Economic, energy and environmental life cycle assessment of a liquid flow window in different climates

In this study, life cycle assessment was applied to a novel liquid flow window, based on the cases of sports center application in different climates of Hong Kong and Beijing. The economic, environmental and energy impacts of selected window frame material, the expected lifetime and cost of the working fluid and accessory components were assessed. It was found that the use of wooden frame could be advantageous in that the cost payback time is less than 1.4 years in Hong Kong and well below 5.5 years in Beijing. Nevertheless, when stainless steel frame was in use, the cost payback period would increase to 3.0 and 7.0 years for Hong Kong and Beijing respectively. The lengthy payback time of Beijing is mainly caused by the use of expensive anti-freezer in the liquid circulation. Sensitivity test showed that by taking efforts to lower the material costs and to prolong the lifetime of working liquid, the cost payback time in Hong Kong and Beijing could be reduced to 1.5 and 3.6 years or lower.