Plasmonically Enhanced Reflectance of Heat Radiation from Low-Bandgap Semiconductor Microinclusions

Increased reflectance from the inclusion of highly scattering particles at low volume fractions in an insulating dielectric offers a promising way to reduce radiative thermal losses at high temperatures. Here, we investigate plasmonic resonance driven enhanced scattering from microinclusions of low-bandgap semiconductors (InP, Si, Ge, PbS, InAs and Te) in an insulating composite to tailor its infrared reflectance for minimizing thermal losses from radiative transfer. To this end, we compute the spectral properties of the microcomposites using Monte Carlo modeling and compare them with results from Fresnel equations. The role of particle size-dependent Mie scattering and absorption efficiencies, and, scattering anisotropy are studied to identify the optimal microinclusion size and material parameters for maximizing the reflectance of the thermal radiation. For composites with Si and Ge microinclusions we obtain reflectance efficiencies of 57 - 65% for the incident blackbody radiation from sources at temperatures in the range 400 - 1600 {\deg}C. Furthermore, we observe a broadbanding of the reflectance spectra from the plasmonic resonances due to charge carriers generated from defect states within the semiconductor bandgap. Our results thus open up the possibility of developing efficient high-temperature thermal insulators through use of the low-bandgap semiconductor microinclusions in insulating dielectrics.Comment: Main article (8 Figures and 2 Tables) + Supporting Information (8 Figures

Development of net zero energy settlements using advanced energy technologies

The research activities described in this paper focus on the development and implementation of a comprehensive and cost-effective system for Net Zero Energy (NZE) settlements. The system is composed of innovative solutions for the building envelope, for building energy generation, and for energy management at the settlement level. The developed solutions will be implemented in 4 different demonstration projects throughout the EU, with varying climates and building types. The results of their implementation will be monitored, analyzed. The target is to achieve a reduction of operational energy usage to 0-20 kWh/m2 per year through a transition from single NZE buildings to NZE settlements, in which the energy loads and resources are optimally managed. In addition, investment costs will be at least 16% lower than current nZEB costs. In this paper, the methodology that was developed in order to optimize the energy, environmental and cost plans of the four case studies through the best integration and combination of the selected innovative energy technologies with excellent architectural and engineering design is described. In addition the evaluation of the four NZE settlements in terms of energy, environmental and cost performance is presented

Bioclimatic Architecture and Urban Morphology. Studies on Intermediate Urban Open Spaces

This paper deals with the interactions between biophysical and microclimatic factors on the one hand with, on the other, the urban morphology of intermediate urban open spaces, the relationship between environmental and bioclimatic thermal comfort, and the implementation of innovative materials and the use of greenery, aimed at the users’ well-being. In particular, the thermal comfort of the open spaces of the consolidated fabrics of the city of Rome is studied, by carrying out simulations of cooling strategies relating to two scenarios applied to Piazza Bainsizza. The first scenario involves the use of cool materials for roofs, cladding surfaces, and pavement, while the second scenario, in addition to the cool materials employed in the first scenario, also includes the use of greenery and permeable green surfaces. The research was performed using summer and winter microclimatic simulations of the CFD (ENVI-met v. 3.1) type, in order to determine the dierent influences of the materials with cold colors, trees, and vegetated surfaces on the thermal comfort of the urban morphology itself. Meanwhile, the comfort assessment was determined through the physiological equivalent temperature (PET) calculated with the RayMan program. The first scenario, with the use of cool materials, improves summer conditions and reduces the urban heat island eect but does not eliminate thermal discomfort due to the lack of shaded surfaces and vegetation. The second scenario, where material renovations is matched with vegetation improvements, has a slightly bad eect on winter conditions but drastically ameliorates the summer situation, both for direct users and, thanks to the strong reduction of the urban heat island eect, to urban inhabitants as a whole

Environmental design solutions for existing concrete flat roofs in low-cost housing to improve passive cooling in western Mexico

The development of real estate in Mexico has largely ruled out the comfort of users that focused on economic matters and made it difficult to make substantial progress in adopting measures to improve indoor environmental quality. Current research projects in Mexico found that roof construction in low-cost housing struggles to meet the requirements of the indoor climate. Passive cooling strategies are techniques to control heat gain and heat dissipation in buildings to maximise the comfort and health of building users while minimising energy use. Passive cooling systems recognize climate conditions and utilise renewable sources of energy such as the sun and wind to provide cooling and ventilation. Therefore, this study aims to develop a green and sustainable solution for existing concrete flat roofs with no major interventions and investments to save energy. The design of a passive device was tested to assess its effectiveness to protect flat roofs from shortwave radiation and to allow for heat dissipation in Mexican buildings. The study used a quantitative approach based on experiments and simulation tests to evaluate design efficiency. The results showed that a perforated device with an opening percentage of 88% and a cavity of 0.05m between the roof and the device provided effective protection. Also, the device with blinds of 45° showed lower operative temperatures within a range of mean values between 0.8°C and 0.9°C compared to a roof with a full shade cover in the hot and humid season. However, the perforated device with blinds of 90° in black colour delivered the best performance compared to other models and recorded a mean value of 1.13°C in the hot sub-humid season. The results revealed the efficiency of the proposed device that can be observed within different geometric configurations, surface properties as well as the use of the nocturnal radiative cooling potential in blocking solar radiation in Mexican buildings

From the Sum of Near-Zero Energy Buildings to the Whole of a Near-Zero Energy Housing Settlement: The Role of Communal Spaces in Performance-Driven Design

Almost a century ago Modernism challenged the structure of the city and reshaped its physical space in order to, amongst other things, accommodate new transportation infrastructure and road networks proclaiming the,nowadays much-debated ‘scientificated’ pursuit of efficiency for the city. This transformation has had a great impact on the way humans still design, move in, occupy and experience the city. Today major cities in Europe, such as Paris and London, are considering banning vehicles from their historic centers. In parallel, significant effort is currently underway internationally by designers, architects, and engineers to integrate innovative technologies and sophisticated solutions for energy production, management, and storage, as well as for efficient energy consumption, into the architecture of buildings. In general, this effort seeks for new technologies and design methods (e.g., DesignBuilder with EnergyPlus simulation engine; Rhicoceros3D with Grasshopper plugin and Ecotect, Radiance and EnergyPlus tools) that would enable a holistic approach to the spatial design of Near-Zero Energy buildings, so that their ecological benefits are an added value to the architectural design and a building’s visual, and material, impact on its surrounding space. The paper inquires how the integration of such technological infrastructure and performance-orientated interfaces changes yet again the structure and form of cities, and to what extent it safeguards social rights and enables equal access to common resources. Drawing from preliminary results and initial considerations of ongoing research that involve the construction of four innovative NZE settlements across Europe, in the context of the EU-funded ZERO-PLUS project, this paper discusses the integration of novel infrastructure in communal spaces of these settlements. In doing so, it contributes to the debate about smart communities and their role in the sustainable management of housing developments and settlements that are designed and developed with the concept of smart territories