The performance of a solar water pump which works on the basis of vapour ge
nerated by a flat-plate solar collector of exposed area 1 m(2) has been stu
died for three different discharge heads, namely 6, 8 and 10 m. The design
and experimental results of the pump which entailed detailed calculations t
o obtain the optimal volumes of the vessels, are presented in this paper. T
he inclusion of a storage tank for storing the vapour facilitates greater f
reedom in the pump's operation and thereby improved its performance. The pr
essure in the collector system in both theory and experiments prove that th
e various tank sizes which were suitably designed for the pumping system, a
re found to be optimum. (C) 1998 Elsevier Science Ltd. All rights reserved.