Recently, considerable attention has justifiably been directed towards energy savings in buildings as they account for up to 20–40% of total energy consumption in developed countries. In the United Kingdom, studies have revealed that buildings’ CO₂ emissions for account for at least 43% of total emissions. Window panels are a major component of the building fabric with considerable influence on the façade energy performance and are accountable for up to 60% of a building’s overall energy loss. Therefore, the thermal performance of glazing materials is an important issue within the built environment. This work evaluates the impact of solar window films on the overall energy consumption of an existing commercial building via the use of a case study U.K. hotel and TAS dynamic simulation software. The study results demonstrated that the impact of window films on the overall energy consumption of the case study hotel is approximately 2%. However, an evaluation of various overall energy consumption components showed that the window films reduce the annual total cooling energy consumption by up to 35% along with a marginal 2% increase in the annual total heating energy consumption. They can also provide overall cost and CO₂ emissions savings of up to 3%.

Adverse effects of anthropogenic climate change has resulted in mitigation strategies geared towards curbing CO₂ emissions. Consequently, this has increased demand for more energy efficient buildings. Considerable amounts of studies have shown the existence of a significant discrepancy between estimated energy consumption by thermal simulation software and actual building operational energy; this is referred to as a ‘performance gap’. This work presents a method of improving the energy consumption estimate in an existing non-domestic building via the use of a case study UK hotel (Hilton Reading Hotel) and Engineering Development Solutions limited (EDSL) TAS thermal simulation software. The method involves evaluating consumption estimates through plant modelling, and modifying this result by surveying the site to verify the simulation data and including estimates of unaccounted building energy use such as catering services which can be significant in hotels. The energy consumption result for this case study building gives an estimate which is within 12% of the actual building consumption data. The result also demonstrated that such models can produce energy consumption estimates that are up to 23% more accurate than building regulation compliance models and that more accurate simulation consumption estimates can be achieved by accounting for more unregulated energy uses, for example, lifts, servers and small power load.

Several studies have highlighted Combine Heat and Power (CHP) systems to be one of the proven and reliable technologies that can improve the efficiency of heat and electricity generation. The extensive adoption of this type of technology is crucial in reducing building emissions globally and in the U.K. This work uses a dynamic simulation software to evaluate the effect of CHP on the energy performance of an existing U.K. hotel and subsequently an approach to aid in the selection of optimum CHP size. The outcome of the study indicated that CHP systems in hotel buildings can provide considerable economic and environmental benefits with either maximally-sized CHP founded on the building’s base heat demand or with reduced CHP size of more than 50% smaller than the estimated maximum size. The optimum size design can be obtained through evaluation of the relationship between the main performance parameters and their variation with CHP sizes.