The proposed size of collectors integrated PCM provided about 18 23% of total daily thermal energy requirements of the greenhouse for 3 4 h, in comparison with the conventional heating device.
Investment cost of the collectors is mainly decided by the size of the collector area.
The design parameters to determine the size of the collector were obtained by implementing a simulation model for double flow air solar collectors.
Likewise, increasing values of irradiance and size of the collector lead to higher values of thermal performance, although other parameters should also be considered for the final design of the system.
The size of solar collectors required to meet the demand depends on the local irradiation and device conversion efficiencies.
Unlike biogas, the availability of solar energy does not depend on local resources; thus, it is evaluated based on the size of solar collectors.
Thus, the results for each biogas configuration are presented in gigajoules of energy and that of solar energy is with the size of solar collectors meeting the demand in square meters.
Various performance factors such as solar fraction, collector efficiency and primary energy savings are evaluated to optimize the key system design variables which include collector tilt, storage volume, type and size of the solar collector.
From the conducted investigations it has been evidenced that an optimal size of back-mounted collector air-channel can be found with suitable tilt angle, corresponding to which the overheating of collectors can be controlled passively under stagnation conditions.
This raises issues about optimization of the size of a current collector and the area from which the current due to electrochemical reaction is collected [11, 12].
