ABSTRACT
All solar domestic hot water (SDHW) systems that do not operate with natural convection need a pump to force fluid through the collector. The most common type of pump used today, a centrifugal pump, is technically not very suitable for low-flow applications – but it is cheap. Other pumps have been used, with varying degrees of success. This paper presents data from measurements from the most commonly used pumps as well as others that have been used to a lesser extent or not at all for solar applications. These include pumps driven directly from photovoltaic units.
The pumps tested are decribed along with their advantages and disadvantages for low-flow systems. Consideration is taken of expected lifespan, noise and cost as well the measured data.
