Environmental assessment of domestic boilers: A comparison of condensing and traditional technology using life cycle assessment methodology

This study has carried out a life cycle assessment of two different domestic natural gas boilers in Italy, taking into account 3 different climatic regions and two dwellings with different energy classes. The aim of this research was to compare traditional and condensing boiler technologies. Primary data relating to the two products under analysis was supplied by an international boiler manufacturer, whilst the Ecoinvent database v2.2 was used as a secondary source of data. The assessment was performed using the CML and Cumulative Energy Demand (CED) methods, by considering the categories required by “Environmental Product Declaration” (EPD) certification systems. The results of the analysis show that on average, the condensing technology has a 23% lower environmental impact than its traditional counterpart for each scenario in the six impact categories considered. This is essentially due to its lower fuel consumption during the use phase and the lower levels of CO and NOx emitted during the combustion of natural gas. The study also shows that the use phase is by far the biggest contributor to the environmental impact, and on average is responsible for more than 90% of the total impact.