Though cost reduction is a key duty of public infrastructure project practitioners to ensure taxpayers get more for less, the literature has been drawn away from this subject. Cost performance has been seen as synonymous with reducing cost overruns that stem largely from projects being insufficiently planned. Better front-end definition of these projects would increase their estimated costs and thus make it more likely for the actual cost to match. However, though this improves cost performance on the face of it, it can fall short of delivering value for money for the taxpayer. It neglects reduction of cost during the planning of projects through optimisation of their design and delivery, something that frees up funding for other important projects and is thus of considerable value to society. This is even more crucial for the larger, more complex projects like nuclear decommissioning projects/programmes (NDPs), where their cost is higher and thus the value of cost reductions greater. However, the infrastructure projects realm generally lacks understanding of the key areas for cost reduction opportunity: the cost drivers. Moreover, the cost reduction opportunities themselves are not clearly defined, with researchers tending towards quantitative methods but doing little to present project teams with implementable cost reduction solutions. Benchmarking is a tool that can be used to identify how the best-in-class projects reduce their cost, but it is not yet known if complex project teams actually perform benchmarking effectively. This could justify underperforming NDPs as compared to similar but higher performing complex project industries like offshore oil & gas decommissioning projects (OGDPs). Therefore, this thesis aimed to investigate the cost drivers of infrastructure projects and the cost reduction and benchmarking practices of NDP and UK OGDP practitioners.
Three stages of research were conducted to meet this aim. In the first stage, an integrative literature review of the cost drivers of infrastructure projects was conducted. It presents a novel definition, a taxonomy, and conceptual framework of cost drivers. The conceptual framework highlights those from the taxonomy that are controllable, i.e., able to have their cost reduced. This formed the basis of the second stage of research, where a single-case study of a UK NDP was conducted to determine how cost is reduced in relation to the cost drivers. To uncover this in more detail, this stage utilised a practice theory lens to understand the actuality of cost reduction. It provides seven practice-based cost reduction solutions that extend previous knowledge by offering insights both into what can be done to reduce cost in the planning of complex projects and also how these solutions are actually developed and implemented. The third stage of research uses practice theory again to understand the actuality of benchmarking in complex projects. Semi-structured interviews were conducted with project practitioners from UK NDPs, Continental Europe NDPs, and UK OGDPs, to find that the actuality of benchmarking – presented in the form of a novel five-domain qualitative and quantitative benchmarking framework – looks considerably different to the guidance. It shows that benchmarking needs to be adapted to better support complex projects teams in the identification of performance improvement solutions.
