Explorative study on Compressed Air Systems' energy efficiency in production and use: First steps towards the creation of a benchmarking system for large and energy-intensive industrial firms

Compressed Air Systems (CAS) are one of the most common and energy intensive utilities in industry, representing up to 10% of the industrial energy needs. Thus, they can be considered as one of the main target systems while planning energy efficiency actions implementation in industry. Nevertheless, most of the available benchmarks of energy consumption are based on nominal data, thus referring to the quality of the design, while benchmarks based on measurements under actual operating conditions are not yet available.In accordance with the Italian transposition of the European Directive 2012/27/EU (i.e. Legislative Decree 102/2014), large and energy-intensive business organizations must perform energy audits at least every four years starting in 2015 and the Italian Energy, New Technology and Environment Agency (ENEA) has the task of collecting and analysing them. In this context, a data collection focused on CAS has been carried out and the subsequent data analysis, focused on nine most promising industrial sectors, has allowed to assess the current state of the art of CAS's energy efficiency in Italy and to design a possible benchmarking system. Such a system is composed of a set of indicators and a benchmarking visual tool in the form of a matrix. In particular, results related to the Manufacturing of basic metals will be presented for sake of brevity. In this paper we present the results obtained from both the data analysis and the first application of the proposed benchmarking system, together with next steps for the creation of reliable sectorial and cross-sectorial benchmarks.