, roof and floor and the doors and the windows have overhung and wing walls. The thermal properties of the building materials are taken from [7] and [8]. The heat transfer through the floor of this particular building is calculated by the technique used in Thermal Performance of Building-Heat Transfer via the Ground-Calculation Manual [9].