Micro (Mini)-Channels and Their Applications in Solar Systems

Abstract

This chapter presented micro (mini)-channels and their applications in solar systems. Two types of channels, micro (mini)-tubes and micro (mini)-heat pipes, have been presented, and the performance of their use in solar systems has been illustrated by studies in the literature. For solar thermal systems, the integration of micro (mini)-channels can increase significantly the thermal performance that achieves an increase of 28% compared to conventional channels. For PVT systems, the use of micro (mini)-channels enhances also the electrical output by decreasing the temperature of PV panels. Consequently, the use of these channels increases the overall efficiency of PVT systems that can achieve the overall efficiency of around 70%. Furthermore, in this paper, the use of micro-channel has been illustrated by the investigation of a novel solar PVT loop heat pipe employing a micro-channel heat pipe evaporator and a PCM triple heat exchanger. This illustration showed environmental parameters (i.e. solar radiation, air temperature, wind velocity), structural parameters (i.e. glazing covers, number of the absorbing heat pipes, PC cell packing factor) and the variable inputs (i.e. water inlet temperature, mass flow rate) that can influence the overall efficiency of the novel PVT system. This chapter showed that application of micro (mini)-channels in solar systems is promising, and their integration in solar technologies can enhance significantly their performance and their market share.