Influence of insulating materials on green building rating system results

This paper analyzes the impact of a change in the thermal insulating material on both the energy and environmental performance of a building, evaluated through two different green building assessment methods: Leadership in Energy and Environmental Design (LEED) and Istituto per l'innovazione e Trasparenza degli Appalti e la Compatibilità Ambientale (ITACA). LEED is one of the most qualified rating systems at an international level; it assesses building sustainability thanks to a point-based system where credits are divided into six different categories. One of these is fully related to building materials. The ITACA procedure derives from the international evaluation system Sustainable Building Tool (SBTool), modified according to the Italian context. In the region of Umbria, ITACA certification is composed of 20 technical sheets, which are classified into five macro-areas. The analysis was developed on a residential building located in the central Italy. It was built taking into account the principles of sustainability as far as both structural and technical solutions are concerned. In order to evaluate the influence of thermal insulating material, different configurations of the envelope were considered, replacing the original material (glass wool) with a synthetic one (expanded polystyrene, EPS) and two natural materials (wood fiber and kenaf). The study aims to highlight how the materials characteristics can affect building energy and environmental performance and to point out the different approaches of the analyzed protocols

Engineering design applications of surrogate-assisted optimization techniques

The construction of models aimed at learning the behaviour of a system whose responses to inputs are expensive to measure is a branch of statistical science that has been around for a very long time. Geostatistics has pioneered a drive over the last half century towards a better understanding of the accuracy of such ‘surrogate’ models of the expensive function. Of particular interest to us here are some of the even more recent advances related to exploiting such formulations in an optimization context. While the classic goal of the modelling process has been to achieve a uniform prediction accuracy across the domain, an economical optimization process may aim to bias the distribution of the learning budget towards promising basins of attraction. This can only happen, of course, at the expense of the global exploration of the space and thus finding the best balance may be viewed as an optimization problem in itself. We examine here a selection of the state of-the-art solutions to this type of balancing exercise through the prism of several simple, illustrative problems, followed by two ‘real world’ applications: the design of a regional airliner wing and the multi-objective search for a low environmental impact hous

Building energy simulation and optimization of industrial halls

Industrial halls are characterized with their rectangular shape and relatively simple construction, as contrasted with office buildings with similar floor area. Industrial halls are usually subject to high energy demand due to the many manufacturing processes, lighting, and the corresponding amount spent on space conditioning. Thermal comfort is seldom a concern for industrial halls. By contrast, saving in energy consumption for lighting and space conditioning is a big issue since even the modest percentage change in energy consumption could be translated into a large monetary sum. With relatively loose requirement in space conditioning, and comparatively high internal heat gain; the approach in industrial hall design is quite different from that of office building. In fact, what poses to be an energy efficient design for office buildings might not be appropriate for high internal heat gain halls. The simplicity in the building geometry and the construction method allow the investigation of energy demand for space conditioning to be limited to a few number of demand side parameters (e.g. insulation value of walls); in which, change in values in some of the parameters presents a significant impact on the overall energy demand. This paper investigates the impact of varying different demand side parameters on the energy demand for space conditioning and lighting for a typical industrial hall. Through building energy simulation, such impact can be investigated; and by applying optimization, the configurations of the most optimal combinations of parameters with the lowest energy demand can be identified. The result indicates that the energy demand of the least efficient configuration can be more than double of that of the optimized design solution. This paper will also explore green building assessment systems such as LEED, in terms of energy performance, with the studied industrial hall as an example. The huge energy saving brought by the optimized design solution over the baseline building of LEED suggests that there might be a potential deficiency of LEED rating system at its current state as it applies to industrial halls

High-Performance Integrated Window and Façade Solutions for California

The researchers developed a new generation of high-performance façade systems and supporting design and management tools to support industry in meeting California’s greenhouse gas reduction targets, reduce energy consumption, and enable an adaptable response to minimize real-time demands on the electricity grid. The project resulted in five outcomes: (1) The research team developed an R-5, 1-inch thick, triplepane, insulating glass unit with a novel low-conductance aluminum frame. This technology can help significantly reduce residential cooling and heating loads, particularly during the evening. (2) The team developed a prototype of a windowintegrated local ventilation and energy recovery device that provides clean, dry fresh air through the façade with minimal energy requirements. (3) A daylight-redirecting louver system was prototyped to redirect sunlight 15–40 feet from the window. Simulations estimated that lighting energy use could be reduced by 35–54 percent without glare. (4) A control system incorporating physics-based equations and a mathematical solver was prototyped and field tested to demonstrate feasibility. Simulations estimated that total electricity costs could be reduced by 9-28 percent on sunny summer days through adaptive control of operable shading and daylighting components and the thermostat compared to state-of-the-art automatic façade controls in commercial building perimeter zones. (5) Supporting models and tools needed by industry for technology R&D and market transformation activities were validated. Attaining California’s clean energy goals require making a fundamental shift from today’s ad-hoc assemblages of static components to turnkey, intelligent, responsive, integrated building façade systems. These systems offered significant reductions in energy use, peak demand, and operating cost in California