> Evacuated tubular collectors

In the period from 1975 to 1990 the group pioneered the development of evacuated tube systems using graded refractive index coatings, and tested many designs which had features which are now found in many commercial units. Since 1980 the Nitto and Shiroki companies in Japan produced hot water solar collector using Sydney University designed evacuated tubes (Fig. 1). These were also exported to Europe for use in collector systems. Even today, manufacturers such as Microtherm in Europe advertise the 'Sydney Collector' which recognises the contribution made by this group.

Fig. 1: Figure Japanese collector system using University of Sydney evacuated tubes.

More recently newer design evacuated tubes have been licensed for production to Turbosun Ltd. In China and commercial production of systems based around this tube have begun. Solahart Industries are introducing a new collector design using Turbosun tubes of very high efficiency. Solahart are working with the University to continue to improve the optical and thermal aspects of the design (Fig 2.).

Fig. 2: Current Solahart evacuated tube collector design using University licensed tubes.