Towards context-independent indicators for an unbiased assessment of environmental sustainability in higher education: An application to Italian universities.

Higher education institutes (HEIs) are important drivers for the development and implementation of best practices for environmental sustainability. However, reliable indicators are needed to objectively evaluate the environmental performance of HEIs and their policies. The present paper aims at identifying suitable indicators for unbiased comparisons among different HEIs and for the identification of temporal trends in terms of environmental sustainability performance. At this aim, sustainability reports made publicly available by 24 Italian HEIs over a 10-year period were considered. Normalization of sustainability variables such as the annual electrical and thermal energy consumptions, related greenhouse gas emissions, and water consumption, against context-specific factors such as the number of users of each university, latitude, illuminance, heating degree days (HDDs) and cooling degree days allowed identifying the actual possible disturbance of the same variables. HDDs were found to positively affect the thermal energy consumption and the related CO 2 emissions. Based on this, a novel indicator was formulated where the actual value of thermal energy consumption and the related CO 2 emissions are divided not only by the number of users but also by the HDDs of the HEIs' locations. Indeed, this is a remarkable finding that, prior to confirmation with data from world HEIs, could be implemented in world university green ranking systems for improved and less biased sustainability assessments. [Display omitted] • Context-independent indicators allow unbiased sustainability comparison among HEIs. • Context-independent indicators were identified through coefficients of variation. • Per capita thermal energy consumption needs to be divided by heating degree days. • Per capita CO 2 due to thermal energy needs to be divided by heating degree days. [ABSTRACT FROM AUTHOR]