Procedia environmental sciences最新文献

Based on a comparative case study of Malmö Bo01 (Sweden), Barcelona Trinitat Nova (Spain), Bordeaux Ginko (France), and Docks de Saint Ouen (France), this paper shows that there are substantial differences in the practical interpretation of the term eco-district, and that the eco-district framework has evolved to suit different governmental systems and cultures. The four urban development projects arrive at similar outcomes and a common understanding of “urban sustainability”, yet their structures differ. Cities and city governments go above and beyond the national and international guidelines and tailor policies to meet their local priorities.

Sustainable transportation – or green transportation – is an important field in terms of generating a healthy environment and upgrading city planning. Street design and modes of transportation are the two main factors that can affect the sustainability of city planning. This paper focuses on designing and planning an efficient, sustainable street using affordable and common modes of transportation, with an emphasis on two cities in Egypt and Lebanon as case studies.

Observing developing cities in the field of transportation planning reveals many weaknesses that have a major effect on citizens, such as traffic congestion, a shortage of pedestrian walkways or cycling paths, a lack of affordable public transportation or its sequential movement, and the new modes of informal transportation that have appeared in recent years and have affected the street transportation movement.

The aim of this paper is to analyse developing cities in terms of modes of transportation, to discover an effective method of planning city streets.

Throughout the history, the city of Jeddah acted as a main gate to the Holy cities, starting specifically in the era of the third Muslim Caliph Othman Bin Affan in 647 AC, when he ordered the city to be a port to welcome pilgrims coming for the Holy Pilgrimage. Since then and till now the city plays an important role as a main gateway. Regarding this importance many plans, initiatives and researches are being developed to enhance the city role to cope with potential challenges and requirements, especially focusing on renovating the city center and its connection with the city gates. Insights into gateways sustainable developments, demonstrates that Jeddah city incentives smart growth approach in terms of its important geographical location, heritage importance as well as connectivity to the Holy cities. This highlights the importance of elaborate urban management processes in terms of city future expansions, public activities as well as major functions including economic and business, knowledge, transport. A study of main urban solutions to support policy decisions strengthening sustainable smart growth of the Jeddah city. The methodology adopted in the research is focusing on presenting expected improvements on Jeddah master plan as well as adopted strategies in order to improve the livability and quality of life in a community public activities. Explicit Contextual proposal is demonstrated to stimulate the regeneration of Jeddah gate arising from the city core center area towards city's existing boundaries while diversifying activities and supporting economic growth, highlighting road networking and accessibility as well as transport infrastructures. The research presents sustainable scenario to maximize Jeddah Gateway potentials related to economic, cultural importance, in addition to maintaining its heritage and touristic approach.

The current paper describes an innovative high efficiency closed loop ground coupled heat exchanger (GCHE), which is already protected by a Greek patent, while protection at European level is pending.

Closed loop GCHEs are used in shallow geothermal energy systems, which are a relatively widespread renewable energy sources (RES) technology. The exploitation of shallow geothermal energy is achieved through energy systems which provide heating/cooling and/or domestic hot water in several types of buildings (houses, offices, hotel complexes, schools, shopping centers, etc.) and in other applications (such as swimming pools, greenhouses, ice melting, etc.). It is noteworthy that the above mentioned energy systems are widely known as ground source heat pumps (GSHPs) or simply shallow geothermal energy systems. It should be emphasized that GCHEs are one of the main parts of a closed loop GSHP system. The installation of closed loop GCHEs is achieved, mainly, through two geometrical patterns: horizontal and vertical.

The innovative high efficiency closed loop GCHE is going to be used for the exploitation of the internal thermal energy (U) of the medium (ground or aquatic environment) with which it comes into contact. In particular, this innovative high efficiency closed loop GCHEconsists of plastic piping which has been mounted to a specific metallic mechanism. Furthermore, the innovative high efficiency closed loop GCHEhas several advantages in relation to a conventional closed loop GCHE, such as: a) higher degree of exploitation of the internal thermal energy (U) of the medium, b) decrease of the manufacturing and installation costs, c) decrease of the length (m) of the borehole drilling in vertical systems and d) decrease of the required application area (m²) in horizontal systems.

In conclusion it is expected that the use, production and commercialization of the innovative high efficiency closed loop GCHEsmay facilitate further diffusion of GSHPs contributing, among others, to the reduction of CO₂ and other gas emissions, to environmental protection, to energy savings and to the creation of new jobs —a glimmer of hope against the economic recession of Greece.

