Impact of window films on the overall energy consumption of existing UK hotel buildings

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%

Optimum size selection of CHP retrofitting in existing UK hotel building

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

Retrofit of a UK residential property to achieve nearly zero energy building standard

It is currently agreed upon that one of the major challenges in the construction industry is the energy efficiency of existing buildings. The World Meteorological Organisation (WMO) and United Nations (UN) have reported that the concentration of global atmospheric carbon dioxide has increased by an average of 50%, a record speed, from 2015 to 2016. The housing sector contributes to 45% of the UK’s carbon emissions. To help tackle some of those issues the recast Energy Performance Building Directive (EBPD) has introduced Nearly Zero Energy Buildings (NZEBs) in the coming years (including buildings that will undergo refurbishment/ renovations). This paper will explore the retrofitting of a UK residential dwelling using Thermal Analysis Simulation (TAS, EDSL) software by focusing on building fabric improvements and usage of on-site renewables. The CIBSE Test Reference Year (TRY) weather data has been selected to examine the performance of the building under current and future climate projections. The proposed design variables were finally implemented in the building altogether on TAS. The simulation results showed a reduction in the building’s annual energy consumption of 122.64kWh/m2 (90.24%). The greatest savings after this were achieved for the annual reduction in carbon emissions and avoided emissions, which were 84.59% and 816.47kg/CO2, respectively

Environmental performance assessment systems in the hotel industry

The present paper, which is conceptually embedded in environmental management theory, focuses on the question of monitoring and reporting environmental performance in the hotel industry. Its principal aim is to analyse the functioning, characteristics, and advantages of the performance assessment systems that are currently used in facilities belonging to international hotel chains. Specifically, the study, drawing on the content analysis technique, substantiates its claims by referring to concrete examples from the hotel industry (Scandic, Marriott International, Inter- Continental Hotel Group, Hilton Worldwide). Crucially, emphasis is placed on the practical problems related to the operation of such tools. The paper concludes by providing a number of recommendations on how to implement and run environmental performance assessment systems in hotels. In this way, it expands a fast-growing research on the practical dimension of hotel operation, thereby being of special interest to hoteliers and hotel managers

Impact of adding comfort cooling systems on the energy consumption and EPC rating of an existing UK hotel

Abstract: In light of the recent launch of the Minimum Energy Efficiency Standard and its expected impact on the commercial buildings sector, this study investigated the impact of adding cooling systems on the annual energy consumption, carbon dioxide emissions and energy performance certificate (EPC) rating of an existing UK hotel. Thermal Analysis Software (TAS) was used to conduct the study, and the baseline model was validated against the actual data. As is the current accepted procedure in EPC generating in the UK, the cooling set points of the guest rooms were set to 25 °C, resulting in a small increase in the annual energy consumption and emission rates, but not enough to change the energy performance certificate rating. Also, it was found that an improvement in energy consumption and energy performance certificate rating of the hotel would be achieved if the new systems replaced the existing heating systems in the guest rooms. Further simulations investigated more realistic situations, in which occupants may decide to keep their rooms at cooler temperatures. The results from this round of simulations showed considerable increase in the energy consumption and emissions of the building; however, these results would not be considered in the current approved procedure for EPC generating

Carbon emissions, and financial impacts from the incorporation of CHP and CCHP systems in existing UK hotel buildings

In recent years there has been an increasing interest in the incorporation of distributed energy resource (DER) systems such as combined heat and power (CHP) and combined cooling, heating, and power (CCHP) in commercial building applications as they have shown considerable environmental and financial benefits when compared to conventional energy generation. This paper aims to investigate the potential energy, carbon emissions, and financial impact of the size of co/tri-generation systems on a real case scenario of an existing UK hotel. The analysis is carried out using Thermal Analysis Simulation software (TAS) and a payback methodology is adopted to carry out the financial analysis. The results show that the average percentage decrease in carbon emissions with CHP is 32% and with CCHP it is 36%. Whilst both CHP and CCHP systems increase energy consumption in the building, the costs are reduced, and a CHP system contributes to a higher percentage of cost savings and shorter payback periods. The incorporation of a CCHP system leads to lower energy consumption for a similar-sized CHP system. Further simulations under future climate projections revealed that a CCHP system outperforms a CHP system

