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Occupants account for a significant impact on building performance through their interactions with zone level building components. Empirically-derived occupant models, despite their potential to represent occupants’ impact in building performance simulation (BPS), have minimal penetration in design and code compliance processes. Instead, occupants are represented with static schedules or simple deterministic triggers. The objective of this paper is to better understand the influence of assumptions made in representing occupant interactions with building components over a BPS model's energy use and comfort predictions, as well as their ability to promote better design decisions. To this end, the energy and daylight performance of a generic perimeter office space in Ottawa, Canada were evaluated using a set of comprehensive performance metrics. Results indicate that representing dynamic occupant–building interactions lead to different energy predictions from the static schedules. The maximum difference in the total electricity use was for window-to-wall area ratios (WWR) of 20%, which was about 30% higher with the stochastic cases than the blind-open static cases. WWR 60% and 40% generally yielded the lowest lighting electricity use with the static and stochastic cases, respectively. This paper emphasizes the importance of incorporating empirically-derived dynamic occupant models for simulation-aided design and code compliance. [ABSTRACT FROM AUTHOR]

There are numerous strategies available to design and construct a low energy or nearly zero energy building (NZEB). However, the design strategy for a building depends on a high number of factors including location, climate, cost, available resources, etc. For instance, for countries like Ireland, which have a temperate oceanic climate, a key to achieving NZEB is a high thermal and air tightness performance of the building envelope, installing highly efficient space and water heating systems, and utilising renewable technologies for energy and heat generation. The challenge is to find the best combination of design strategies that would tackle the energy performance problems of a particular building. For example, is it better to design a super-insulated building with minimum heating requirements, or provide less insulation but install a large amount of renewable energy sources? This paper presents the outcomes of a number of case study buildings in Ireland, which focus on the life cycle cost and environmental analysis (using energy and global warming potential as indicators) of NZEBs using various heat sources, such as a gas boiler, biomass boiler, a domestic gas fired combined heat and power unit, heat pump and renewable technology. With the de-carbonisation and increased efficiency of the electricity grid, the low global warming potential (GWP) emissions of biomass fuels and the depletion of fossil fuels, future buildings should be (i) designed and constructed to be super-insulated with high air-tightness performance resulting in minimum heating requirements and (ii) operate with heating systems that have low impact on the natural environment, such as a biomass boiler or heat pump. [ABSTRACT FROM AUTHOR]

Evaluation methods can be used to determine what constitutes good energy performance in a building. With an increasing focus on energy use of buildings worldwide, this evaluation assumes a fundamental importance. This paper provides a comprehensive review of the available methods for analysing, classifying, benchmarking, rating and evaluating energy performance in non-domestic buildings. Methodologies are grouped in five categories: engineering calculations, simulation, statistical methods, machine learning and other methods. Techniques for evaluating buildings are described, their principal applications are shown and limitations are identified. The use of performance evaluation in energy efficiency programmes and standards is mapped. There is a need to further develop interactions between the main modelling techniques to produce simple, robust and validated models. Also, evaluation techniques must be developed to consider comfort or service provision in the buildings as a factor in energy performance. [ABSTRACT FROM AUTHOR]

Industrial halls pose high energy saving potential that is not yet explored under current design practice. Common design approaches such as parametric study or optimization are largely constrained by the assumptions and do not promote flexibility in the decision making process. Based on the unique characteristics of industrial halls, this paper develops a full factorial design space exploration approach to support multi-criteria design decision making. Energy performance, environmental impact, and cost effectiveness are studied over the whole life cycle. The approach is demonstrated with a case study of a warehouse in Amsterdam. Design parameters of interest are the insulation values, construction types, skylight coverage and transpired solar collector coverage. The results indicate that this approach offers design solutions that might not be otherwise identified. The non-case-specific one-time investigation allows objective space of derived performance to be generated dynamically based on even changing information or inputs specified by the users at the time of making the decision. This new design support approach facilitates designers to assess feasibility of any design solution based on their own desired set of performance requirement under different probable scenarios in the future. [ABSTRACT FROM AUTHOR]

Directives in the European Union are ensuring that buildings in this region are moving towards nearly zero energy buildings (NZEB). For countries like Ireland, which has a temperate oceanic climate, a key to achieving NZEB is to have high thermal and air tightness performances of the building envelope. Consequently, as the operational energy of the building reduces, the embodied energy (and embodied global warming potential) typically increases as a proportion of the lifecycle energy of the building due to increased embodied energy of the building envelope and the lower operational energy. In order to assess if a design strategy is in fact sustainable, it is becoming essential to evaluate environmental and economic LCA of building design strategies. This paper presents the outcomes of a number of case study buildings in Ireland, which focuses on the full environmental and economic lifecycle assessment of buildings to assess the impact changes in building regulations are having on the contribution of both the construction and operation of a building's lifecycle as they move towards NZEB standards. If designed with a focus on achieving a high thermal and air tightness, a building with an embodied energy intensity less than a building that achieves compliance with 2011 Irish building energy performance regulations can achieve a NZEB standard. [ABSTRACT FROM AUTHOR]

This paper provides a comparative study of the energy efficiency of a conventional ventilating and air conditioning (VAC) system with three configurations. This system was used to cool an experimental room in an office building in more control scenarios realised by adopting different cooled water temperatures and chiller cooling systems. In this purpose, an air–water mist cooled system for an air-cooled chiller is proposed. Depending on the components, the analysed VAC system has the following configurations: (1) air handling unit (AHU) and fan-coil units (FCUs); (2) air handling unit (AHU); and (3) heat recovery unit (HRU) and fan-coil units (FCUs). The electricity consumption weight of the equipment of each VAC system, the total energy consumption and the influence of control parameters on this consumption are analysed. The results of the experiments indicate that the optimal efficiency VAC system in office buildings includes an AHU and FCUs with an air–water mist cooled chiller and a cooled water temperature of 8 °C. For this system, a mathematical model is developed to minimise the electricity consumption by optimal control, where the consumption depends only on non-controlled parameters (solar radiation intensity and outdoor air temperature). This model is verified with actual measurements to confirm its accuracy, and a good agreement between the prediction and measurement is achieved. Additionally, the assessment of thermal comfort in the experimental office is performed based on the PMV-PPD model using the ASHRAE Thermal Comfort programme. The obtained results demonstrate that the AHU&FCUs system assures an increase in thermal comfort. Finally, a TRNSYS simulation model of energy consumption and PMV-PPD indices for the AHU&FCUs system is developed and experimentally validated. [ABSTRACT FROM AUTHOR]