Compressed air systems: Factors affecting the adoption of measures for improved efficiency

The sustainability and competitiveness of industrial activities may strongly rely on increased energy efficiency. In that, compressed air could be one of the most expensive forms of energy in industry because of its low efficiency. Nonetheless, compressed air is widely used, and is considered as relevant in many facilities, accounting for even more than ten per cent of industrial electricity consumption in the EU, in US and in China. Moreover, it should be noted that the life-cycle cost of a compressed air system is mostly covered by the operating costs, so that most of the measures to lower energy consumption pay for themselves almost immediately, producing relevant monetary savings. Nevertheless, several studies show that the adoption rate of such Energy Efficiency Measures (EEMs) is still low. For this reason, we have carefully reviewed scientific and industrial literature over EEMs for Compressed Air Systems (CAS), so to get useful insights into the main factors leading to their adoption. Our study lays a good foundation for a novel framework aimed at describing and characterising EEMs in CAS, revealing that, so far scientific and industrial literature has mostly presented energy and economic factors, thus giving little room to other factors that still could be quite relevant for an effective EEM adoption, such as compatibility of the measure within the production system (e.g., adaptability to different conditions, presence of different pressure loads), complexity of the production system (e.g., accessibility for operational activities, expertise required for implementation), observability of the performance (e.g., impact on air quality and/or safety). The framework could result in a valuable tool offering different perspectives in the decision-making of industrial managers and technology suppliers, as well as industrial policy-makers.