74
B. S. Mukesh et al.
Fig. 5.10 Inlet and outlet temperature from the single pass CSWH system
The theoretically predicted geometric concentration ratio is 115 but from the experiment the flux concentration ratio obtained is 94. The obtained outlet experimental
temperature can be used for validation of the numerical model of this system.
5.6 Conclusions
A concept of concentrated solar water heater (CSWH) system is proposed, designed
and developed from easily available and low cost materials. This is based on the point
focusing concept using parabolic dish onto a small receiver. This aims to reduce the
exposed surface area of receiver to ambient and thus, reduce heat loss. The presented
CSWH system shows a thermal efficiency of about 59% at a lesser power input and
smaller HTF mass flow rate as compared to system LMA13 as in Table 5.1 Ayompe
and Duffy (2013a), which is a non-concentrating solar water heating system with
thermal efficiency of 44%. The theoretical geometric concentration ratio is 115 and
from the experiments conducted a flux concentration ratio of 94 is obtained. The first
level design with the measured efficiency of about 59% compares well with that of
the existing systems. Further improvements are foreseen with a cavity to mitigate the
direct heat loss. Due to the ease of the fabrication, easy availability of the materials
used and low cost the presented CWSH system can be widely used.
B. S. Mukesh et al.
Fig. 5.10 Inlet and outlet temperature from the single pass CSWH system
The theoretically predicted geometric concentration ratio is 115 but from the experiment the flux concentration ratio obtained is 94. The obtained outlet experimental
temperature can be used for validation of the numerical model of this system.
5.6 Conclusions
A concept of concentrated solar water heater (CSWH) system is proposed, designed
and developed from easily available and low cost materials. This is based on the point
focusing concept using parabolic dish onto a small receiver. This aims to reduce the
exposed surface area of receiver to ambient and thus, reduce heat loss. The presented
CSWH system shows a thermal efficiency of about 59% at a lesser power input and
smaller HTF mass flow rate as compared to system LMA13 as in Table 5.1 Ayompe
and Duffy (2013a), which is a non-concentrating solar water heating system with
thermal efficiency of 44%. The theoretical geometric concentration ratio is 115 and
from the experiments conducted a flux concentration ratio of 94 is obtained. The first
level design with the measured efficiency of about 59% compares well with that of
the existing systems. Further improvements are foreseen with a cavity to mitigate the
direct heat loss. Due to the ease of the fabrication, easy availability of the materials
used and low cost the presented CWSH system can be widely used.