There is a huge gap between the broad concept of circular economy (CE) and its practical implementation in the industrial sector due to several types of barriers, which shall be led back to the lack of consistent and precise information about resources, products, and processes. Without a proper information flow, it is impossible to quantify circular initiatives, both in comparison with the actual linear situation or with circular alternative opportunities. A proper quantification of circular initiatives allows the assessment of economic, environmental and social benefits and the preventative identification of potential barriers and relative solutions, monitoring the risk associated with circular investments and supporting the decision-making process. This paper describes a new tool to ensure the quantification of circular initiatives and the method to define it. It is a new Circular Business Model (CBM) visualization tool, which overcomes the main limitations of the existing models able to explain CE concepts but not to boost its practical implementation in industry. The new CBM visualization tool can be adopted in every industrial sector to highlight circular opportunities that are still hidden or unexploited or to select the best CE strategy. The proposed CBM visualization tool differs from the previous diagrams in two main characteristics: (i) the possibility to quantify resource flows and important indicators representing energy consumption, environmental and social impact, and (ii) the focus, which is not only on the product, but on the whole system, involving also the process, the company and the entire supply chain. The methodology to adopt and adapt the proposed model to different scales is described in detail. To provide a practical example, the model was qualitatively applied to a generic technical product to highlight its potential in the identification and quantification of circular activities.

Although the circular economy (CE) is recognized as a source of value creation, there is a huge gap between the vast concept of CE and its practical applications. Particularly, the lack of information and performance indicators, in terms of economic, environmental and social aspects, does not allow for the assessment of the level of circularity of the products, processes or companies. Further development of other circular activities can be limited for this reason. In addition, intelligent assets arising with the digital transformation within the “Fourth Industrial Revolution (I4.0)” can support CE to provide these lacking aspects. Thus, the objective of this paper is to highlight how and how much the circular business models are enhanced by intelligent assets from I4.0, considering several case studies found in the literature, and through the application of an assessment tool with secondary data from the selected case studies. According to the tool, the CE principles are extended to the entire product lifecycle, from product design to product utilization, within the transition to novel business strategies. Two of the considered case studies are represented in the assessment tool, as examples, to demonstrate how intelligent assets can support circular economy in the design, assessment and comparison of circular initiatives. The visualization of existing innovative business models based on CE and enhanced by intelligent assets allows for the complete and effective evaluation of materials, products, assets and processes, due to the fact that information and indicators can be collected to measure and monitor circular efficiency.

The development of sustainable and innovative solutions for the production and supply of energy at district level is nowadays one of the main technical challenges. In the past, district heating and cooling networks aimed to achieve greater energy efficiency through the centralization of the energy production process but with relevant losses related to heat transport. Moving towards a higher share of renewables and lower demand of primary energy requires redesign of the energy district networks. The novel concept of cold district heating networks aims to combine the advantages of a centralized energy distribution system with low heat losses in energy supply. This combined effect is achieved through the centralized supply of water at relatively low temperatures (in the range 10–25 °C), which is then heated up by decentralized heat pumps. Moreover, cold district heating networks are also very suitable for cooling delivery, since cold water supplying can be directly used for cooling purposes (i.e., free cooling) or to feed decentralized chillers with very high energy efficiency ratio. This paper provides a preliminary literature review of existing cold district heating networks and then qualitatively analyses benefits and drawbacks in comparison with the alternatives currently used to produce heat and cold at district level, including the evaluation of major barriers to its further development.