Vegetation affects the urban space microclimate in many ways, almost all of them being highly beneficial. At the level of city block, street or individual building, cooling from evapotranspiration is one of the most significant effects of vegetation with an impact on urban microclimate. However, this effect is difficult to be quantified in energy simulations. A tool that would contribute to the integration of fully parameterized vegetation effects into environmental analysis software for buildings and urban spaces would be of great usefulness. To this end, this work proposes a methodology that attempts to quantify evapotranspiration from single trees and vegetation ground cover. Of great importance is the simplicity in its implementation, as well as the minimum and easily obtained user input requirements.

This methodology is primarily based on the Pennman-Monteith evapotranspiration equation, as modified by the Food and Agriculture Organization of the UN. By a combination of collecting data for vegetation parameters from literature and incorporating equations for estimating some of the physical tree properties necessary as input to this method, a tool is assembled. Several tree species were categorized and included as options when calculating the cooling effect of vegetation in a system, based on this research. Evapotranspiration is then calculated depending on the specific tree species selected and the environmental data entered. The inclusion of the results in CFD environmental analysis is demonstrated.

Variations in the calculation method are applied, depending on the desired time-step of the simulation. Thus, the tool can be used either in static or dynamic form, according to the available data and required accuracy. A web version of the tool in its static instance has been created, as a form-based webpage. An executable version will provide hourly calculations of evapotranspiration by importing weather data files and dynamically altering the equations according to the environmental variables, plotting the results in graphs.

Following development and validation of the Solene-microclimat tool, the model was used to compare the impacts of various “greening strategies” on buildings’ summer energy consumption and indoor comfort. The studied strategies were greening walls, roofs, and ground (lawns). Solene-microclimat enables to simulate simultaneously a building's thermal behavior and the microclimate at the district scale, with the retroaction of buildings on climate. Distinguishing between direct (due to the modification of building’ characteristics) and indirect impacts (due to the modification of boundary conditions) of these surfaces is also possible. Thus, the strategies were successively implemented on the studied building, the surroundings, and both of them. The simulations were carried out using Solene-microclimat considering insulated vs. non-insulated buildings. Findings confirm that the direct and indirect effects of theses surfaces are almost negligible on insulted buildings. For non-insulated ones, green walls have a direct effect on indoor comfort throughout the entire building, whereas the effect of green roofs is primarily confined to the upper floor. Moreover, the indirect effect of a green wall is greater, mainly due to the drop in infrared emissions resulting from a lower surface temperature. It has also been proven that the indirect effects of green walls and surrounding lawns can help reduce the loads acting on a non-insulated building. Direct and indirect effect can’t be directly added. This is particularly interesting for heritage buildings or highly glazed ones the refurbishment of which is often difficult.

Hotel buildings are unique compared to other public, commercial buildings due to their varying size as well as their facilities and operating schedules. Recent studies indicate that hotels are the second highest energy consuming category after hospitals. Even though they represent only 0.82% of the building stock, they reflect 28% of the total final energy use in the tertiary building sector of Greece. The reported average energy consumption for Greek hotels is 273kWh/m² annually. Purpose of this Master Thesis was to evaluate different energy optimization scenarios for an existing hotel building as a case study and calculate the potential energy savings using the Greek software TEE-KENAK. Three main subjects were investigated: the building envelope, the electromechanical systems and the application of renewable energy technologies. Based on the results from several simulations, it is concluded that it is possible to reach an average reduction of 60% in the annual primary energy consumption.

Nowadays, over half of the world's population is living in urban areas. Urbanization has not led only to economic and social transformation, but also to high resource consumption and considerable environmental damage. This study aims to promote a holistic methodological approach in the urban context in order to foster policy modeling, efficient governance and sustainability. The paper has a twofold purpose: (i) to provide an approach for tractably characterizing the environmental performance of the building sector, and (ii) to promote sustainable practices towards greener buildings in urban areas. Towards this aim a composite indicator is analytically defined. The index combines the main environmental pressures that can be attributed to the building sector and is mathematically formulated to be finally implemented generically. Apart from energy, water consumption and waste generation, the presented scheme establishes links with LCA in order to include estimations of carbon footprint (CO₂-eq). The formulated index is combined with the structure dialogue approach that has been developed within Urban Empathy, aMED Programme funded capitalization project focused on the efficiency of sustainable urban policies in the Mediterranean Basin. The structured dialogue process identifies key barriers to the implementation of the selected available practices into sustainable urban policies for the building sector. The paper highlights insights for common priorities, real pilot project results and their relation to implemented policies in order to foster strategic governance and policy modeling for specific areas under consideration.