Low energy–low carbon acute hospital engineering design and operation in the UK : analysis of the impact of In-Use

This thesis introduces an innovative contribution to the low energy - low carbon design of acute hospitals in the UK. The need for innovation in acute hospital design arises from the consistently poor energy and carbon performance of the health care estate over a period of nearly three decades. This poor performance translates into a situation where overall consumption of energy in the health care estate has remained largely unchanged over that period, despite substantive improvements in the asset specifications of these facilities. With respect to the commitment made by the British Government to reduce carbon emissions under the Climate Change Act (2008) this situation is clearly unacceptable, because that commitment requires an 80% reduction in carbon emissions by 2050. Of equal concern has been the poor predictability of energy forecasts for new buildings, where the apparent difference in performance between design and what is actually achieved In-use can be substantial. In terms of energy consumption and the associated carbon emissions, the author’s research has discovered that the issues of poor In-Use performance and poor predictability of performance in acute hospitals are directly linked. The central causal factor that leads to both is a poor understanding of clinical user practices and the impact of those practices on the design and engineering of the hospital. The research identified that without such an understanding it means that hospital planners, designers and engineers are required to make substantial assumptions concerning In-Use during the design process, most notably concerning occupancy presence and the diversity of occupancy. The author’s investigations found that it would be possible to use simulation to replicate how acute hospitals operate by utilising clinical process information contained in operational policy documents. It was also discovered that the data derived from clinical information systems could be used to run the simulation. It is the unique methods developed by the author that are his contribution to new knowledge. One method developed by the author is called Occupancy Analytics. The method enables the author to predict occupancy presence and diversity within a range of probabilities at any hour of the day within the hospital. A second method enables these values to be modelled within another simulation called the Whole Facility Energy Model. Using both models in sequence the author discovered how to directly correlate the impacts of operational policies and working practices to energy consumption and the associated carbon emissions. Using this new knowledge, the factors that determine occupancy presence and diversity were then investigated. The author reasoned that if these could be managed then it would be possible to optimise the engineering design, and the consequential energy consumption and the associated carbon emissions. Through the use of a case study that is both revelatory and longitudinal (Yin, Op Cit) the author demonstrates how this objective was achieved. Finally, using the results from both Occupancy Analytics and Whole Facility Energy Modelling the author also discovered that it would be possible to establish norms for energy and carbon performance based on each patient type using the clinical services of the acute hospital. In the case study, the author demonstrates how this form of analysis could be used to establish the basis for departmental energy budgets, which he envisages could make an important contribution to the future optimisation of low energy – low carbon performance of acute hospitals in the UK