Aggregated Data and Trends

The key themes identified in the transcripts are shown in Figure 5 below, which also shows frequency. Aggregation and analysis of qualitative data, generated by responses to all 10 questions, showed that of the 17 themes identified in the transcripts the most common was the environment (identified 15 times), followed by circular/circularity and economic (8); efficiency/energy efficiency (7), social and support (6), awareness, future, manufacture, and public sector (4), growth and market visibility (3), business, green procurement, target, and users (2) and tool (1). Considering the interests (i.e., all bar one have engaged with the CEDaCI project and take part in WGs and CCWs), expertise and roles within the organisations (5 are directly linked to sustainability, 3 are linked to overall efficiency and 1, sustainability-linked research) these results are not surprising; similarly, alignment of the themes with the individual participants reflected the type of organisation with which they work: for example the (A) (who works for a corporate global IT producer) focussed on efficiency, growth, manufacture, and targets; (B) and (E), who work for SMEs specialising in refurbishment/second life products and recycling, focused on the three tenets of sustainability, education, and circularity, as did (C), who also commented on the public sector and works for a national non-profit organisation; (D) and (G) work for a non-profit global open-source IT provider, and both referred to sustainability-linked criteria and the future growth; (F) (who works in a university) focused on the environment and economics as did (H), the technical consultant who also spoke of manufacture and business. Finally, (I) who works for an advisory body, mentioned the broadest range of themes, including sustainability and circularity, business, manufacture, planning, public sector, the future, and targets. *Sustainability* **2021**, *13*, x FOR PEER REVIEW 20 of 23

**Figure 5.** 17 Key themes identified in the semi-structured interviews by frequency. **Figure 5.** 17 Key themes identified in the semi-structured interviews by frequency.

This paper began with a brief history of computing and the data centre industry, outlining established thought process and practice in the general engineering profession and data centre industry. This review was necessary in order to contextualise the scale and nature of the current and future challenges facing the sector unless there is a significant change from a linear to circular economy. The paper then describes two methods (Design Thinking and the Double Diamond Framework for Innovation), which underpinned CEDaCI, a unique project that was set up to kick start the Circular Economy for the Data Centre Industry. People and stakeholder engagement are central and critical to the design methods; however, the DCI is very fragmented and silo working is the established practice in the various sub-sectors so there was a risk that the project would be compromised, or fail to deliver, because of lack of engagement. The project team used various strategies to engage stakeholders; this has proved successful so far, and the CEDaCI team has built a Network with 100 members. All Working Groups meetings and Co-creation Workshops are also well-attended, and participants appear to fully engage

In order to assess the impact of the project, the level of stakeholder engagement and the success of the design methods, quantitative and qualitative data were collected and analysed via an on-line survey and semi structured interviews. The overall response from this research indicates that the project is very well received and is fulfilling aims so far; the enormous scope of the project means that creating a sectoral circular economy in three and a half years is unrealistic but the project is raising awareness across the sector and demonstrating that a CE is possible. For example, participant (D) volunteered that "*CEDaCI has created an awareness and an interest to look into the topic of the circular* 

The participants' response to the WG meetings and CCWs has exceeded expectations; the aim of these events to was to bring together actors from across the DCI

*economy. That's a huge success. That will create a big change on the market*".

with the project team and each other throughout.

**5. Discussion** 
