MANUFACTURE AND COST OF VACUUM GLAZING

The vacuum glazing project at the University of Sydney has progressed to the point where the main Features of the vacuum glazing design are determined well. Over 500 glazings with areas up to one square meter h ave been formed. The stresses to which these glazings are or may be ex posed have been studied extensively. The durability of the glazing str ucture and the internal vacuum has been demonstrated. Vacuum glazing o f the type designed and formed at the University of Sydney has a cente r-of-glazing thermal conductance as low as 0.85 and 1.2 Wm(-2)K(-1), f or glazings with two and one internal low emittance coatings, respecti vely. A method for the manufacture of the vacuum glazing is outlined f rom which the cost to manufacture the glazing can be estimated. A cost at the factory of about $40+/-7 m(-2) for vacuum glazing using two sh eets of low-e glass and about $32+/-6 m(-2) for glazing using one shee t of low-e glass is obtained, when production volume is approx. 10(5) m(2)yr(-1) and is partially automated. This is about 25% higher than t he estimated manufacturing cost of the high thermal resistance, argon filled, double glazing utilizing low-e glass, which are currently in p roduction and being sold in the United States, Europe and Japan. These glazings typically have center-of-glazing thermal conductances of abo ut 1.1 Wm(-2)K(-1) or more.