Discrepancy in Embodied Carbon Calculations for Concrete Materials

Abstract. Accurate assessment of embodied carbon is integral to understanding the environmental impact of building materials and promoting sustainable building practices. This process aids in prioritizing efforts to reduce emissions and mitigate climate change. Existing studies highlight discrepancies across various embodied carbon databases, causing uncertainty in assessments. Our study reveals significant differences in the calculated embodied carbon of materials, depending on whether they are assessed as a singular entity or as composed of individual components. Concrete, a major contributor to embodied carbon in construction projects, serves as our focus. We calculate the embodied carbon of concrete materials in a typical residential building using Life Cycle Assessment (LCA), a comprehensive method to evaluate environmental impacts throughout a building's life cycle. We utilize the Inventory of Carbon and Energy (ICE), one of the most reliable databases, for our assessment. Our findings indicate substantial differences when calculating embodied carbon for concrete as a singular material (first scenario) versus considering its component parts (second scenario). The first scenario results in at least a 20% increase in carbon emissions, with the exact discrepancy depending on the type of concrete materials and whether they are reinforced. Given that approximately 66% of the total quantity of our case study comprises concrete, these differences are substantial. Our study underscores the importance of incorporating embodied carbon factors into a unified database to accurately assess total embodied carbon emissions of buildings. It also highlights the potential for database uncertainty to skew interpretations of embodied carbon if an LCA is conducted for design reduction. Hence, a reliable baseline for calculating embodied carbon is crucial. Keywords: Life Cycle Assessment, Sustainability, Embodied Carbon, Concrete, Discrepanc

Life-cycle cost analysis of retrofit scenarios for a UK residential dwelling

The UK government is committed to reducing carbon dioxide emission levels by 80%, comparative to the 1990 baseline, by 2050. ‘Nearly-zero-energy buildings’ (nZEBs) were introduced by the Energy Performance Building Directive (recast) in 2010 as a realistic solution to the intrinsic environmental debt associated with most existing buildings. This paper aims to carry out a life cycle cost (LCC)analysis to identify what is a cost-optimal level and how best to achieve this by examining and focusing on the exploration of realistically applicable energy-efficient measures and retrofit scenarios for a typical UK dwelling. A sensitivity analysis is used to identify uncertainty and provide the expected economic benefits and losses of the applied scenarios over their respective lifetimes. It was established that the total LCCs of all the retrofit scenarios were in fact lower than that of the baseline scenario (i.e. not retrofitting the property) over the 30-year study period. Furthermore, it was found that the cost-optimal level for the retrofit of a typical UK residential dwelling is 75 (kWh/m2)/year; meanwhile, the UK’s current nZEB target stands at 44 (kWh/m2)/year, meaning that there is a gap between the current nZEB target and the calculated cost optimal level

Energy performance and cost analysis for the nZEB retrofit of a typical UK hotel

It is commonly known that commercial buildings contribute to a large proportion of energy consumption nationally and across Europe. The introduction of ‘nearly zero energy buildings’ (nZEBs) by the Energy Performance Building Directive [Recast] in 2010 has meant that a variety of active measures must be undertaken by the construction industry to define, shape, and meet the standard for both residential and commercial buildings. Hotels are typically ranked amongst the top five energy consumers in the tertiary sector. However, energy saving potential within the hotel industry is also significant. The aim of this study is to present an energy performance analysis and identify the primary energy consumption (PEC) level, post-retrofit, which could represent the cost-optimal level for a UK nZEB-hotel. Thermal Analysis Simulation software (Tas) is used to validate and assess the energy performance of the building pre- and post-retrofit. TasGenOpt is used to select individual EEMs that meet the nZEB targets and create the retrofit scenarios. Finally, building life cycle cost (BLCC) software is used to carry out the global cost calculations. It is found that whilst the nZEB target is technically feasible there is a 30 percent gap between the nZEB solution and the cost-optimal one. This is significant as it means that the current nZEB standard is not comparable to the best financial solution. The identified cost-optimal PEC level and recommendations provided may be used in the appraisal of other purpose-built UK nZEB hotel retrofits

Impact of cavity extraction fans on thermal and energy performance of existing UK hotel

The advantages of double-skin facade (DSF) systems, ranging between their aesthetic architectural benefits, acoustic benefits and ability to decrease the heating demand of the internal environment, have increased their popularity in Europe since the mid-1980s. However, appropriate consideration must be accorded to their design to ensure that their possible advantages are not negated. This work evaluates how the effect of extraction fans installed in the cavity of the DSF adjoining a central atrium impacts the thermal condition of the atrium and, consequently, the overall energy consumption of an existing UK hotel building. The results of the investigation demonstrated that the DSF extraction fans improve the internal temperature and condition of the adjacent central atrium, particularly in the summer. The fans result in a marginal increase in the overall energy consumption when operated throughout the year; hence, the optimum schedule for the operation of the extraction fans is during the cooling-dominant period